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R-05-12-01-9C1 - 12/1/2005RESOLUTION NO. R -05-12-01-9C1 WHEREAS, the City of Round Rock ("City") is undertaking the construction of approximately 4,160 linear feet of Dry Branch tributary channel improvements to correct problems of bed scour and bank stability, as well as to address concerns of public safety associated with flooding; and WHEREAS, Continental Homes of. Texas, L.P. d/b/a D.R. Horton ("Developer") is also constructing channel modifications on approximately 2,380 linear feet of the same channel for a total of 6,540 linear feet of improvements for the Dry Branch Project ("Project") ; and WHEREAS, this Project will impact 2.24 acres of waters of the United States and, as a result, the City has undertaken to secure a Section 404 permit ("Permit") from the Corps of Engineers having jurisdiction over the Project; and WHEREAS, the City is the only applicant for the Permit and therefore the.City needs to ensure that all work performed on the .Project .is completed timely and under the terms and conditions set forth in the Permit; and WHEREAS..; the Developer desires to enter into a Development Agreement to..assure that the .Project is constructed in a timely manner and in accordance with the terms and conditions set forth in the Permit, Now Therefore BE IT RESOLVED BY THE COUNCIL OF THE CITY OF ROUND ROCK, TEXAS, That the Mayor ishereby authorized and directed to execute on behalf of the City a Development Agreement with Continental Homes of @PFDesktop\::ODMP_/WORLDOX/O:/WDOX/RESOLUTI/R.51201C1.WPD/bbw Texas, L.P., a copy of same being attached hereto as. Exhibit "A" and incorporated herein for all purposes. The City Council hereby finds and declares that written notice of the date, hour, place and subject of the meeting at which this Resolution was adopted was posted and that such meeting was open to the public as required .by law at all times during which this Resolution and the subject matter hereof were discussed, considered and formally acted upon, all as required by the Open Meetings Act, Chapter 551, Texas Government Code, as amended. - RESOLVED this 1St day of December, 2005. ST: WE , Mayor Ci y of Round Rock, Texas CHRISTINE R. MARTINEZ, City Sec'-tary 2 DEVELOPMENT AGREEMENT This DEVELOPMENT AGREEMENT ("the Agreement") is made and entered into on this the day of the month of , 2005, by and between the CITY OF ROUND ROCK, TEXAS, a home rule municipal corporation ("City"), and CONTINENTAL HOMES OF TEXAS, L.P., a Texas limited partnership, ("Continental"), and its successors and assigns. RECITALS: WHEREAS, the parties desire to construct channel modifications for Dry Branch tributary to correct problems of bed scour and bank stability, as well as to address concerns of public safety associated with flooding ("Dry Branch Project") as shown on Exhibit A attached hereto and made a part hereof by reference for all appropriate purposes; and WHEREAS, the Dry Branch Project will impact 2.24 acres of waters of the United States both permanently and temporarily and as a result the City has undertaken to secure a permit ("404 Permit") from the Corps of Engineers having jurisdiction over the Dry Branch Project as set forth in Exhibit B attached hereto and made a part hereof by reference for all appropriate purposes; and WHEREAS, the 404 Permit requires the City to comply with the terms of the General and Special Conditions contained within the 404 Permit and the Texas Commission on Environmental Quality Section 401 Water Quality Certification, dated August 5, 2005 (TCEQ Certification") ; and WHEREAS, the City, as a condition to allowing any work to be performed on the Dry Branch Project, must require compliance with the General and Special Conditions and the TCEQ Certification contained in the 404 Permit by all parties, their contractors and subcontractors performing the permitted activities for the Dry Branch Project; and WHEREAS, City and Continental desire to enter into this Agreement to set forth in writing certain covenants and conditions, and to set forth their whole agreement; NOW, THEREFORE, for and in consideration of the mutual covenants contained herein and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, City and Continental agree as follows: AGREEMENT 1. Dry Branch Project. The Dry Branch Project will consist of the following: (a) widening of 4,000 linear feet of natural stream channel; 00092401/bbw (b) construction of a low flow channel and adjacent floodplain bench in 2,540 linear feet of previously channelized stream channel; and EXHIBIT b a "A" (c) implementation of a mitigation plan concurrently with construction and operation of the Dry Branch Project to offset adverse impacts to the waters of the United States such Mitigation Plan ("Mitigation Plan") being attached hereto as Exhibit C and made a part hereof by reference for all appropriate purposes. 2. Effective Date. This Agreement shall be effective on the date it has been signed by the City of Round Rock. 3. Construction and Completion of Dry Branch Project. Continental and the City agree to be responsible for all costs of development and construction for their respective portions of the Dry Branch Project shown on Exhibit attached hereto and made a part hereof by reference for all appropriate purposes. The parties agree that all construction shall be done in full conformance with the terms and conditions set forth in the 404 Permit and the Mitigation Plan, as well as all other laws or regulations. Continental agrees to secure and pay for all necessary additional permits and licenses required for its performance of the Dry Branch Project. The parties agree that construction of the Dry Branch Project will timely commence and be completed, and will be accepted by City, by December 31, 2007. Subject to the warranty set forth below and Mitigation Plan requirements, once the referenced construction has been accepted by City, City agrees to thereafter maintain the improvements and release Continental from any on- going maintenance responsibility regarding the channel. 4. Warranty. Following completion and acceptance, Continental agrees to provide a three (3) year warranty to City coextensive with that required under the terms of the 404 Permit. Said warranty will provide that all Mitigation Plan activities, including tree and other vegetation plantings of whatever kind or nature and the planting success criteria will comply with the terms of both the 404 Permit and the City's ordinances. 5. Bond. Continental understands and agrees to secure a performance bond, the form of which is attached hereto as Exhibit E and made a part hereof by reference for all appropriate purposes, in the amount of Eight Hundred Thousand Dollars ($800,000.00) as part of this Agreement. Such performance bond shall have a term of one year following completion of the Dry Branch Project by Continental and acceptance by the City. 6. Stipulations by Parties. The parties agree, and Continental explicitly stipulates, that as part of the Mitigation Plan, approximately 3.26 acres of Continental property, as shown more fully on Exhibit F, attached hereto and made a part hereof by reference for all appropriate purposes, shall be utilized solely for additional riparian tree plantings. Continental further stipulates that it will enter into a Conservation Easement with the City whereby Continental's portion of approximately 8.361 acres along Lake Creek, approximately 1/4 mile north of the Dry Branch tributary, as shown more fully on Exhibit G, attached hereto and made a part hereof by reference for all appropriate purposes, shall become a high-quality Riparian Preservation Zone which will thereafter remain under the City's control in perpetuity. Continental stipulates and agrees to provide any information that may be necessary for any ongoing reports that may be required under the terms of the 404 Permit, the Mitigation Plan or the TCEQ Certification. 2 7. No Partnership. This Agreement will not be construed in any form or manner to establish a partnership, joint venture or agency, express or implied, nor any employer-employee or borrowed servant relationship by and among the parties. 8. Notice. All notices and other communications in connection with this Agreement shall be in writing and shall be considered given as follows: (i) when delivered personally to the recipient's address as stated in this Agreement; or (ii) when sent, by certified or registered mail, return receipt requested, to the recipient's address as stated in this Agreement. The addresses of the parties provided below may be changed by similar notice in writing given by the party whose address is to be changed. For the purposes of this Section 8, the addresses of the parties for all notices are as follows: If to City: With a copy to: If to Continental: With a copy to: 9. Miscellaneous. City of Round Rock, Texas Attention: James R. Nuse, P.E., City Manager 221 East Main Street Round Rock, TX 78664 Stephan L. Sheets, City Attorney Sheets & Crossfield, P.C. 309 East Main Street Round Rock, TX 78664 Continental Homes of Texas, L.P. Attention: Richard N. Maier 12554 Riata Vista Circle, Second Floor Austin, Texas 78727 (a) Force Majeure. Neither City nor Continental shall be deemed in violation of this Agreement if it is prevented from performing any of its obligations hereunder by reasons for which it is not responsible or circumstances beyond its control. However, notice of such impediment or delay in performance must be timely given and all reasonable efforts undertaken to mitigate its effects. (b) Assignment. This Agreement may not be assigned without the prior express written consent of the other party, which consent shall not be unreasonably, withheld, conditioned or delayed. 3 (c) Modification This Agreement may not be modified or amended except by a subsequent agreement in writing signed by both parties. (d) Binding Effect. This Agreement will be binding upon and inure to the benefit of the parties hereto and their respective successors, legal representatives and assigns. (e) Entire Agreement. This Agreement and all exhibits attached hereto, plus any referenced site plans and construction plans, constitute the entire agreement and understanding between the parties and supersede all prior and contemporaneous agreements and understandings of the parties in connection therewith. (f) Governing Law. This Agreement will be construed and interpreted in accordance with the laws of the State of Texas and venue for any legal proceedings instituted regarding this Agreement will be in Williamson County, Texas. (g) Captions. The captions in this Agreement are inserted for convenience of reference only and in no way define, describe or limit the scope or intent of this Agreement or any provisions hereof. (h) Gender and Number. Words of any gender used in this Agreement will be construed to include the other gender and words in the singular number will be construed to include the plural, and vice versa, as the context may require herein. (i) Multiple Counterparts. This Agreement may be executed in a number of identical counterparts which, taken together, shall constitute collectively one (1) agreement; but in making proof of this Agreement, it shall not be necessary to produce or account for more than one such counterpart. - Signature Block on the following page - 4 EXECUTED on this the day of , 2005. ATTEST: CITY OF ROUND ROCK, TEXAS Christine R. Martinez, City Secretary APPROVED AS TO FORM: Stephan L. Sheets, City Attorney By: Printed Name: Nyle Maxwell Title: Mayor Date: CONTINENTAL HOMES OF TEXAS, L.P., a Texas limited partnership By: CHTEX of Texas, Inc., a Delaware corporation, its sole general partner 5 By: Richard N. Maier Title: Vice -President Date: EXHIBIT A Dry Branch Project Base Map Source: USGS 7.5 Min. Topographical quadrangle of Round Rods (1987) & PIlugerville West (1987) APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SCALE: 1" = 2000' N DRY BRANCH TRIBUTARY CHANNEL IMPROVEMENTS PROJECT LOCATION SHEET 1 OF 20 EXHIBIT B Department of Army Permit DEPARTMENT OF THE ARMY PERMIT Permittee City of Round Rock, Texas - Permit No. 200200684 Issuing Office Fort Worth District NOTE: The term "you" and its derivatives, as used in this permit, means the permittee or any future transferee. The term "this office" refers to the appropriate district or division office of the Corps of Engineers having jurisdiction over the permitted activity or the appropriate official of that office -acting under the authority of the commanding officer. Project Description: Discharge of approximately 5,100 cubic yards of dredged and fill material into 2.24 acres of waters of the United States (6,540 linear feet of perennial stream) associated with the construction of a channelization and stabilization project. Elements of the project include: widening 4,000 linear feet of natural stream channel; construction of a low flow channel and adjacent floodplain bench in 2,540 linear feet of previously channelized stream channel; and implementation of a mitigation plan concurrently with construction and operation of the project to offset adverse impacts to waters of the United States. Project Location: The proposed channelization and stabilization project would be located on a tributary to Dry Branch Creek downstream of Caddis School Road in the city of Round Rock, Williamson County, Texas. The proposed project would be located approximately at UTM coordinates 628923.248 East and 3375443.635 North (Zone 14) on the Round Rock 7.5 -minute USGS quadrangle map in the USGS Hydrologic Unit 12030102. Permit Conditions: In accordance with attached Sheets 1-20 of 20 and Texas Commission on Environmental Quality Section 401 Water Quality Certification, Pages 1-2 of 2, dated August 5, 2005. General Conditions: 1. The time limit for completing the work authorized ends on December 31, 2010 . If you find that you need more time to complete the authorized activity, submit your request for a time extension to this office for consideration at least one month before the date is reached. 2. You must maintain the activity authorized by this permit in good condition and in conformance with the terms and conditions of this permit. You are not relieved of this requirement if you abandon the permitted activity, although you may make a good faith transfer to a third party in compliance with General Condition 4 below. Should you wish to cease to maintain the authorized activity or should you desire to abandon it without a good faith transfer, you must obtain a modification of this permit from this office, which may require restoration of the area. 3. If you discover any previously unknown historic or archaeological remains while accomplishing the activity authorized by this permit, you must immediately notify this office of what you have found. We will initiate the Federal and state coordination required to determine if the remains warrant a recovery effort or if the site is eligible for listing in the National Register of Historic Places. 4. If you sell the property associated with this permit, you must obtain the signature of the new owner in the space provided and forward a copy of the permit to this office to validate the transfer of this authorization. 5. If a conditioned water quality certification has been issued for your project, you must comply with the conditions specified in the certification as special conditions to this permit. For your convenience, a copy of the certification is attached if it contains such conditions. ENG FORM 1721, Nov 86 EDITION OF SEP 82 IS OBSOLETE. (33 CFR 325 Appendix A)) 6. You must allow representatives from this office to inspect the authorized activity at any time deemed necessary to ensure that it is being or hasbeen accomplished in accordance with the -terms and conditions of your permit. Special Conditions: SEE PAGE 4 (Special Conditions) Further Information: 1,- Congressional Authorities: You have been authorized to undertake the activity described above pursuant to: O Section 10 of the Rivers and Harbors Act of 1899 (33 U.S.C. 403). Section 404 of the Clean Water Act of 1972 (33 U.S.C. 1344). Section 103 of the Marine Protection, Research and Sanctuaries Act of 1972 (33 U.S.C. 1413). 2. Limits of this authorization. a. This permit does not obviate the need to obtain other Federal, state, or local authorizations required by law. b. This permit does not grant any property rights or exclusive privileges. c. This permit does not authorize any injury to the property or rights of others. d. This permit does not authorize interference with any existing or proposed Federal project. 3. Limits of Federal Liability. In issuing this permit, the Federal Government does not assume any liability for the following: ( a. Damages to the permitted project or uses thereof as a result of other permitted or unpermitted activities or from natural causes. b. Damages to the permitted project or uses thereof as a result of current or future activities undertaken by or on behalf of the United States in the public interest. c. Damages to persons, property, or to other permitted or unpermitted activities or structures caused by the activity authorized by this permit. d. Design or construction: deficiencies associated with the permitted work. e. Damage claims associated with any future modification, suspension, or revocation of this permit. 4. Reliance on Applicant's Data: The determination of this office that issuance of this permit is not contrary to the public interest was made in reliance on the information you provided. 5. Reevaluation of Permit Decision. This office may reevaluate its decision on this permit at any time the circumstances warrant. Circumstances that could require a reevaluation include, but are not limited to, the following: a. You fail to comply with the terms and conditions of this permit. b. The information provided by you in support of your permit application proves to have been false, incomplete, or inaccurate (See 4 above). c. Significant new information surfaces which this office did not consider in reaching the original public interest decision. 2 Such a reevaluation may result in a determination that it is appropriate to use the suspension, modification, and revocation procedures contained in 33 CFR 325.7 or enforcement procedures such as those contained in 33 CFR 326.4 and 326.5. The referenced enforcement procedures provide for the issuance of an administrative order requiring you to comply with the terms and conditions of your permit and for the initiation of action where appropriate. You will be required to pay forany corrective measures ordered by this office, and if you fail to comply with such directive, this office may in certain situations (such as those specified in 33 CFR 209.170) accomplish the corrective measures by contract or otherwise and - -bill-you for the cost. 6. Extensions. General condition 1 establishes a time limit for the completion of the activity authorized by this permit. Unless there are circumstances requiring either a prompt completion of the authorized activity or a reevaluation of the public interest decision, the Corps will normally give favorable consideration to a request for an extension of this time limit. "Your:signature below, as permittee, indicates that you accept and agree to comply with the terms and conditions of this permit. (PERMITTEE) Mr. Michael Thane City of Round Rock, Texas (DATE) This permit becomes effective when the Federal official, designated to act for the Secretary of the Army, has signed below. (FOR THE) (DISTRICT ENGINEER) John R. Minahan Colonel, Corps of Engineers (DATE) When the structures or work authorized by this permit are still in existence at the time the property is transferred, the terms and conditions of this permit will continue to be binding on the new owner(s) of the property. To validate the transfer of this permit and the associated liabilities associated with compliance with its terms and conditions, have the transferee - sign and date below. (TRANSFEREE) (DATE) 3 Special Conditions - Permit Number 200200684 1. The permittee shall implement and abide by the mitigation plan titled "Project Mitigation Plan for Dry Branch Tributary' by Hicks and Company, dated April 2005. The permittee shall implement the mitigation plan concurrently with the construction of the project and complete the initial construction and plantings associated with the mitigation work prior to completion of construction of the project. Completion of all elements of this mitigation plan is a requirement of this permit. 2.. The permittee shall be responsible for maintaining the mitigation areas enhanced and created to comply with Special Condition 1 above until such time as the permittee provides documentation to, and receives verification from, the Regulatory'Branch, Fort Worth District, U. S. Army Corps of Engineers (USACE), that areas within the mitigation area intended to become: a. waters of the United States meet the definition of a waters of the United States under the Regulatory Program regulations applicable on the date of this permit; b. waters of the United States are functioning as the intended type of waters of the United States and at an acceptable level of ecological performance; and c. buffer and riparian zones and other areas integral to the enhancement of the aquatic ecosystem are functioning as the intended type of ecosystem component and at an acceptable level of ecological performance. 3. The permittee shall dedicate in perpetuity by deed restriction, as a stream mitigation area, the approximately 8.25 acre mitigation area identified in the mitigation referenced in special condition 1 above. The only exceptions to the deed restriction shall be easements in existence on the date of this permit: The mitigation area shall not be disturbed, except by those activities that would not adversely affect the intended extent, condition, and function of the mitigation area._ The permittee shall survey the mitigation area,develop an_ appropriate_deedrestriction for the surveyed area, submit the draft deed restriction to the USACE for review and approval, and record the USACE approved deed restriction with the County Clerk. The permittee shall provide a copy of the recorded deed restriction to the USACE by November 1, 2005. The restriction shall not be removed from the deed or modified without written approval of the USACE and conveyance of any interest in the property must be subject to the deed restriction. 4. The permittee may mow the floodplain benches within the trapezoidalchannel and the adjacent 3.25 -acre riparian preservation zone, but shall limit any such mowings to: a minimum height of 10 inches, a maximum of twice per year, and during the winter dormant season from December through February. 5. The permittee shall conduct a meeting with the construction contractor(s). detailing the terms and conditions of this permit prior to commencing construction activities of the project. The permittee shall notify the USACE of the preconstruction contractor meeting at least two weeks in advance of the meeting. Within two weeks following the meeting, the permittee shall provide written confirmation to the USAGE that the meeting was held. 6. The permittee shall retain a qualified mitigation specialist (biologist, ecologist or other specialist qualified in wetland restoration, enhancement, and creation work), to oversee project construction to the extent necessary to ensure compliance with all mitigation requirements of this permit The permittee shall have this mitigation specialist conduct all monitoring and produce any required monitoring reports. 7. The permittee shall establish and implement a self-monitoring program that includes the following actions: a. designation, in writing, of a responsible party to coordinate with the USACE concerning on-site inspections and compliance with permit conditions; b. notification to the USACE of the schedule of activities for each phase of the project at least 30 days prior to the start of soil -disturbing activities that would affect waters of the United States; and 4 c. implementation of a reporting program that shall include annual written compliance reports to the USACE, due October 1 for annual reporting each year, beginning in October 1, 20.05. The permittee shall include in each report any schedule changes and a summary of all activities that occurred during the reporting period, including documentation_ of the permittee's compliance with the permit_ conditions and progress and/or completionofall authorized work, including mitigation activities. Each report shall address whether disturbed areas, such as borrow ditches, road embankments, stream banks, road crossings, and temporary impact areas are revegetating adequately and not suffering erosion damage. The permittee shall detail in the first report the pre -construction conditions of the project area. The permittee shall include in each report photographs, maps, and a description of the impacts to waters of the United States. Compliance reports are required even if no work is conducted during the reporting period. The permittee shall submit compliance reports until the USACE verifies that the permittee has successfully completed all compensatory mitigation plan requirements, the mitigation areas have met the standards of special condition- 1, and all authorized construction activities have been either completed or deleted from the project. 5 Base Map Source: USGS 75 Min. Topographical Quadrangle of Round Rock (1987) 8 PtlugeMNe Weal (1987) APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SCALE: 1' = 2000' N DRY BRANCH TRIBUTARY CHANNEL IMPROVEMENTS PROJECT LOCATION SHEET 1 OF 20 Base Map Source: USGS 7.5 Min. Topographical Quadrangle of Round Rock, TX (1987) & Pflugerville West, TX (1987) NI i' Scale: 1" = 2000' PREVIOUSLY cHANE)L1EQAREA . .. �t AREA NOT PREVIOUSLyHAt 1 -4.04#E0 - APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 2 OF 20 APPLICANT CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 3 OF 20 0 0 o Qa 100HOS S111vO 00 C0 0 0 0 N 1 H W c W > O d CY_ 2I - m J LL (1) ,W 2 LZo U m U•ct w. X t�z W Z ri < o-: a. 0u? Qoo ce w0 > Z 0 0 LL 00 U M TO SHE rm APPLICANT: . 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APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 12 OF 20 PROPOSED• TURTLE CREEK VILLAGE PUD,: t South Creek. ( EXISTING ) EXISTING (FEMA) 10 YEAR FLOODPLAIN PRQPQ$ED tia:�• MODIFIED 1QOYEAR FLOODPLAIN Greenslopes at Lake Creek (EXISTING ) Propo-sdd Turtle Creek Village PUD Source: Gray JansIng & Associates, 2001. APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 20206684 DATE: FEBRUARY 2005 SHEET 13 OF 20 pEtERAL NOTES: ' 1. USE ONLY OPEN GRADED ROCK 3- IH DIAMETER. 2. THE. BERM SHALL ..6EWIRE OF WOVEN WIRE TING Ifs► • 1 RICH • AND { A WIR II IRAI :.. 20 CAS. • 3. :r114*ROCK Roof -VI -Am DE Mete' WE KLY OR AFTER aptRMN. AND THE STORE MOM C DOE WOYEH. WIRE: tEATIIIHO SHALL.BE REPLACED' WHEN I STRUCTURE:CEASES TO FUNCTION AS RfJEt1DED. DUE TO. Sits' ACCUMULATION Motto G THE .RCCES. WASHOUT. tAIIS1RUCi10M IRAFFIR DAMA# ETC. �. WHEN - SSIT REACHES : A DEPTH EQUAL TO ONE—THIRD THE HE1 8T .OF' THE D(RM RR 0!f• FOOT. WHICHEVER iS LESS. TIE SILT SHALL DE R I4OVED MW DISPDSED OF III. AIi AnRO IED SITE AND RI SUCH A WRIER AS TO' NOT CREATE A SLTAT)ON PROBLEM. 5. DAILY INSPECTION SHALL BE 1NADE ON SEVERE SERVICE ROCK BERMS; SILT SHALL BE REMOVED WHEN ACCUMULATION REACHES 6 :NICHES. 6. WHEN THE SITE IS mummy SiASIUZED. THE BERM ANO SATED SILT SNAIL ERE REMOVED AI4D DISPOSED OF RI AN APPROVED' MANNER. ROCK BERM 639-1 4/1/88 APPLICANT: CITY OF ROUND R3OCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 14 OF 20 RECOMMENDED--TOE-INMETHOD. STEEL FENCE POSTS. (MAXIMUM .6' SPACING) WOVEN: WrRE StJpPQRT (12 1/2 GAUGE WIRE) NOTES: 1. SILT FENCE SHALL CONFORM TO ENVIRONMENTAL MANUAL, SECTION 1, WATER QUALITY MANAGEMENT, 1.4.2E • SILT FENCE. • 2. STEEL POSTS WHICH SUPPORT THE SILT FENCE SHALL BE INSTALLED ON A SUGHT ANGLE TOWARD THE ANTICIPATED: -RUNOFF SOURCE. POST MUST. BE EMBEDDED A MIN. OF -ONE (1") FOOT_' 3._ THE TOE OF- THE SILT FENCE SHALL- BE EN TRCHED IN WITH'A SPADE OR MECHANICAL TRENCHER, SO THAT THE DOWNSLOPE .FACE OF THE TRENCH IS FLAT AND, PERPENDICULAR TO THE UNE OF FLOW. WHERE FENCE CANNOT 8E TRENCHED IN (E.G. .PAVEMENT)_ WEIGHT FABRIC FLAP WITH _WASHED. -GRAVEL ON UPHILL SIDE TO" PREVENT FLOW UNDER FENCE. 4. THE WENCH MUST BE -A -MINIMUM OF .6 INCHES DEEP.AND_ 6 'INCHES. WIDE TO ALLOW FOR -THE SILT FENCE FABRIC TO BE:. LAID IN THE GROUND AND.EliCtiELED WITH COMPACTED. MATERIAL. • • 5. SILT FENCE SHOULD BE .SECURELY FASTENEQ TO EACH . STEEL SUPPORT POST' OR TO WOVEN WIRE. WHICH IN :TURN IS ATILACHED• TO THE •STEEL FENCE. POST. 6. INSPE CT1ON SHALL BE 'MADE WEEKLY OR AFTER H RAINFALL ANT AND REPAIR OR REPLACEMENT .SHALL • BE - - MADE PROMPTLY AS 'NEEDED. 7. SILT FENCE SWILL BE REMOVED WHEN THE SITE IS COMPLETELY STABIUZED SO AS NOT TO BLOCK OR 'IMPEDE STORK FLOW OR DRAINAGE. . 8: ACCU IOLATED • SILT SHALL BE REMOVED WHEN TT REACHES /L DEPTH, OF 6 INCHES. THE ;SILT 'SHALL BE DISPOSED OF IK AN APPROVED 'SITE AND . IN SUCH A MANNER. AS TO 'NOT CONTRIBUTE TO ADDITIONAL SILTATION • -4:-..ity• tit '1,1.0114 0 Scole: N,.T.S. )Cia Oat* awn by: B. ORTIZ. SILK" FENCE DETAIL UET NO. APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 15 OF 20 STREET R.O.W. 50' MINIMUM. RRATO ROADWAY. .0 t5 GRADE TO PREVENT RUNOFF FROM LEAVING SITE. ' NOTES: ' I. STONE SIZE SHALL 8E 3' - 5' OPEN GRADED, ROCK. 2. THICKNESS OF CRUSHED STONE PAD TO BE NOT LESS THAN 8". 3. LENGTH SHALL BE A MINIMUM OF 50' FROM ACTUAL ROADWAY. AND WIDTH NOT LESS THAN FULL WIDTH OF INGRESS/EGRESS. 4. ENTRANCE SHALL BE PROPERLY GRADED TO PREVENT RUNOFF FROM LEAVING THE CONSTRUCTION SITE. THE ENTRANCE SHALL BE MAINTAINED IN A CONDITION WHICH WILL PREVENT TRACKING OR FLOWING OF SEDIMENT ONTO PUBUC RIGHTS OF WAY. ALL SEDIMENT SPILLED. DROPPED, WASHED OR TRACKED ONTO PUBUC *RIGHTS • OF WAY MUST BE REMOVED IMMEDIATELY 8Y CONTRACTOR. AS NECESSARY, WHEELS MUST BE CLEANED TO REMOVE SEDIMENT PRIOR TO ENTRANCE ONTO PUBUC RIGHT OF WAY. WHEN WASHING IS REQUIRED, IT SHALL BE DONE ON AN AREA STABIUZED WITH CRUSHED STONE WHICH DRAINS INTO AN APPROVED SEDIMENT TRAP OR SEDIMENT BASIN. ALL SEDIMENT SHALL 8E PREVENTED FROM ENTERING ANY STORM DRAIN. DITCH OR WATERCOURSE USING APPROVED METHODS. B f EXISTING GRADE. ttCiiq of +lluunb ?.ark Scab: N.T.S. 'OoIq Drown b. B. ORTIZ STABILIZED CONSTRUCTION ENTRANCE DETAIL DETAIL NO. APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 16 OF 20 • -12,a45. : Amt: • • . ..!"Yr-•'• 4:zigt.,;.„ .4-.- . -1..z. ... ..m.0....i.. • v 1 I I.. :C.vamt..ftbt,...lindq".. -411.• • . . . . sol..• at.... dtra..r.... ---,.....ic. --ct... • Aim . „ii.i. ...c.-. se. - ..c.: •••=-...o..ge,...0.......=•,. • - - =MD .4; .dittir! A=1 • • ALI., ri"?.." . 1,417k* .66.• • .0.1472‘ -we • -ce• -4510; 0 • .oCtalP _ • -cec. • :•!c,i'll'-.4cAies • - • • ACC• '.'"-aza • .4111,..C! 411.„1, ripe • • Alt,r: 2. '401*. • , • a=r • • .01-• --Ate • UNE - b4i-STiNG 4REE: . ostow-.6.A. , -• 4", TREE. pRoWtot4 DEWL APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 17 OF 20 30' VEGETATED BUFFER SHALLOW POOL MITIGATION CHANNEL N.T.S. PROPOSED MITIGATION CROSS-SECTION °/ SEGMENT 2 30' VEGETATED BUFFER APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 18 OF 20 1 \ \ APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY; TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 IPARIAN PROTECTION ZON SHEET 19 OF 20 C., APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 20 OF 20 • (� Attachment 1 - Dredge and Fill Certification USACE Permit No. 200200684 August 5, 2005 Page1 of 2. WORK DESCRIPTION: As described in the public notice dated September 24, 2004, and the July 7, 2005, Decision Document. SPECIAL CONDITIONS: None. GENERAL: This certification, issued pursuant to the requirements of Title 30, Texas Administrative Code, Chapter 279, is restricted to the work described in the application or joint public notice and shall expire five years from the date of issuance of the Corps of Engineers (COE) permit This certification may be extended to any minor revision of the COE permit when such change(s) would not result in an impact on water quality. The Texas Commission of Environmental Quality (TCEQ) reserves the right to require full joint public notice on a request for minor revision. The applicant is hereby placed on notice that any activity conducted pursuant to the COE permit which results in a violation of the state's surface water quality standards may result in an enforcement proceeding being initiated by the TCEQ or a successor agency. STANDARD PROVISIONS: These following provisions attach to any permit issued by the Corps of Engineers and shall be followed by the permittee or any employee, agent, contractor, or subcontractor of the permittee during any phase of work authorized by a Corps permit. The water quality of wetlands shall be maintained in accordance with all applicable provisions of the Texas Surface Water Quality Standards including the General, Narrative, and Numerical Criteria. 2. The applicant shall not engage in any activity which will cause surface waters to be toxic to man, aquatic life, or terrestrial life. 3. Permittee shall employ measures to control spills of fuels, lubricants, or any other materials to prevent them -from entering a watercourse. All spills shall be promptly reported to the TCEQ, Emergency Spill Response, at (512) 463-7727. 4. Sanitary wastes shall be retained for disposal in some legal manner. Marinas and similar operations which harbor boats equipped with marine sanitation devices shall provide state/federal permitted treatment facilities or pump out facilities for ultimate transfer to a permitted treatment facility. Additionally, marinas shall display signs in appropriate locations advising boat owners that the discharge of sewage from a marine sanitation device to waters in the state is a violation of state and federal law. 5. Materials resulting from the destruction of existing structures shall be removed from the water or areas adjacent to the water and disposed of in some legal manner. 6. A discharge shall not cause substantial and persistent changes from ambient conditions of turbidity or color. The use of silt screens or other appropriate methods is encouraged to confine suspended particulates. 7. The placement of any material in a watercourse or wetlands shall be avoided and placed there only with the approval of the Corps when no other reasonable alternative is available. If work within a wetland is unavoidable, gouging or rutting of the substrate is prohibited. Heavy equipment shall be placed on mats to protect the substrate from gouging and rutting if necessary. 8. Dredged Material Placement: Dredged sediments shall be placed in such a manner as to prevent any sediment runoff onto any adjacent property not owned by the applicant. Liquid runoff from the disposal area shall be retained on-site or shall be filtered and returned to the watercourse from which the dredged materials were removed. Except for material placement authorized by this permit, sediments from the project shall be placed in such a manner as to prevent any sediment runoff into waters in the state, including wetlands. •At`achment 1 - Dredge and Fill Certification USACE Permit No. 200200684 August 5, 2005 Page 2 of 2 9 If contaminated spoil that was not anticipated or provided for in the permit application is encountered during dredging, dredging operations shall be immediately terminated and the TCEQ, Emergency Spill Response, shall be contacted at (512) 463-7727. Dredging activities shall not be resumed until authorized by the Commission. 10. Contaminated water, soil, or any other material shall not be allowed to enter a watercourse. Noncontaminated storm water from impervious surfaces shall be controlled to prevent the washing of debris into the waterway. 11. Storm water runoff from construction activities that result in a disturbance of one or more acres, or are a part of a common plan of developmentthat will result in the disturbance of one or more acres, must be controlled and authorized under Texas Pollutant Discharge Elimination System (TPDES) general permit TXR150000. A copy of the general permit, application (notice of intent), and additional information is available at: http://www.tnrcc.state.tx.us/permitting/waterperm/wwperm/construct.htm1 or by contacting the TCEQ Storni Water & Pretreatment Team at (512) 239-4433. 12. Upon completion of earthwork operations, all temporary fills shall be removed from the watercourse/wetland, and areas disturbed during construction shall be seeded, riprapped, or given some other type of protection to minimize subsequent soil erosion. Any fill material shall be clean and of such composition that it will not adversely affect the biological, chemical, or physical properties of the receiving waters. 13. Disturbance to vegetation will be limited to only what is absolutely necessary. After construction, all disturbed areas will be revegetated to approximate the pre -disturbance native plant assemblage. 14. Where the control of weeds, insects, and other undesirable species is deemed necessary by the permittee, control methods which are nontoxic to aquatic life or human health shall be employed when the activity is located in or in close proximity to water, including wetlands. 15. - Concentrations of taste and odor producing substances shall not interfere with the production of potable water by reasonable water treatment methods, impart unpalatable flavor to food fish including shellfish, result in offensive odors arising from the water, or otherwise interfere with reasonable use of the water in the state. 16. Surface water shall be essentially free of floating debris and suspended solids that are conducive to producing adverse responses in aquatic organisms, putrescible sludge deposits, or sediment layers which adversely affect benthic biota or any lawful uses. 17. Surface waters shall be essentially free of settleable solids conducive to changes in flow characteristics of stream channels or the untimely filling of reservoirs, lakes, and bays. 18. The work of the applicant shall be conducted such that surface waters are maintained in an aesthetically attractive condition and foaming or frothing of a persistent nature is avoided. Surface waters shall be maintained so that oil, grease, or related residue will not produce a visible film of oil or globules of grease on the surface or coat the banks or bottoms of the watercourse. 19. This certification shall not be deemed as fulfilling the applicant's/permittee's responsibility to obtain additional authorization/approval from other local, state, or federal regulatory agencies having special/specific authority to preserve and/or protect resources within the area where the work will occur. EXHIBIT C Mitigation Plan PROJECT MITIGATION PLAN FOR DRY BRANCH TRIBUTARY CHANNEL IMPROVEMENT PROJECT CITY OF ROUND ROCK WILLIAMSON COUNTY, TEXAS. USACE PROJECT NO: 200200684 Revised May 2005 Project Mitigation Plan BASELINE INFORMATION The City of Round Rock proposes to construct channel modifications for a Dry Branch tributary to correct problems of bed scour and •bank -stability, as well as -to address concerns of public .. safety associated with flooding. All practicable options for avoidance, minimization, and mitigation of impacts to wetlands were exercised during design of the proposed project. The proposed project includes deeper excavation into the native bedrock and soil substrate, which would form the bottom of the improved channel. Side slopes (outside of the channel width) would be reinforced with stone where necessary. This excavation would continue downstream to the tributary's intersection with Dry Branch. Minor bank stabilization activities are proposed within a portion of a previously channelized section of the Dry Branch tributary between Gattis School Road and thesection to be deepened (see Sheets 3 and 4 of 20 in permit application). This alternative would increase capacity while utilizing a "self -mitigating" approach. This self -mitigating approach will beaccomplished by excavating a meander channel with an integral riffle/pool segment sequence to enhance stream function accompanied by tree plantings adjacent to Segment 2. The channel design would include a back -slope swale designed to encourage drainage of the overflow areas following a bankfull storm event, as well as a re- formed soil bed exhibiting herbaceous plants: The project would impact one water of the U.S. (an unnamed tributary to Dry Branch) both permanently and temporarily. No wetlands will be impacted. A total of 2.24 acres of waters of the U.S. would be impacted. Compensation for unavoidable permanent and temporary impacts will be accomplished through use of a self -mitigating channel design, riparian plantings adjacent to the channel, and creation of a Riparian Preservation Zone (RPZ) along a neighboring creek in the Brushy Creek watershed.. (1) Avoidance and Minimization Avoidance and minimization measures have been considered for this project to the maximum extent practicable during the planning and design phases for this project. The no -build alternative was .consideredbuteliminated early on in the ....process _as it would not meet ---the purpose and need of correcting existing problems of bed scour and bank stability, or address concerns of public safety associated with flooding. City of Round Rock --Dry Branch Tributary Improvements) USACE Project # 200200684 May 2005 Project Mitigation Plan Four alternatives, including the no -build alternative were studied. After study of the alternatives, the preferred was selected based primarily on the need to correct existing problems of bed scour and bank stability, and address concerns of public safety associated with flooding. Originally an alternative was investigated which consisted of simply deepening the existing channel and using a "traditional" trapezoidal design for the deepened channel. While practicable this alternative did not address stream dynamics issues and was ultimately abandoned. Another previous alternative included a proposal to line a portion of the channel with concrete. Following an April 4, 2003, field visit, the USACE—Fort Worth District office provided feedback indicating that this would result in numerous concerns from the regulatory community and was not advisable. Based on this correspondence, the project design was revised to remove the concrete component from the proposed action. The recommended preferred alternative is described in greater detail in this permit application and mitigation plan. (2) Impacts Direct permanent impacts will consist of the deepening of existing jurisdictional channels and the placement of earthen fill in jurisdictional areas. Temporary impacts will consist of vegetation removal and earth moving in jurisdictional areas that will be restored once construction is completed. The portions of the existing channel (Segment 2) for Dry Branch Tributary within the limits of the proposed channel will be completely excavated and will cease to be an unaltered natural drainage. The tributary will follow the path of the proposed channel that connects previous channel improvements upstream (Segment 3) and downstream (Segment 1). The approximately 112 to -156 foot wide proposed channel (top width) is designed to contain the 100 -yr flood, preempting damage to future residences adjacent to the channel (see Sheet 13 of 20). Portions of the existing channel outside the limits of the proposed channel will be completely filled, regraded and revegetated as necessary. The proposed channel will connect with the previously improved 80 -foot wide (bottom width) earthen channel upstream and the primary Dry Branch channel downstream. This ultimate channel is designed to contain the fully developed 100 -yr flow rate along the entire length of Dry Branch Tributary from its headwaters to its confluence with Dry Branch. City of Round Rock --Dry Branch Tributary lmprovements2 USACE Project # 200200684 May 2005 Project Mitigation Plan (3) Plan Goals and Objectives The goals and objectives for this mitigation plan are to appropriately compensate for impacts to jurisdictional areas that cannot be .avoided or further minimized in the construction of this project. Compensation for unavoidable impacts will be accomplished through a self -mitigating on-site design coupled with additional plantings and protection of a Riparian Protection Zone, as described in this report. (4) Proposed Mitigation Area See Wetland Delineation Report, submitted under separate cover. (5), Jurisdictional Determination See Wetland Delineation Report, submitted under separate cover. (6) Proposed Compensatory Mitigation This project is proposed to be partially self -mitigating. The City proposes to excavate a low flow mitigation channel within Segments 1 and 2, intended to replace some of the lost function and habitat (see Sheet 18 of 20). The proposed low flow channel is approximately 1 foot in depth, includes a sinuous meander and a bottom width of 20 feet with cross slopes of 1% to 2%. The meandering low flow channel includes a series of steep slopes (0.6%) and flat slopes (0%) to encourage a "riffling and pooling" sequence throughout the improvement reach. The downstream end of the "pool" reach includes rock boulders to restrict flow and provide habitat cover. Velocities at low flows (50 to 120 cubic feet per- second, cfs) range from 3 to 6 feet per second (fps). These velocities will encourage the transport of sediment . through the system. and discourage the collection of sediment that may adversely affect conveyance of the channel. The inside bend of the meandering low flow channel includes a "point bar," or "single" floodplain bench (the bottom of themain channel) that will be frequently inundated. The interior side of the bench includes an `overflow" channel that will drain the floodplain bench once floodwaters have receded. The area between the overflow channel and the low flow channel will include a soil bed with a topsoil layer taken from deposits located throughout the existing channel to maintain the existing plant/grass species that have been established. A temporary mat will be required to reinforce the topsoil until vegetation has been established. This area will encourage the uptake of nutrients City of Round Rock --Dry Branch Tributary Improvements3 USACE Project # 200200684 May 2005 Project Mitigation Plan adding a water quality benefit to the system. The bankfull condition would be contained within the rock wall protection at the edges of the channel. The meandering channel would retain the- integrity of the existing stream to the extent possible,. would include riffles and pools where practicable and feasible, and would still maintain the proposed function of the project itself, which is adequate conveyance of storm water. (7) Existing Liens and Encumbrances All property is owned or controlled by the City of Round Rock. (8) Protective Actions Erosion and sedimentation control measures, site work and restoration work shall be in accordance with the City of Round Rock Erosion and Sedimentation Control Ordinance (see Sheets 14 through 17 of 20). All slopes shall be sodded or seeded with approved grass, grass mixtures, or ground cover suitable to the area and season in which they are applied (see table below for proposed seed mix). Silt fences, rock berms, sediment basins or similarly recognized techniques and materials shall be employed during construction to prevent point- source sedimentation loading of downstream facilities. Proposed Erosion Control Seed Mix Common Name Plant Type Scientific Name Application rate (lbs/1000 ft2) Buffalograss Grass Buchloe dactyloides 0.3 Green Sprangletop Grass Leptochloa dubia 0.4 Yellow Indiangrass Grass Sorghastrum nutans 0.2 Little Bluestem Grass :: Schizachyrium scoparium 0.2 Canada Wildrye Grass Elymus canadensis 0.2 Purple Threeawn Grass Aristida purpurea 1.2 Sideoats Grama Grass Bouteloua curtipendula 1.3 Texas Bluebonnet - Wildflower .. Lupinus texensis 1.4 Purple Prairie Clover Wildflower Petalostemum purpurea 0.1 Plains Coreopsis Wildflower Coreopsis tinctoria 0.05 Goldenrod Wildflower Solidago altissima 0.02 Greenthread Wildflower Thelesperma filifolium 0.075 City of Round Rock --Dry Branch Tributary 1mprovement.4 USACE Project # 200200684 . May 2005 Project Mitigation Plan Common Name Plant Type Scientific Name Application rate (lbs/1000 ft2) Indian Blanket Wildflower Gaillardia pulchella 0.15 Lemon Mint Wildflower Monarda citriodora -0.06 -, Mexican Hat Wildflower Ratibida columnifera 0.05 Pink Evening Primrose Wildflower Oenothera speciosa 0.02 Annual Sunflower Wildflower Helianthus annuus 0.075 (9) Hydrologic Information All construction is along the bottom and side slopes of the excavated floodway. (10) Mitigation Area Substrate The area between the overflow channel and the low flow channel will include a soil bed with a topsoil layer taken from deposits located throughout the existing channel to maintain the existing plant/grass species that have been established. A temporary mat will be required to reinforce the topsoil until vegetation has been established. This area will encourage the uptake of nutrients adding a water quality benefit to the system. (11) Planting Plan Stream Channel Mitigation Measures The meandering channel would retain the integrity of the existing stream to the extent possible, would include riffles and pools where practicable and feasible, and would still maintain the _ proposed function of the project itself, which is adequate conveyance of storm water. In addition to the replacement of stream function, an attempt would be made to replace the lost riparian vegetation and habitat within a 30 -foot vegetated buffer (see Figures 1-3) along both sides of the proposed channel adjacent to Segment 2 (totaling approximately 5.5 acres). The 30 -foot buffer would be populated with native trees and plants in accordance with the attached species list (a subset of the City's List of Approved Trees for Round Rock). The vegetated buffer would be designed and planted with a target survival rate of 50% and a target density of approximately. 160- trees per acre. Plantings would consist of bare root or potted seedlings as available and would be planted by hand. City of Round Rock --Dry Branch Tributary Improvemenls5 USACE Project # 200200684 May 2005 Project Mitigation Plan Additionally, the City proposes to stockpile the seed bank/topsoil from the areas to be excavated for the proposed project and use this seed bank to reseed portions of the bed of the channel. This will be accomplished by stockpiling approximately the surface four inches of the excavated areas which containdesirable species, excluding those areas containing cattails or other undesirable species, and replacing this topsoil in portions of the channel bed after construction. Additional Riparian Woodland Plantings In addition to the self -mitigating nature of the channel design as described above the City proposes planting trees in several areas adjacent to the proposed project. Three areas where additional riparian tree plantings are proposed are indicated in the drawings on Figure 3. These areas total approximately 3.26 acres. The City also proposes to plant a line of trees on the side slopes along both sides of the stream in Segments 1 and 3. The planted trees would be staggered and planted at an approximately 15 -foot spacing, on center. Trees planted in all these areas would be native species in accordance with the attached list (a subset of the City's List of Approved Trees for Round Rock). Establishment of Riparian Preservation Zone (RPZ) In response to resource agency comments, the City proposes to create a.high-quality Riparian Preservation Zone (RPZ) as additional compensatory mitigation for project -related impacts. The RPZ consists of approximately 8.25 acres (1,550 linear feet) on both sides of Lake Creek approximately 1/4 mile north of the Dry Branch tributary (see Figure 4). Lake Creek within the RPZ has an ordinary high water mark of approximately 25 feet. The perennial creek lies within a riparian corridor approximately 150 to 200 feet wide. The streambed is between bluff banks approximately 30 feet lower than the top of the banks. It is presently wooded with a canopy cover of approximately 80%. Dominant canopy species are live oak (Quercus virginiana), cedar elm (Ulmus crassifolia), Ashe juniper (Juniperus ashen), pecan (Carya illinoensis), Osage orange (Madura pomifera), and black willow (Salix nigra). Diameters at breast height (dbh) range from 6 to 40 inches and average approximately 10 inches while heights range. from 15 to 45 feet and average approximately 30 feet. The shrub/sapling layer is dominated by canopy species saplings, red buckeye (Aesculus pavia) and deciduous holly (Ilex decidua). Common vines include greenbrier (Smilax sp.), Japanese honeysuckle (Lonicera japonica), and poison ivy (Toxicodendron radicans). Dominant herbaceous species include Canada wildrye (Elymus canadensis), Johnson grass (Sorghum_ halepense), and curly dock (Rumex crispus). A hike and bike trail will be constructed in this area outside the 100 -year floodplain. Otherwise the area will be preserved as it is now, with considerations for periodic maintenance. Photographs of the area are attached at the end of this plan. City of Round Rock --Dry Branch Tributary Improvements6 USAGE Project # 200200684 May 2005 Project Mitigation Plan (12) Planting Success Criteria Herbaceous Communities The City proposes a goal of 80% groundcover in the floodplain bench soilbed after 3 years. To.,. ensure reaching these goals the soil bed will be monitored with a monitoring report to be submitted to the U.S. Army Corps of Engineers — Fort Worth District annually for 3 years (beginning in the year construction is completed). These reports will be submitted to the Corps by October 1 each year. If these plantings do not meet the goals stated above supplemental plantings will be performed. In addition, the erosion control and bank stabilization measures proposed within Segment 3 comprise a beneficial enhancement to the aquatic environment. Woody Communities An attempt would bemadeto .replace the lost. riparian vegetation and habitat within a 30 -foot vegetated buffer along both sides of the proposed channel adjacent to Segment 2 (totaling approximately 5.5 acres). The 30 -foot buffer (see Figures 1-3) would be populated with native trees and plants in accordance with the attached species list (a subset of the City's List of Approved Trees for Round Rock). Three areas where additional riparian tree plantings are proposed are indicated on Figure 3. These areas total approximately 3.26 acres. The woody species plantings would be designed and planted with a target survival rate of 50% and a target density of approximately 160 trees per acre. No single species would constitute more than 30% of the surviving plantings. The City also proposes to plant a line of trees on the side slopes along both sides of the stream in Segments 1 and 3. The planted trees would be staggered and planted at an approximately 15 - foot spacing, on center. Trees would be native species would be from the City's list of Medium Trees, and would be replaced if mortality exceeds 15%. Maintenance The City will mechanically mow accessible portions of the channel side -slopes and vegetated. areas within the channel on a yearly basis in order to remove any impediments to conveyance, such as woody species (other than planted trees/shrubs). In addition, undesirable invasive species and woody species not accessible to mowers will be manually treated with appropriate herbicides in order to minimize the occurrence of these species, (13) Performance Standards The permittee will maintain the mitigation area so that the water of the U.S. is functioning at the City of Round Rock --Dry Branch Tributary Improvements? USACE Project # 200200684 May 2005 Project Mitigation Plan level of ecological performance described in (11) to ensure that: • Waters of the U.S. are functioning as the intended type of waters of the U.S. and at the level of ecological performance prescribed in the mitigation plan. • Buffer and riparian zones and other areas integral to the enhancement of the aquatic ecosystem are functioning as the intended type of ecosystem component and at the level of ecological performance prescribed in the mitigation plan. (14) Ecological Benefits The mitigation plan as proposed would create a more diverse habitat in the portions of the project area that are already channelized while lessening erosion from flood events. (15) Threatened and Endangered Species A search of the map repository of sensitive species and community types maintained by the Natural Diversity Database (NDD) at the Texas Parks and Wildlife Department (TPWD) was performed in February 2004 to encompass the project area. No known endangered, threatened, or otherwise rare or sensitive plant species, animal species or community type occurrences have been reported within or immediately adjacent to the impact area. No habitat for listed species occurs on the site. No impacts are anticipated. (16) Additional Relevant Information A cultural resource investigation found no archeological sites or Section 106 issues (letter from THC provided to USACE in original permit submittal). No significant ecologically sensitive areas occur within the project's area of potential effect. Construction of the proposed channel, as proposed, would minimize impacts to regional hydrology. (17) Operation and Management Plan Once success criteria for the mitigation areas (soil bed and woody plantings) are met these sites will be maintained in perpetuity. The portions of the project area where woody species are not planted will be mowed by the City twice a year. All structures will be maintained by the City. City of Round Rock --Dry Branch Tributary Improvement38 USACE Project # 200200684 May 2005 Project Mitigation Plan (18) Monitoring Plan Mitigation progress shall be measured in two ways: (a). Vegetative enhancements will be monitored. as outlined in (11) and (12), above; and (b). Proposed channel features as described in this document will be monitored and documented in the yearly reports outlined in (19), below. Contingency Plan Compensatory over planting of desirable species is designed to lessen the probability that success criteria are not met. In the event that success criteria for this mitigation plan are not met steps will be taken to ensure that they are met in the future (replanting, etc.). (19) Reporting Plan An annual report will be submitted to the USACE by the City on or before the first of October detailing the status of the mitigation plan and activities taking place in the preceding year. This annual report will be submitted for a minimum of three consecutive years, beginning in the year construction takes place. (20) Mitigation Specialist The City of Round Rock will contract with or employ a qualified mitigation specialist to oversee implementation of this plan. (21) Schedule Construction is scheduled to begin in early 2005 (originally scheduled for 2004). Project mitigation will occur contemporaneous with construction of the channel modifications and plantings are expected to be completed by March 2007. It is anticipated that construction will be completed in mid- to late- 2005, with the first of three monitoring reports submitted by October 1, 2005. (22) Provision for a Protective Covenant The property will remain in City of Round Rock ownership/control in perpetuity. The Riparian Preservation Zone (RPZ) shown in Figure 4 will be protected by deed restriction, with stipulations made for long-term maintenance and future construction of a hike and bike trail. City of Round Rock --Dry Branch Tributary lmprovements9 USACE Project # 200200684 May 2005 EXISTING UPSTREAM CHANNEL IMPROVEMENT Base Map Source: USGS 7.5 Mn Topographical Quadrangle of Round Rock, TX (1987) & Pflugerville West, TX (1987) - . . N Scale: 1' = 2000' • PREVIOUSLY CHANNELIZED AREA AREA NOT PREVIOUSLY CHANNELIZED APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNEL1ZATION PROJECT #: 200200684 DATE: MAY 2005 MITIGATION PLAN FIGURE 1 30VEGETATED BUFFER 430' VEGETATED BUFFER N.T.S. MITIGATION CHANNEL PROPOSED MITIGATION CROSS-SECTION / SEGMENT 2 i APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: MAY 2005 MITIGATION PLAN FIGURE 2 _ •r _ Oe _�O�jh 4b/ /Aec Or -J i \"1o7i i /'k ,r 0 s W z L J tat Q r K W x 30 FOOT BUFFER AREA MIMOSA TRAif APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: MAY 2005 w ce 0 z_ 1- 4z a MITIGATION PLAN FIGURE 3- P Ili ILI LI) 2 :---..., / ; .:-• ._,....., --,- ..---,..---.-„- - r ,.,;=. i--°:...' .?.,-..'•-• -- :,,.., ,..- -.. .. --... , z.-. w 6, - "------ ....- rt 44, l , .„,..--;;.., .,.. C.) 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' • , . • •-•• 2Sc 411 -- — I • APPLICANT CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: MAY 2005 - - - RIPARIAN PROTECTION ZONE MITIGATION PLAN FIGURE 4 LIST OF APPROVED NATIVE TREES FOR ROUND ROCK Common Name Large Trees (mature height 40 feet or more) Bur Oak Live Oak Chinquapin Oak Shumard Red Oak Cedar Elm Pecan Bald Cypress Montezuma Cypress Eastern Black Walnut Southern Magnolia Post Oak American Elm Scientific Name Quercus macrocarpa Quercus virginiana Quercus muehlenbergii Quercus shumardii Ulmus crassifolia Carya illinoensis Taxodium distichum Taxodium mucronatum Juglans nigra Magnolia grandiflora Quercus stellata Ulmus americana Medium Trees (mature height 25-40 feet) Texas (Spanish) Red Oak Lacey Oak Texas Ash Mesquite Western Soapberry Escarpment Black Cherry Bigtooth Maple Carolina Cherry Laurel Texas (Little) Walnut Eastern Red Cedar Quercus buckleyi Quercus laceyi Fraxinus texensis Prosopis glandulosa Sapindus drummondii Prunus serotina ssp. Eximia Acer grandidentatum Prunus caroliniana Juglans macrocarpa Juniperus virginiana Small Trees (mature height 8-25 feet) Texas Redbud Mexican Plum Mountain Laurel Mexican Buckeye Yaupon Holly Texas Persimmon Vitex Desert Willow Possumhaw Holly Carolina Buckthorn Eve's Necklace American Smoke Tree Blanco Crab Apple Flameleaf Sumac Texas Pistache Wax Myrtle Texas Madrone Rough -leaf Dogwood Cercis canadensis Prunus mexicana Sophora secundiflora Ungnadia speciosa Ilex vomitoria Diospyros texana Vitex spp. Chilopsis linearis Ilex decidua Rhamnus caroliniana Sophora affinis Cotinus obovatus Pyrus ioensis Rhus copallina Pistacia texana Myrica cerijera Arbutus xalapensis Cornus drummondii 1. A.W. Grimes bridge over Lake Creek. 2. Lake Creek from top of bluff on south side. PAGE 1 OF 3 3. Large pooled area of Lake Creek. 4. Looking northwest from creek bank up slope through riparian area of Lake Creek. PAGE 2 OF 3 5. Lake Creek, looking downstream. 6. Lake Creek, looking upstream. PAGE 3 OF 3 EXHIBIT D Dry Branch Project (DR Horton and CoRR Responsible Portions of the Project) Oretatil ierr '�:45uiii�i 4),As 4/11111111. ofmnannu �Iliftllll�� nI 111111111.1111411111 -��- onO 1.1% drelhHann 1111111111111. ir /nnnmGt 3.01011111/1* IP Q ►�1rvfA hili _ �i!�i_ �i��i� �i.I�►��\,� _.��I,\1i e..ps, 10 ��=� Ki tq v1 1410 Pa: _VIlla LI le%I1t11►te:11 mown .i i�v �e Vl • - -- -- - - - ft WI -. - M - - -- - r ■ Ila -r.--r UMlilli11111111M111 OMIllIMPE 11111111 , unuun 4---_■(LI1111!llllllli i -s ■ �'► tet. almu \HI MIN EXHIBIT E Performance Bond from D.R. Horton EXHIBIT F Riparian Tree Plantings APPLICANT CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: APRIL 2005 MITIGATION PLAN FIGURE 3 EXHIBIT G Riparian Protection Zone 5 cow z. w<a K N V < di ul q n `n.,a ^d� 0 rt \,EP4\ m M TAM » I , 1 II� T1 < n /N n Un oar `^›-% amF ci oft7ZK 0 OQ \ \ \ \ APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 RIPARIAN PROTECTION ZONE SHEET 19 OF 20 11110111111 ''i.._!in /111 usti i IUHI rrr� A,. ttlt�ttlt® ire NIOUNIONFA Ass boss sti MHO so •a R P awl �.■.— . • 4 WS mix >-- ot gag m .. EAm :11 fions. mg Oa "ear= -ell 111r511rMMrl•111 N�j 11111111111111111111 +lssr rt 111Itf�lNfs�rfrN� :. ■IiIiiinssusr :■11� rN11�11MSliaNal Ems11111111VA— MS NI 1:\Engmeenng\CouncIl Maps\DryBranchs.G.Improv.mxa DATE: November 21, 2005 SUBJECT: City Council Meeting - December 1, 2005 ITEM: 9.C.1. Consider a resolution authorizing the Mayor to execute a Development Agreement with Continental Homes of Texas, L.P. for the construction of channel improvements and the implementation of a mitigation plan for the Dry Branch (South Creek Channel) Improvements Project. Department: Engineering & Development Services Staff Person: Daniel L. Ha[den, P.E., City Engineer Justification: This project includes the construction of approximately 6,540 linear feet of Dry Branch tributary to correct problems of bed scour and bank stability, as well as to address concerns of public safety associated with flooding. The Dry Branch Project will impact 2.24 acres of waters of the U.S., and as a result, the City has undertaken to secure a permit from the Corps of Engineers having jurisdiction over the Dry Branch project. The City of Round Rock is constructing the channel modifications on approximately 4,160 linear feet and D.R. Horton, the developer of the Turtle Creek subdivision, is constructing channel modifications on approximately 2,380 linear feet of the channel. Because the City of Round Rock is the only applicant for the permit, this Developer Agreement with D.R. Horton is to ensure the permitted activities for this project are completed by both parties in a timely manner. Funding: Cost: None Source of funds: Not Applicable Outside Resources: D.R. Horton Continental Homes of Texas, L.P. Background Information: The Dry Branch Project will consist of widening approximately 4,000 linear feet of natural stream channel, construction of a low flow channel in approximately 2,540 linear feet of previously channelized stream channel, and implementation of a mitigation plan concurrently with construction and operation of the Dry Branch project to offset adverse impacts to waters of the U.S. Public Comment: The City has discussed the proposed project with several residents in the South Creek subdivision. A neighborhood meeting will be conducted prior to the commencement of construction for residents whose property is adjacent to the Dry Branch. DEVELOPMENT AGREEMENT This DEVELOPMENT AGREEMENT ("the Agreement") is made and entered into on _7r this the J day of the month of 6i , , 2005, by and between the CITY OF ROUND ROCK, TEXAS, a home rule municipal corporation ("City"), and CONTINENTAL HOMES OF TEXAS, L.P., a Texas limited partnership, ("Continental"), and its successors and assigns. RECITALS: WHEREAS, the parties desire to construct channel modifications for Dry Branch tributary to correct problems of bed scour and bank stability, as well as to address concerns of public safety associated with flooding ("Dry Branch Project") as shown on Exhibit A attached hereto and made a part hereof by reference for all appropriate purposes; and WHEREAS, the Dry Branch Project will impact 2.24 acres of waters of the United States both permanently and temporarily and as a result the City has undertaken to secure a permit ("404 Permit") from the Corps of Engineers having jurisdiction over the Dry Branch Project as set forth in Exhibit B attached hereto and made a part hereof by reference for all appropriate purposes; and WHEREAS, the 404 Permit requires the City to comply with the terms of the General and Special Conditions contained within the 404 Permit and the Texas Commission on Environmental Quality Section 401 Water Quality Certification, dated August 5, 2005 (TCEQ Certification") ; and WHEREAS, the City, as a condition to allowing any work to be performed on the Dry Branch Project, must require compliance with the General and Special Conditions and the TCEQ Certification contained in the 404 Permit by all parties, their contractors and subcontractors performing the permitted activities for the Dry Branch Project; and WHEREAS, City and Continental desire to enter into this Agreement to set forth in writing certain covenants and conditions, and to set forth their whole agreement; NOW, THEREFORE, for and in consideration of the mutual covenants contained herein and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, City and Continental agree as follows: AGREEMENT 1. Dry Branch Project. The Dry Branch Project will consist of the following: (a) widening of 4,000 linear feet of natural stream channel; (b) construction of a low flow channel and adjacent floodplain bench in 2,540 linear feet of previously channelized stream channel; and 0009240 1/bbw R -oma gel (c) implementation of a mitigation plan concurrently with construction and operation of the Dry Branch Project to offset adverse impacts to the waters o f the United States such Mitigation Plan ("Mitigation Plan") being attached hereto as Exhibit C and made a part hereof by reference for all appropriate purposes. 2. Effective Date. This Agreement shall be effective on the date it has been signed by the City of Round Rock. 3. Construction and Completion of Dry Branch Project. Continental and the City agree to be responsible for all costs of development and construction for their respective portions of the Dry Branch Project shown on Exhibit L attached hereto and made a part hereof by reference for all appropriate purposes. The parties agree that all construction shall be done in full conformance with the terms and conditions set forth in the 404 Permit and the Mitigation Plan, as well as all other laws or regulations. Continental agrees to secure and pay for all necessary additional permits and licenses required for its performance of the Dry Branch Project. The parties agree that construction of the Dry Branch Project will timely commence and be completed, and will be accepted by City, by December 31, 2007. Subject to the warranty set forth below and Mitigation Plan requirements, once the referenced construction has been accepted by City, City agrees to thereafter maintain the improvements and release Continental from any on-going maintenance responsibility regarding the channel. 4. Warranty. Following completion and acceptance, Continental agrees to provide a three (3) year warranty to City coextensive with that required under the terms of the 404 Permit. Said warranty will provide that all Mitigation Plan activities, including tree and other vegetation plantings of whatever kind or nature and the planting success criteria will comply with the terms of both the 404 Permit and the City's ordinances. 5. Bond. Continental understands and agrees to secure a performance bond, the form of which is attached hereto as" Exhibit E and made a part hereof by reference for all appropriate purposes, in the amount of Eight Hundred Thousand Dollars ($800,000.00) as part of this Agreement. Such performance bond shall have a term of one year following completion of the Dry Branch Project by Continental and acceptance by the City. 6. Stipulations by Parties. The parties agree, and Continental explicitly stipulates, that as part of the Mitigation Plan, approximately 3.26 acres of Continental property, as shown more fully on Exhibit F, attached hereto and made a part hereof by reference for all appropriate purposes, shall be utilized solely for additional riparian tree plantings. Continental further stipulates that it will enter into a Conservation Easement with the City whereby Continental's portion of approximately 8.361 acres along Lake Creek, approximately 1/4 mile north of the Dry Branch tributary, as shown more fully on Exhibit G, attached hereto and made a part hereof by reference for all appropriate purposes, shall become a high-quality Riparian Preservation Zone which will thereafter remain under the City's control in perpetuity. Continental stipulates and agrees to provide any information that may be necessary for any ongoing reports that may be required under the terms of the 404 Permit, the Mitigation Plan or the TCEQ Certification. 2 7. No Partnership. This Agreement will not be construed in any form or manner to establish a partnership, joint venture or agency, express or implied, nor any employer-employee or borrowed servant relationship by and among the parties. 8. Notice. All notices and other communications in connection with this Agreement shall be in writing and shall be considered given as follows: (i) when delivered personally to the recipient's address as stated in this Agreement; or (ii) when sent, by certified or registered mail, return receipt requested, to the recipient's address as stated in this Agreement. The addresses of the parties provided below may be changed by similar notice in writing given by the party whose address is to be changed. For the purposes of this Section 8, the addresses of the parties for all notices are as follows: If to City: With a copy to: If to Continental: With a copy to: 9. Miscellaneous. City of Round Rock, Texas Attention: James R. Nuse, P.E., City Manager 221 East Main Street Round Rock, TX 78664 Stephan L. Sheets, City Attorney Sheets & Crossfield, P.C. 309 East Main Street Round Rock, TX 78664 Continental Homes of Texas, L.P. Attention: Richard N. Maier 12554 Riata Vista Circle, Second Floor Austin, Texas 78727 (a) Force Majeure. Neither City nor Continental shall be deemed in violation of this Agreement if it is prevented from performing any of its obligations hereunder by reasons for which it is not responsible or circumstances beyond its control. However, notice of such impediment or delay in performance must be timely given and all reasonable efforts undertaken to mitigate its effects. (b) Assignment. This Agreement may not be assigned without the prior express written consent of the other party, which consent shall not be unreasonably, withheld, conditioned or delayed. 3 (c) Modification This Agreement may not be modified or amended except by a subsequent agreement in writing signed by both parties. (d) Binding Effect. This Agreement will be binding upon and inure to the benefit of the parties hereto and their respective successors, legal representatives and assigns. (e) Entire Agreement. This Agreement and all exhibits attached hereto, plus any referenced site plans and construction plans, constitute the entire agreement and understanding between the parties and supersede all prior and contemporaneous agreements and understandings of the parties in connection therewith. (f) Governing Law. This Agreement will be construed and interpreted in accordance with the laws of the State of Texas and venue for any legal proceedings instituted regarding this Agreement will be in Williamson County, Texas. (g) Captions. The captions in this Agreement are inserted for convenience of reference only and in no way define, describe or limit the scope or intent of this Agreement or any provisions hereof. (h) Gender and Number. Words of any gender used in this Agreement will be construed to include the other gender and words in the singular number will be construed to include the plural, and vice versa, as the context may require herein. (i) Multiple Counterparts. This Agreement may be executed in a number of identical counterparts which, taken together, shall constitute collectively one (1) agreement; but in making proof of this Agreement, it shall not be necessary to produce or account for more than one such counterpart. - Signature Block on the following page - 4 EXHIBIT A Dry Branch Project EXECUTED on this the / $1day of 171 , 2005. ATTEST: Christine R. Martinez, City Secreta APPROVED AS TO FORM: e Steph. . Sheets, City Attorney CITY OF ROUND ROCK, TE By: P ' ane: e Maxwell Title: Ma or Date: Of et, CONTINENTAL HOMES OF TEXAS, L.P., a Texas limited partnership By: CHTEX of Texas, Inc., a Delaware corporation, its sole general partner 5 By:, RichArd N. Maier Title: Vice -President Date: D Base Map Source: USGS 7.5 Min. Topographical Quadrangle of Round Rock (1987) & Pllugervitle West (1987) •Project Area SCALE: 1" = 2000' DRY BRANCH TRIBUTARY CHANNEL IMPROVEMENTS PROJECT LOCATION APPLICANT: CITY OF ROUND ROCK; WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 1 OF 20 EXHIBIT B Department of Army Permit DEPARTMENT OF THE ARMY PERMIT Permittee City of Round Rock, Texas Permit No. 200200684 Issuing Office Fort Worth District NOTE: The term "you" and its derivatives, as used in this permit, means the permittee or any future transferee. The term "this office" refers to the appropriate district or division office of the Corps of Engineers having jurisdiction over the permitted activity or the appropriate official of that office acting under the authority of the commanding officer. Project Description: Discharge of approximately 5,100 cubic yards of dredged and fill material into 2.24 acres of waters of the United States (6,540 linear feet of perennial stream) associated with the construction of a channelization and stabilization project. Elements of the project include: widening 4,000 linear feet of natural stream channel; construction of a low flow channel and adjacent floodplain bench in 2,540 linear feet of previously channelized stream channel; and implementation of a mitigation plan concurrently with construction and operation of the project to offset adverse impacts to waters of the United States. Project Location: The proposed channelization and stabilization project would be located on a tributary to Dry Branch Creek downstream of Gaddis School Road in the city of Round Rock, Williamson County, Texas. The proposed project would be located approximately at UTM coordinates 628923.248 East and 3375443.635 North (Zone 14) on the Round Rock 7.5 -minute USGS quadrangle map in the USGS Hydrologic Unit 12030102. Permit Conditions: In accordance with attached Sheets 1-20 of 20 and Texas Commission on Environmental Quality Section 401 Water Quality Certification, Pages 1-2 of 2, dated August 5, 2005. General Conditions: 1. The time limit for completing the work authorized ends on December 31, 2010 . If you find that you need more time to complete the authorized activity, submit your request for a time extension to this office for consideration at least one month before the date is reached. 2. You must maintain the activity authorized by this permit in good condition and in conformance with the terms and conditions of this permit. You are not relieved of this requirement if you abandon the permitted activity, although you may make a good faith transfer to a third party in compliance with General Condition 4 below. Should you wish to cease to maintain the authorized activity or should you desire to abandon it without a good faith transfer, you must obtain a modification of this permit from this office, which may require restoration of the area. 3. If you discover any previously unknown historic or archaeological remains while accomplishing the activity authorized by this permit, you must immediately notify this office of what you have found. We will initiate the Federal and state coordination required to determine if the remains warrant a recovery effort or if the site is eligible for listing in the National Register of Historic Places. 4. If you sell the property associated with this permit, you must obtain the signature of the new owner in the space provided and forward a copy of the permit to this office to validate the transfer of this authorization. 5. If a conditioned water quality certification has been issued for your project, you must comply with the conditions specified in the certification as special conditions to this permit. For your convenience, a copy of the certification is attached if it contains such conditions. ENG FORM 1721, Nov 86 EDITION OF SEP 82 IS OBSOLETE. (33 CFR 325 Appendix A)) 6. You must allow representatives from this office to inspect the authorized activity at any time deemed necessary to ensure that it is being or has beenaccomplished in. accordance with .the -terms -.and conditions -of -.your permit. Special Conditions: SEE PAGE 4 (Special Conditions) Further Information: 1 Congressional Authorities: You have been authorized to undertake theactivitydescribed above pursuant to: O Section 10 of the Rivers and Harbors Act of 1899 (33 U.S.C. 403). (x) Section 404 of the Clean Water Act of 1972.(33 U.S.C. 1344). O Section 103 of the Marine Protection, Research and Sanctuaries Act of 1972 (33 U.S.C. 1413). 2. Limits of this authorization. a. This permit does not obviate the need to obtain other Federal, state, or local authorizations required by law. b. This permit does not grant any property rights or exclusive privileges. c. This permit does not authorize any injury to the property or rights of others. d. This permit does not authorize interference with any existing or proposed Federal project. 3. Limits of Federal Liability. In issuing this permit, the Federal Government does not assume any liability for the following: a. Damages to the permitted project or uses thereof as a result of other permitted or unpermitted activities or from natural causes. b. Damages to the permitted project or uses thereof as a result of current or future activities undertaken by or on behalf of the United States in the public interest. c. Damages to persons, property, or to other permitted or unpermitted activities or structures caused by the activity authorizedby this permit. d. Design or constructiondeficiencies associated with the permitted work. e. Damage claims associated with any future modification, suspension, or revocation of this permit. 4. Reliance on Applicant's Data: The determination of this office that issuance of this permit is not contrary to the public interest was made in reliance on the information you provided. 5. Reevaluation of Permit Decision. This office may reevaluate its decision on this permit at any time the circumstances warrant. Circumstances that could require a reevaluation include, but are not limited to, the following: a. You fail to comply with the terms and conditions of this permit. b: The information provided by you in support of your permit application proves to have been false, incomplete, or inaccurate (See 4 above). c. Significant new information surfaces which this office did not consider in reaching the original public interest decision. 2 Such -a -reevaluation may result in a determination that it is appropriate to use the suspension, modification, and revocation procedures_contained_in 33 CFR 325.7 or enforcement procedures such as those contained in 33 CFR 326.4 and 326.5._ The referenced enforcement procedures provide for the issuance of an administrative order requiring you to comply with the terms and conditions of your permit and for the -initiation -of legal action where appropriate. You -will -be- required to pay for any corrective measures ordered by this office, and if you fail to comply with such directive, this office may in certain situations (such as those specified in 33 CFR 209.170) accomplish the corrective measures by contract or otherwise and bili you for the cost. 6. Extensions. General condition 1 establishes a time limit for the completion of the activity authorized by this permit. Unless there are circumstances requiring either a prompt completion of the authorized activity or a reevaluation of the public interest decision, the Corps will normally give favorable consideration to a request for an extension of this time limit. - i'oursignature below, as permittee, indicates that you accept and agree to comply with the terms and conditions of this permit. (PERMITTEE) ......... _... Mr. Michael Thane City of Round Rock, Texas (DATE) This permit becomes effective when the Federal official, designated to act for the Secretary of the Army, has signed below. (FOR THE) (DISTRICT ENGINEER) John R. Minahan Colonel, Corps of Engineers (DATE) When the structures or work authorized by this permit are -still in existence at the time the property is transferred, the terms and conditions of this permit will continue to be binding on the new owner(s) of the property. To validate the transfer of this permit and the associated liabilities associated with compliance with its terms and conditions, have the transferee sign and date below. (TRANSFEREE) (DATE) 3 Special Conditions - Permit Number 200200684 1. The permittee shall implement and abide by the mitigation plan titled "Project Mitigation Plan for Dry Branch Tributary" by Hicks and Company, dated April 2005. The permittee shall implement the mitigation plan concurrently with the construction of the project and complete the initial construction and plantings associated with the mitigation work prior to completion of construction of the project. Completion of all elements of f this mitigation plan is a requirement of this permit. 2. The permittee shall be responsible for maintaining the mitigation areas enhanced and created to comply with Special Condition 1 above until such time as the permittee provides documentation to, and receives verification from, the Regulatory: Branch, Fort Worth District, U. S. Army Corps of Engineers (USACE), that areas within the mitigation area intended to become: a. waters of the United States meet the definition of a waters of the United States under the Regulatory Program regulations applicable on the date of this permit; b. waters of the United States are functioning as the intended type of waters of the United States and at an acceptable level of ecological performance; and c. buffer and riparian zones and other areas integral to the enhancement of the aquatic ecosystem are functioning as the intended type of ecosystem component and at an acceptable level of ecological performance. 3. The permittee shall dedicate in perpetuity by deed restriction, as a stream mitigation area, the approximately 8.25 acre mitigation area identified in the mitigation referenced in special condition 1 above. The only exceptions to the deed restriction shall be easements in existence on the date of this permit. The mitigation area shall not be disturbed, except by those activities that would not adversely affect the intended extent, condition, and function of the mitigation area. The permittee shall survey the mitigation area, develop an appropriate deed restriction for the surveyed area, submit the draft deed restriction to the USACE for review and approval, and record the USACE approved deed restriction with the County Clerk. The permittee shall provide a copy of the recorded deed restriction to the USACE by November 1, 2005. The restriction shall not be removed from the deed or modified without written approval of the USACE and conveyance of any interest in the property must be subject to the deed restriction. 4. The permittee may mow the floodplain benches within the trapezoidal channel and the adjacent 3.25 -acre riparian preservation zone, but shall limit any such mowings to: a minimum height of 10 inches, a maximum of twice per year, and during the winter dormant season from December through February. 5. The permittee shall conduct a meeting. with the construction contractor(s). detailing the terms and conditions of this permit prior to commencing construction activities of the project. The permittee shall notify the USACE of the preconstruction contractor meeting at least two weeks in advance of the meeting. Within two weeks following the meeting, the permittee shall provide written confirmation to the USACE that the meeting was held. 6. The permittee shall retain a qualified mitigation specialist (biologist, ecologist or other specialist qualified in wetland restoration, enhancement, and creation work), to oversee project construction to the extent necessary to ensure compliance with all mitigation requirements of this permit. The permittee shall have this mitigation specialist conduct all monitoring and produce any required monitoring reports. 7. The permittee shall establish and implement a self-monitoring program that includes the following actions: a. designation, in writing, of a responsible party to coordinate with the USACE concerning on-site inspections and compliance with permit conditions; b. notification to the USACE of the schedule of activities for each phase of the project at least 30 days prior to the start of soil -disturbing activities that would affect waters of the United States; and 4 c. implementation of a reporting_ program that shall include annual written compliance reports to the USACE, due October 1 for annual reporting each yea_ r, beginning in October 1, 2005. The permittee shall include in each report any schedule changes and a summary of all activities that occurred during the reporting period, including documentation_of the permittee's compliance. with the permit conditions and progress and/or completion -of -all authorized work, including mitigation activities. Each report shall address whether disturbed areas, such as borrow ditches, road embankments, stream banks, road crossings, and temporary impact areas are revegetating adequately and not suffering erosion damage. The permittee shall detail in the first report the pre -construction conditions of the project area. The permittee shall include in each report photographs, maps, and a description of the impacts to waters of the United States. Compliance reports are required even if no work is conducted during the reporting period. The permittee shall submit compliance reports until the USACE verifies that the permittee has successfully completed all compensatory mitigation plan requirements, the mitigation areas have met the standards of special condltior>i 1, and all authorized construction activities have been either completed or deleted from the project. 5 Base Map Source: USGS 7S Min. Topographical Quadrangle of Round Rock (1987) & PBugeMlle West (1987) SCALE: 1" = 2000' DRY BRANCH TRIBUTARY CHANNEL IMPROVEMENTS PROJECT LOCATION APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 1 OF 20 Base Map Source: USGS 7.5 Mtn. Topographical Quadrangle of Round Rock. TX (1987) & PflugervIlle West, TX (1987) NI Scale: 1" = 2000' PREVIOUSLY _cttfttli EgiggitAlitAj " I- • AREA NOT PREV1004„.TA17010414;Etp• APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 2 OF 20 3Nma )133?I9 Hinos • EGMENT 2 SEGMENT 1 APPLICANT:CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 3 OF 20 Q2! 100HOS S11LYO APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 0 0 m 0- 1 Z c rt d L.CO -c J LL_ (1) c W C WLZa Li O 0O•Y OCL o w. . X(22= Wz ¢o n. 0 9 . O c) ce W c Z O 8 O oN i Espey Consultants, Inc. SHEET 4 OF 20 14 C]µ o 0 0 0 N 0 -t3 to o o w n r- 0 0 n 0 (0 to t0 to 0 8 0 0 4)3 + 4) 0 4 0 O 00 0 0 - 0 0 n n n to 0 N 0 FQ 0 Z W c co = z` w. g u J U O c • 2 ;al • W ce X� �Q W 00 > F -w O v 0 1-- O. 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SO THAT THE DOWNSLOPE FACE OF THE TRENCH IS FLAT AND, PERPENDICULAR TO THE UNE OF FLOW. WHERE FENCE CANNOT • BE TRENCHED IN (E.G. 'PAVEMENT). WEIGHT FABRIC FLAP_WITH .WASHED.'GRAVEL ON UPHILL SIDE TO- PREVENT FLOW UNDER FENCE. • 4. THE TRENCH MUST BE • A -MINIMUM OF .6 INCHES DEEP • AND: 6 INCHES. WIDE TO ALLOW FOR -THE SILT FENCE FABRIC TO BE LAID IN THE GROUND ANQ. i8AC14ILLED :WITH COMPACTED. MATERIAL'. •• . . • 5. SILT EfNCE SHOULD BE SECURELY FASTENED TO EACH . STEEL SUPPORT POST OR TO WOVEN WIRE. WHICH IN :TURN . IS ATTACHED- TO THE 'STEEL FENCE: POST. 6. INSPECTION SHALL BE -MADE WEEKLY QR 'AFTER EACH . RAINFALL EVENT AND REPAIR OR REPLACEMENT .SHALL • BE - - MADE ,(PROMPTLY AS 'NEEDED. . 7. SILT FENCE SHALL BE REMOVED WHEN THE- SITE IS COMPLETELY STABILIZED SO AS NOT TO BLOCK OR IMPEDE STORM FLOW OR DRAINAGE. . 8: ACCUitULATED • SILT SHALL BE REMOVED WHEN IT REACHES A DEPTH OF 6 INCHES. THE _SILT SHALL BE DISPOSED • - OF 1N AN AI'PROVEP *SITE AND .IN SUCH A -MANNER. AS _TO "NOT CONTRIBUTE TO. ADDITIONAL SILTATION • it!J tT RtTUU: Scale: Oate oiown br 8. OZTIZ . :IL ' FENCE DETAIL APPLICANT CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 DETAIL NO. SHEET 15 OF 20 STREET R.O.W. 50' MINIMUM. TRANSITION TO ROADWAY. z GRADE TO PREVENT RUNOFF FROM LEAVING SITE. NOTES: MMritirstirT u , 1. STONE SIZE SHALL BE 3' — 5' OPEN GRADED• ROCK. 2. THICKNESS OF CRUSHED STONE PAD TO BE NOT LESS THAN 8". 3. LENGTH SHALL BE MINIMUM OF 50' FROM ACTUAL ROADWAY, MW WIDTH NOT LESS THAN FULL WIDTH OF INGRESS/EGRESS. 4, ENTRANCE SHALL BE PROPERLY GRADED TO PREVENT RUNOFF FROM LEAVING THE CONSTRUCTION SITE. THE ENTRANCE SHALL BE MAINTAINED IN A CONDITION WHICH WILL PREVENT TRACKING OR FLOWING OF SEDIMENT ONTO PUBLIC RIGHTS OF WAY. ALL SEDIMENT SPILLED. DROPPED, WASHED OR TRACKED ONTO PUBUC 'RIGHTS • OF WAY MUST BE REMOVED IMMEDIATELY BY CONTRACTOR. AS NECESSARY, WHEELS MUST BE CLEANED TO REMOVE SEDIMENT PRIOR TO ENTRANCE ONTO PUBLIC RIGHT OF WAY. WHEN WASHING IS REQUIRED, IT SHALL BE DONE ON AN AREA STABIUZED WITH CRUSHED STONE WHICH DRAINS INTO AN APPROVED SEDIMENT TRAP OR SEDIMENT BASIN. ALL SEDIMENT SHALL BE PREVENTED FROM ENTERING ANY STORM DRAIN, DITCH OR WATERCOURSE USING APPROVED METHODS. EXISTING GRADE. (Ltitt of Ruuttb ?Burk Scale: N.T.S. Orcrom by:. B. ORTIZ STABIUZED CONSTRUCTION ENTRANCE DETAIL DETAIL NO. APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 16 OF 20 4:30 Atesr • PLASM itticI+. DRIP UNE QFEXtSTfiG REE. . '.Cs..p iy,� .�• 4 m 'O: Z.- • j' APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 17 OF 20 30' VEGETATED BUFFER SHALLOW POOL N.T.S. /L30. VEGETATED BUFFER MITIGATION CHANNEL PROPOSED MITIGATION CROSS-SECTION/ SEGMENT 2 APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 18 OF 20 APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY; TEXAS - PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION. PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 19 OF 20 APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 SHEET 20 OF 20 • = 1 Attachment 1 - Dredge and Fill Certification USACE Permit No. 200200684 August 5, 2005 Page 1 of 2 WORK DESCRIPTION: As described in the public notice dated September24, 2004, and the July 7, 2005, Decision Document. SPECIAL CONDITIONS: None. GENERAL: This certification, issued pursuant to the requirements of. Title 30, Texas Administrative Code, Chapter 279, is restricted to the work described in the application or joint public notice and shall expire five years from the date of issuance of the Corps of Engineers (COE) permit. This certification may be extended to any minor revision of the COE permit when such change(s) would not result in an impact on water quality. The Texas Commission of Environmental Quality (_TCEQ1 reserves the right to require full joint public notice on a request for minor revision. The applicant is hereby placed on notice that any activity conducted pursuant to the COE permit which results in a violation of the state's surface water quality standards may result in an enforcement proceeding being initiated by the TCEQ or a successor agency. STANDARD PROVISIONS: These following provisions attach to any permit issued by the Corps of Engineers and shall be followed by the permittee or any employee, agent, contractor, or subcontractor of the permittee during any phase of work authorized by a Corps permit. 1. The water quality of wetlands shall be maintained in accordance with all applicable provisions of the Texas Surface Water Quality Standards including the General, Narrative, and Numerical Criteria. 2. The applicant shall not engage in any activity which will cause surface waters to be toxic to man, aquatic life, or terrestrial life. 3. Permittee shall employ measures to control spills of fuels, lubricants, or any other materials to prevent them: from entering a watercourse. All spills shall be promptly reported to the TCEQ, Emergency Spill Response, at (512) 463-7727. 4. Sanitary wastes shall be retained for disposal in some legal manner. Marinas and -similar operations which harbor boats equipped with marine sanitation devices shall provide state/federal permitted treatment facilities or pump out facilities for ultimate transfer to a permitted treatment facility. Additionally, marinas shall display signs in appropriate locations advising boat owners that the discharge of sewage from a marine sanitation device to waters in the state is a violation of state and federal law. 5. Materials resulting from the destruction of existing structures shall be removed from the water or areas adjacent to the water and disposed of in some legal manner. 6. A discharge shall not cause substantial and persistent changes from ambient conditions of turbidity or color. The use of silt screens or other appropriate methods is encouraged to confine suspended particulates. 7. The placement of any material in a watercourse or wetlands shall be avoided and placed there only with the approval of the Corps when no other reasonable alternative is available. If work within a wetland is unavoidable, gouging or rutting of the substrate is prohibited. Heavy equipment shall be placed on mats to protect the substrate from gouging and rutting if necessary. 8. Dredged Material Placement: Dredged sediments shall be placed in such a manner as to prevent any sediment runoff onto any adjacent property not owned by the applicant. Liquid runoff from the disposal area shall be retained on-site or shall be filtered and retumed to the watercourse from which the dredged materials were removed. Except for material placement authorized by this permit, sediments from the project shall be placed in such a manner as to prevent any sediment runoff into waters in the state, including wetlands. .At`achment 1 - Dredge and Fill Certification USACE Permit No. 20G200684 August 5, 2005 Page 2 of.2 9 If contaminated spoil that was not anticipated or provided for in the permit application is encountered - during dredging, dredging operations shall be immediately terminated and the TCEQ, Emergency Spill Response, shall be contacted at (512) 463-7727. Dredging activities shall not be resumed until authorized by the Commission. 10. Contaminated water, soil, or any other material shall not be allowed to enter 'a watercourse. Noncontaminated storm water from impervious surfaces shall be controlled to prevent the washing of debris into the waterway. 11. Storm water runoff from construction activities that result in a disturbance of one or more acres, or are a part of a common plan of development that will result in the disturbance of one or more acres, must be controlled and authorized under Texas Pollutant Discharge Elimination System (TPDES) general permit TXR150000. A copy of the general permit, application (notice of intent), and additional information is available at: http://www.tnrcc.state.tx.us/permitting/waterperm/wwperm/construct.html or by contacting the TCEQ Storm Water & Pretreatment Team at (512) 239-4433. 12. Upon completion of earthwork operations, all temporary fills shall be removed from the watercourse/wetland, and areas disturbed during construction shall be seeded, riprapped, or given some other type of protection to minimize subsequent soil erosion. Any fill material shall be dean and of such composition that it will not adversely affect the biological, chemical, or physical properties of the receiving waters. 13. Disturbance to vegetation will be limited to only what is absolutely necessary. After construction, all disturbed areas will be revegetated to approximate the pre -disturbance native plant assemblage. 14. Where the control of weeds, insects, and other undesirable species is deemed necessary by the permittee, control methods -which -are nontoxic to aquatic life or human health shall be employed when the activity is located in or in close proximity to water, including wetlands. 15. - Concentrations of taste and odor producing substances shall not interfere with the production of potable water by reasonable water treatment methods, impart unpalatable flavor to food fish including shellfish, result in offensive odors arising from the water, or otherwise interfere with reasonable use of the water in the state. 16. Surface water shall be essentially free of floating debris and suspended solids that are conducive to producing adverse responses in aquatic organisms, putrescible sludge deposits, or sediment layers which adversely affect benthic biota or any lawful uses. 17. Surface waters shall be essentially free of settleable solids conducive to changes in flow characteristics of stream channels or the untimely filling of reservoirs, lakes, and bays. 18. The work of the applicant shall be conducted such that surface waters are maintained in an aesthetically attractive condition and foaming or frothing of a persistent nature is avoided. Surface waters shall be maintained so that oil, grease, or related residue will not produce a visible film of oil or globules of grease on the surface or coat the banks or bottoms of the watercourse. 19. This certification shall not be deemed as fulfilling the applicant's/permittee's responsibility to obtain additional authorization/approval from other local, state, or federal regulatory agencies having special/specific authority to preserve and/or protect resources within the area where the work will occur. EXHIBIT C Mitigation Plan PROJECT MITIGATION PLAN FOR DRY BRANCH TRIBUTARY CHANNEL IMPROVEMENT PROJECT CITY OF ROUND ROCK WILLIAMSON COUNTY, TEXAS. USACE PROJECT NO: 200200684 Revised May 2005 Project Mitigation Plan BASELINE INFORMATION The City of Round Rock proposes to construct channel modifications for a Dry Branch tributary to correct problems of bed scour and bank stability, as -well as to address concerns of public safety associated with flooding. All practicable options for avoidance, minimization, and mitigation of impacts to wetlands were exercised during design of the proposed project. The proposed project includes deeper excavation into the native bedrock and soil substrate, which would form the bottom of the improved channel. Side slopes (outside of the channel width) would be reinforced with stone where necessary. This excavation would continue downstream to the tributary's intersection with Dry Branch. Minor bank stabilization activities are proposed within a portion of a previously channelized section of the Dry Branch tributary between Gattis School Road and the --section _to be.deepened _(see Sheets 3 and 4 of 20 in permit application). This alternative would increase capacity while utilizing a "self -mitigating" approach. This self -mitigating approach will be accomplished by excavating a meander channel with an integral riffle/pool segment sequence to enhance stream function accompanied by tree plantings adjacent to Segment 2. The channel design would include a back -slope swale designed to encourage drainage of the overflow areas following a bankfull storm event, as well as a re- formed soil bed exhibiting herbaceous plants. The project would impact one water of the U.S. (an unnamed tributary to Dry Branch) both permanently and temporarily. No wetlands will be impacted. A total of 2.24 acres of waters of the U.S. would be impacted. Compensation for unavoidable permanent and temporary impacts will be accomplished through use of a self -mitigating channel design, riparian plantings adjacent to the channel, and creation of_ a Riparian Preservation Zone (RPZ) along a neighboring creek in the Brushy Creek watershed.. (1) Avoidance and Minimization - Avoidance and minimization measures have been considered for this project to the maximum extent practicable during the planning and design phases for this project. The no -build alternative was . considered. but - eliminated early on . in_ the ...process_as it would not _ meet the_ __. purpose and need of correcting existing problems of bed scour and bank stability, or address concerns of public safety associated with flooding. City of Round Rock --Dry Branch Tributary Improvements) USAGE Project # 200200684 May 2005 . Project Mitigation Plan Four alternatives, including the no -build alternative were studied. After study of the alternatives, the preferred was selected based primarily on the need to correct existing problems of bed scour and bank stability, and address concerns of public safety associated with flooding. Originally an alternative was investigated which consisted of simply deepening the existing channel and using a "traditional" trapezoidal design for the deepened channel. While practicable this alternative did not address stream dynamics issues and was ultimately abandoned. Another previous alternative included a proposal to line a portion of the channel with concrete. Following an April 4, 2003, field visit, the USACE—Fort Worth District office provided feedback indicating that this would result in numerous concerns from the regulatory community and was not advisable. Based on this correspondence, the project design was revised to remove the concrete component from the proposed action. The recommended preferred alternative is described in greater detail in this permit application and mitigation plan. (2) Impacts Direct permanent impacts will consist of the deepening of existing jurisdictional channels and the placement of earthen fill in jurisdictional areas. Temporary impacts will consist of vegetation removal and earth moving in jurisdictional areas that will be restored once construction is completed. The portions of the existing channel (Segment 2) for Dry Branch Tributary within the limits of the proposed channel will be completely excavated and will cease to be an unaltered natural drainage. The tributary will follow the path of the proposed channel that connects previous channel improvements upstream (Segment 3) and downstream (Segment 1). The approximately 112 to 156 foot wide proposed channel (top width) is designed to contain the 100 -yr flood,. preempting damage to future residences adjacent to the channel (see Sheet 13 of 20). Portions of the existing channel outside the limits of the proposed channel will be completely filled, regraded and revegetated as necessary. The proposed channel will connect with the previously improved 80 -foot wide (bottom width) earthen channel upstream and the primary Dry Branch channel downstream. This ultimate channel is designed to contain the fully developed 100 -yr flow rate along the entire length of Dry Branch Tributary from its headwaters to its confluence with Dry Branch. City of Round Rock --Dry Branch Tributary Improvements2 USACE Project # 200200684 May 2005 Project Mitigation Plan (3) Plan Goals and Objectives The goals and objectives for this mitigation plan are to appropriately compensate for impacts to jurisdictional areas that_ cannot be avoided or further minimized in the construction of this project. Compensation for unavoidable impacts will be accomplished through a self -mitigating on-site design coupled with additional plantings and protection of a Riparian Protection Zone, as described in this report. (4) Proposed Mitigation Area See Wetland Delineation Report, submitted under separate cover. (5). Jurisdictional Determination See Wetland Delineation Report, submitted under separate cover. (6) Proposed Compensatory Mitigation This project is proposed to be partially self -mitigating. The City proposes to excavate a low flow mitigation channel within Segments 1 and 2, intended to replace some of the lost function and habitat (see Sheet 18 of 20). The proposed low flow channel is approximately 1 foot in depth, includes a sinuous meander and a bottom width of 20 feet with cross slopes of 1% to 2%. The meandering low flow channel includes a series of steep slopes (0.6%) and flat slopes (0%) to encourage a "riffling and pooling" sequence throughout the improvement reach. The downstream end of the "pool" reach includes rock boulders to restrict flow and provide habitat cover. Velocities at low flows (50 to 120 -cubic feet per- second, cfs) range from 3 to 6 feet per second (fps). These velocities will encourage the transport- of sediment through the system.. and discourage the collection of sediment that may adversely affect conveyance of the channel. The inside bend of the meandering low flow channel includes a "point bar," or "single" floodplain bench (the bottom of the main channel) that will be frequently inundated. The interior side of the bench includes an `.`.overflow" channel, that will drain the floodplain bench once floodwaters have receded. The area between the overflow channel and the low flow channel will include a soil bed with a topsoil layer taken from deposits located throughout the existing channel to maintain the existing plant/grass species that have been established. A temporary mat will be required to reinforce the topsoil until vegetation has been established. This area will encourage the uptake of nutrients City of Round Rock --Dry Branch Tributary lmprovements3 USAGE Project # 200200684 May 2005 Project Mitigation Plan adding a water quality benefit to the system. The bankfull condition would be contained within the rock wall protection at the edges of the channel. The meandering channel would, retain the integrity of the existing stream to the extent possible,. would include riffles and pools where practicable and feasible, and would still maintain the proposed function of the project itself, which is adequate conveyance of storm water. (7) Existing Liens and Encumbrances All property is owned or controlled by the City of Round Rock. (8) Protective Actions Erosion and sedimentation control measures, site work and restoration work shall be in accordance with the City of Round Rock Erosion and Sedimentation Control Ordinance (see Sheets 14 through 17 of 20). All slopes shall be sodded or seeded with approved grass, grass mixtures, or ground cover suitable to the area and season in which they are applied (see table below for proposed seed mix). Silt fences, rock berms, sediment basins or similarly recognized techniques and materials shall be employed during construction to prevent point- source sedimentation loading of downstream facilities. Proposed Erosion Control Seed Mix Common Name Plant Type Scientific Name Application rate (lbs/1000 ft2) Buffalograss Grass Buchloe dactyloides 0.3 _ Green Sprangletop Grass Leptochloa dubia 0.4 Yellow Indiangrass Grass Sorghastrum nutans 0.2 Little Bluestein Grass Schizachyrium scoparium 0.2 Canada Wildrye Grass Elymus canadensis 0.2 Purple Threeawn Grass Aristida purpurea 1.2 Sideoats Grama Grass Bouteloua curtipendula 1.3 Texas Bluebonnet - Wildflower- - ------ - Lupinus texensis - - 1.4 Purple Prairie Clover Wildflower Petalostemum purpurea 0.1 Plains Coreopsis Wildflower Coreopsis tinctoria 0.05 Goldenrod Wildflower Solidago altissima -0.02 Greenthread Wildflower Thelesperma filifolium 0.075 City of Round Rock --Dry Branch Tributary Improvements USACE Project # 200200684 May 2005 Project Mitigation Plan Common Name Plant Type Scientific Name Application rate (lbs/1000 ft2) Indian Blanket Wildflower Gaillardia pulchella 0.15 Lemon Mint Wildflower Monarda citriodora .: 0.06 .... Mexican Hat Wildflower Ratibida columnifera 0.05 Pink Evening Primrose Wildflower Oenothera speciosa 0.02 Annual Sunflower Wildflower Helianthus annuus 0.075 (9) Hydrologic Information All construction is along the bottom and side slopes of the excavated floodway. (10) Mitigation Area Substrate The area between the overflow channel and the low flow channel will include a soil bed with a topsoil layer taken from deposits located throughout the existing channel to maintain the existing plant/grass species that have been established. A temporary mat will be required to reinforce the topsoil until vegetation has been established. This area will encourage the uptake of nutrients adding a water quality benefit to the system. (11) Planting Plan Stream Channel Mitigation Measures The meandering channel would retain the integrity of the existing stream to the extent possible, would include riffles and pools where practicable and feasible, and would still maintain the _ proposed function of the project itself, which is adequate conveyance of storm water. In addition to the replacement of stream function, an attempt would be made to replace the lost riparian vegetation and habitat within a 30 -foot vegetated buffer (see Figures 1-3) along both sides of the proposed channel adjacent to Segment 2 (totaling approximately 5.5 acres). The 30 -foot buffer would be populated with native trees and plants in accordance with the attached species list (a subset of the City's List of Approved Trees for Round Rock). The vegetated buffer would be designed and planted with a target survival rate of 50% and a target density of approximately 160. - trees per acre. Plantings would consist of bare root or potted seedlings as available and would be planted by hand. City of Round Rock --Dry Branch Tributary Improvements5 USACE Project # 200200684 . May 2005 Project Mitigation Plan Additionally, the City proposes to stockpile the seed bank/topsoil from the areas to be excavated for the proposed project and use this seed bank to reseed portions of the bed of the channel. This will be accomplished by stockpiling approximately the surface four inches of the excavated areas which contain desirable species, excluding those areas containing cattails or other undesirable species, and replacing this topsoil in portions of the channel bed after construction. - Additional Riparian Woodland Plantings In addition to the self -mitigating nature of the channel design as described above the City proposes planting trees in several areas adjacent to the proposed project. Three areas where additional riparian tree plantings are proposed are indicated in the drawings on Figure 3. These areas total approximately 3.26 acres. The City also proposes to plant a line of trees on the side slopes along both sides of the stream in Segments 1 and 3. The planted trees would be staggered and planted at an approximately 15 -foot spacing, on center. Trees planted in all these areas would be native species in accordance with the attached list (a subset of the City's List of Approved Trees for Round Rock). Establishment of Riparian Preservation Zone (RPZ) In response to resource agency comments, the City proposes to create a.high-quality Riparian Preservation Zone (RPZ) as additional compensatory mitigation for project -related impacts. The RPZ consists of approximately 8.25 acres (1,550 linear feet) on both sides of Lake Creek approximately mile north of the Dry Branch tributary (see Figure 4). Lake Creek within the RPZ has an ordinary high water mark of approximately 25 feet. The perennial creek lies within a riparian corridor approximately 150 to 200 feet wide. The streambed is between bluff banks approximately 30 feet lower than the top of the banks. It is presently wooded with a canopy cover of approximately 80%. Dominant canopy species are live oak (Quercus virginiana), cedar elm (Ulmus crassifolia), Ashe juniper (Juniperus asheii), pecan (Carya illinoensis), Osage orange (Madura pomifera), and black willow (Salix nigra). Diameters at breast height (dbh) range from 6 to 40 inches and average approximately 10 inches while heights range, from 15 to 45 feet and average approximately 30 feet. The shrub/sapling layer is dominated by canopy species saplings, red buckeye (Aesculus pavia) and deciduous holly (Ilex decidua). Common vines include greenbrier (Smilax sp.), Japanese honeysuckle (Lonicera japonica), and poison ivy (Toxicodendron radicans). Dominant herbaceous species include Canada wildrye (Elymus _canadensrs), Johnson grass (Sorghum, halepense), and curly dock (Rumex crispus). A hike and bike trail will be constructed in this area outside the 100 -year floodplain. Otherwise the area will be preserved as it is now, with considerations for periodic maintenance. Photographs of the area are attached at the end of this plan. City of Round Rock --Dry Branch Tributary Improvements6 USACE Project # 200200684 May 2005 Project Mitigation Plan (12) Planting Success Criteria Herbaceous Communities The City proposes a goal of 80% ground cover in thefloodplain bench soilbed after 3 years. To ensure reaching these goals the soil bed will be monitored with a monitoring report to be submitted to the U.S. Army Corps of Engineers — Fort Worth District annually for 3 years (beginning in the year construction is completed). These reports will be submitted to the Corps by October 1 each year. If these plantings do not meet the goals stated above supplemental plantings will be performed. In addition, the erosion control and bank stabilization measures proposed within Segment 3 comprise a beneficial enhancement to the aquatic environment. Woody Communities An attempt would be madeto_. replace the lost_ riparian vegetation and habitat within a 30 -foot vegetated buffer along both sides of the proposed channel adjacent to Segment 2 (totaling approximately 5.5 acres). The 30 -foot buffer (see Figures 1-3) would be populated with native trees and plants in accordance with the attached species list (a subset of the City's List of Approved Trees for Round Rock). Three areas where additional riparian tree plantings are proposed are indicated on Figure 3. These areas total approximately 3.26 acres. The woody species plantings would be designed and planted with a target survival rate of 50% and a target density of approximately 160 trees per acre. No single species would constitute more than 30% of the surviving plantings. The City also proposes to plant a line of trees on the side slopes along both sides of the stream in Segments 1 and 3. The planted trees would be staggered and planted at an approximately 15 - foot spacing, on center. Trees would be native species would be from the City's list of Medium Trees, and would be replaced if mortality exceeds 15%. Maintenance The City will mechanically mow accessible portions of the channel side -slopes and vegetated areas within the channel on a yearly basis in order to remove any impediments to conveyance, such as woody species (other than planted trees/shrubs). In addition, undesirable invasive species and woody species not accessible to mowers will be manually treated with appropriate herbicides. in order tominimize the occurrence of these species. (13) Performance Standards The permittee will maintain the mitigation area so that the water of the U.S. is functioning at the City of Round Rock—Dry Branch Tributary Improvements? USACE Project # 200200684 May 2005 Project Mitigation Plan level of ecological performance described in (11) to ensure that: • Waters of the U.S. are functioning as the intended type of waters of the U.S. and at the level of ecological performance prescribed in the mitigation plan. • Buffer and riparian zones and other areas integral to the enhancement of the aquatic ecosystem are functioning as the intended type of ecosystem component and at the level of ecological performance prescribed in the mitigation plan. (14) Ecological Benefits The mitigation plan as proposed would create a more diverse habitat in the portions of the project area that are already channelized while lessening erosion from flood events. (15) Threatened and Endangered Species A search of the map repository of sensitive species and community types maintained by the Natural Diversity Database (NDD) at the Texas Parks and Wildlife Department (TPWD) was performed in February 2004 to encompass the project area. No known endangered, threatened, or otherwise rare or sensitive plant species, animal species or community type occurrences_ have. been reported within or immediately adjacent to the impact area. No habitat for listed species occurs on the site. No impacts are anticipated. (16) Additional Relevant Information A cultural resource investigation found no archeological sites or Section 106 issues (letter from THC provided to USACE in original permit submittal). No significant ecologically sensitive areas occur within the project's area of potential effect. Construction of the proposed channel, as proposed, would minimize impacts to regional hydrology. (17) Operation and Management Plan Once success criteria for the mitigation areas (soil bed and woody plantings) are met these sites will be maintained in perpetuity. The portions of the project area where woody species are not planted will be mowed by the City twice a year. All structures will be maintained by the City. City of Round Rock --Dry Branch Tributary Improvements8 USACE Project # 200200684 May 2005 Project Mitigation Plan (18) Monitoring Plan Mitigation progress shall be measured in two ways: (a). Vegetative enhancements will be monitored. as outlined in (11) and (12), above; and (b). Proposed channel features as described in this document will be monitored and documented in the yearly reports outlined in (19), below. Contingency Plan Compensatory over planting of desirable species is designed to lessen the probability that success criteria are not met. In the event that success criteria for this mitigation plan are not met steps will be taken to ensure that they are met in the future (replanting, etc.). (19) Reporting Plan An annual report will be submitted to the USACE by the City on or before the first of October detailing the status of the mitigation plan and activities taking place in the preceding year. This annual report will be submitted for a minimum of three consecutive years, beginning in the year construction takes place. (20) Mitigation Specialist The City of Round Rock will contract with or employ a qualified mitigation specialist to oversee implementation of this plan. (21) Schedule Construction is scheduled to begin in early 2005 (originally scheduled for 2004). Project mitigation will occur contemporaneous with construction of the channel modifications and plantings are expected to be completed by. March 2007. It is anticipated that construction will be completed in mid- to late- 2005, with the first of three monitoring reports submitted by October 1, 2005. (22) Provision for a Protective Covenant The property will remain in City of Round Rock ownership/control in perpetuity. The Riparian Preservation Zone (RPZ) shown in Figure 4 will be protected by deed restriction, with stipulations made for long-term maintenance and future construction of a hike and bike trail. City of Round Rock --Dry Branch Tributary Improvements9 USACE Project # 200200684 May 2005 GREENSLOPES AT LAKE CREEK EXISTING UPSTREAM CHANNEL IMPROVEMENT Base Map Source: USGS 7.5 Mni: Topographical Quadrangle of Round Rock, TX (1987) & Pfiugervilie West, TX (1987) Scale: 1' = 2000' PREVIOUSLY CHANNELIZED AREA AREA NOT PREVIOUSLY CHANNELIZED APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: MAY 2005 MITIGATION PLAN FIGURE 1 30' VEGETATED BUFFER SHALLOW POOL N.T.S. MITIGATION CHANNEL 30' VEGETATED BUFFER_. PROPOSED MITIGATION CROSS-SECTION / SEGMENT 2 APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: MAY 2005 MITIGATION PLAN FIGURE 2 =_ _ 4 { iv a 0� . �0�/M . . = J Ir RO�C�yC 010- \O, 441 \ -- _ 30 FOOT BUFFER AREA Mike0S4 TRAif APPLICANT CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: MAY 2005 PLANTING AREAS MITIGATION PLAN FIGURE 3---_: APPLICANT: CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: MAY 2005 RIPARIAN PROTECTION ZONE MITIGATION PLAN FIGURE 4 LIST OF APPROVED NATIVE TREES FOR ROUND ROCK Common Name Scientific Name Large Trees (mature height 40 feet or more) Bur Oak Quercus macrocarpa Live Oak Quercus virginiana Chinquapin Oak Quercus muehlenbergii Shumard Red Oak Quercus shumardii Cedar Elm Ulmus crassifolia Pecan Carya illinoensis Bald Cypress Taxodium distichum Montezuma Cypress Taxodium mucronatum Eastern Black Walnut Juglans nigra Southern Magnolia Magnolia grandiflora Post Oak Quercus stellata American Elm Ulmus americana Medium Trees (mature height 25-40 feet) Texas (Spanish) Red Oak Lacey Oak Texas Ash Mesquite Western Soapberry Escarpment Black Cherry Bigtooth Maple Carolina Cherry Laurel Texas (Little) Walnut Eastern Red Cedar Quercus buckleyi Quercus laceyi Fraxinus texensis Prosopis glandulosa Sapindus drummondii Prunus serotina ssp. Eximia Acer grandidentatum Prunus caroliniana Juglans macrocarpa Juniperus virginiana Small Trees (mature height 8-25 feet) Texas Redbud Mexican Plum Mountain Laurel Mexican Buckeye Yaupon Holly Texas Persimmon Vitex Desert Willow Possumhaw Holly Carolina Buckthorn Eve's Necklace American Smoke Tree Blanco Crab Apple Flameleaf Sumac Texas Pistache Wax Myrtle Texas Madrone Rough -leaf Dogwood Cercis canadensis Prunus mexicana Sophora secundora Ungnadia speciosa Ilex vomitoria Diospyros texana Vitex spp. Chilopsis linearis Ilex decidua Rhamnus caroliniana Sophora affinis Cotinus obovatus Pyrus ioensis Rhus copallina Pistacia texana Myrica cerifera Arbutus xalapensis Cornus drummondii 1. kW. Grimes bridge over Lake Creek. 2. Lake Creek from top of bluff on south side. PAGE 1 OF 3 3. Large pooled area of Lake Creek. 4. Looking northwest from creek bank up slope through riparian area of Lake Creek. PAGE 2 OF 3 5. Lake Creek, looking downstream. 6. Lake Creek, looking upstream. PAGE 3 OF 3 EXHIBIT D Dry Branch Project (DR Horton and CoRR Responsible Portions of the Project) • 1j 11111 VI{ :-I .m -Atm o�Z.Zra mal551 lifiaz VII 42 221 2= Cri\VAZ ram u: 421 ZS 2: RlJla`(rn St/N{n{{{7♦6 j n{{{{{nn{n � �i Wise �{mnnnnnn.' ,to aC En z0 b. Boa menu{ —tramit. p� ® �e ::!'!:.s aMiitiaZ II Ike= 11111111111111114�• 0.1111111111114. rt-vt,-.44%.1111111 11111111{ gumming-figf �r* 11 4 1 11►O1 -An►an6„ EXHIBIT E Performance Bond from D.R. Horton EXHIBIT F Riparian Tree Plantings cu ("No 0- "o 441. 30 FOOT BUFFER AREA 4 1,1 0 U 0 4 Q Q MiM054 TRAIL PLANTING AREAS APPLICANT: PROJECT: D PROJECT #: DATE: APRIL CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS RY BRANCH TRIBUTARY CHANNELIZATION 200200684 2005 MITIGATION PLAN FIGURE 3" EXHIBIT G Riparian Protection Zone APPLICANT CITY OF ROUND ROCK, WILLIAMSON COUNTY, TEXAS PROJECT: DRY BRANCH TRIBUTARY CHANNELIZATION PROJECT #: 200200684 DATE: FEBRUARY 2005 RIPARIAN PROTECTION ZONE SHEET 19 OF 20