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R-79-226 - 7/12/1979WHEREAS, Haynie & Kallman, Inc. has submitted a letter of agreement to begin the preparation of plans and specifications as detailed in the Preliminary Engineering Report which was com- pleted in January, 1979, and WHEREAS, the City Council wishes to enter into this letter agreement with Haynie & Kallman, Inc., Now Therefore BE _IT RESOLVED BY THE COUNCIL OF THE CITY OF ROUND ROCK, TEXAS, THAT The mayor of the City of Round Rock, Texas, is hereby authorized and directed to execute on behalf of the City, an'agree- ment with Haynie & Kallman, Inc., a copy of such agreement being attached hereto and incorporated herein for all purposes. RESOLVED this /a, 'day of _ AAA _ 1979. AO LIFe L. "I" N, ayor City of Round Rock, Texas E LAND, Y Y WHEREAS, the City Council wishes to proceed with the de- sign phase of the North Fork Reservoir Water Supply Improvements, and ATTEST: -- RESOLUTION NO. p� : R JOA Cit Secretar d Haynie & Kaltman, Inc. CONSULTING ENGINEERS 2115 North Mays Round Rock, Texas 78664 (512) 255 -4564, 255 -7861 Mr. Bob Bennett, City Manager City of Round Rock 214 East Main Street Round Rock, Texas 78664 Dear Mr. Bennett: Upon your request, we are pleased to submit this letter for authorization to proceed on the Design Phase of the North Fork Reservoir Water Supply Improvements for preparation of plans and specifications as detailed in the previously completed January, 1979 Preliminary Engineering Report. The - proposed improvements would include a water treatment plant, 30" water trans- mission line and associated appurtenances for delivering treated water to the City of Round Rock service area. Charges for these engineering services as described herein were agreed to in the September 14, 1978 authorization for the Preliminary Engineering Report and are shown again with an excerpt as follows: "Charges for engineering services as described herein will be classified on the appropriate curves as included in our August 19, 1977 contract with the City of Round Rock (1977 Capital Improvements Program). Such contract shall become an attachment hereto and a part of this Agreement, with exceptions to Section VI - The Engineer's Compensation as shown herein. SECTION VI - THE ENGINEER'S COMPENSATION The total compensation for work completed shall be determined and payable as follows: Design 85% of basic charge less $10,000 payment made in preliminary phase Construction 15% of basic charge July 9, 1979 Upon the owner's acceptance of plans & specifications within 30 days after submission. Monthly in proportion to the construction work completed." Timothy E. Haynie, P.E. Steven D. Kaltman, P.E. RE: Authorization to proceed on Design Phase of North Fork Reservoir Water Supply Improvements CIVIL ENGINEERING • LAND PLANNING • MUNICIPAL CONSULTANTS • SURVEYING Mr. Bennett, City Manager July 9, 1979 Page Two The estimated cost of Design Phase services would be 85% of the estimated basic charge of $370,650 (See Preliminary Engineering Report, Page 46) less $10,000 payment made for the Preliminary Engineering Report which is an estimated amount of $305,000. This amount would be due within 3 to 4 months from the date of this authorization letter, when the Design Phase (plans and specifications) is completed. We recommend an additional amount of $10,000 be budgeted for easements and other miscellaneous services. Please sign both copies in the spaces provided below authorizing this Agreement for us to proceed on the Design Phase if it meets with your approval and return one copy to our office. Please retain one executed copy for your files. We appreciate the opportunity to be of continuing service to the City of Round Rock. SK:kmm t Cordially, HAYNIE & KALLMAN, INC. Steve Kallman, P.E. 1 1 1 1 1 aok, 1 1 1 1 1 1 1 1 1 1 1 1 Haynie & Kaltman Inc. CONSULTING ENGINEERS 2115 North Mays Round Rock, Texas 78664 (512) 255-4564 Mr. Bennett, City Manager July 9, 1979 Page Two The estimated cost of Design Phase services would be 85% of the estimated basic charge of $370,650 (See Preliminary Engineering Report, Page 46) less $10,000 payment made for the Preliminary Engineering Report which is an estimated amount of $305,000. This amount would be due within 3 to 4 months from the date of this authorization letter, when the Design Phase (plans and specifications) is completed. We recommend an additional amount of $10,000 be budgeted for easements and other miscellaneous services. Please sign both copies in the spaces provided below authorizing this Agreement for us to proceed on the Design Phase if it meets with your approval and return one copy to our office. Please retain one executed copy for your files. We appreciate the opportunity to be of continuing service to the City of Round Rock. SK:kmm Cordially, HAYNIE & KALLMAN,;INC. e Steve Kaltman, P.E. Haynie & Kaltman, Inc. CONSULTING ENGINEERS 2115 North Mays Round Rock , Texas 78664 (512) 255 -4564, 255 -7861 Mr. Bob Bennett, City Manager City of Round Rock 214 East Main Street Round Rock, Texas 78664 Dear Mr. Bennett: Construction 15% of basic charge July 9, 1979 RE: Authorization to proceed on Design Phase of North Fork Reservoir Water Supply Improvements Upon your request, we are pleased to submit this letter for authorization to proceed on the Design Phase of the North Fork Reservoir Water Supply Improvements for preparation of plans and specifications as detailed in the previously completed January, 1979 Preliminary Engineering Report. The proposed improvements would include a water treatment plant, 30" water trans- mission line and associated appurtenances for delivering treated water to the City of Round Rock service area. Charges for these engineering services as described herein were agreed to in the September 14, 1978 authorization for the Preliminary Engineering Report and are shown again with an excerpt as follows: "Charges for engineering services as described herein will be classified on the appropriate curves as included in our August 19, 1977 contract with the City of Round Rock (1977 Capital Improvements Program). Such contract shall become an attachment hereto and a part of this Agreement, with exceptions to Section VI - The Engineer's Compensation as shown herein. SECTION VI - THE ENGINEER'S COMPENSATION The total compensation for work completed shall be determined and payable as follows: Design 85% of basic charge less $10,000 payment made in preliminary phase Upon the owner's acceptance of plans & specifications within 30 days after submission. Monthly in proportion to the construction work completed." CIVIL ENGINEERING • LAND PLANNING • MUNICIPAL CONSULTANTS • SURVEYING Timothy E. Haynie, P.E. Steven D. Kaltman, P.E. PRELIMINARY ENGINEERING REPORT NORTH FORK RESERVOIR TREATMENT AND TRANSMISSION FACILITIES CITY OF ROUND ROCK, TEXAS @ � TIMITHY E. HFIYNI •ta% 36982 � ry� . r �,s �t ti $' a January, 1979 Haynie & Kallman Inc. CONSULTING ENGINEERS 2115 North Mays Round Rock , Texas 76664 (512) 255 -4564, 255 -5955 TABLE OF CONTENTS TITLE PAGE SECTION I - INTRODUCTION TO PROJECT 1 SECTION II - CONCLUSIONS AND RECOMMENDATIONS 3 SECTION III - EXISTING WATER SUPPLY SYSTEM 7 SECTION IV - WATER SUPPLY REQUIREMENTS 10 SECTION V - WATER SUPPLY SOURCES 12 SECTION VI - PROPOSED FACILITIES 18 SECTION VII - BASIS OF DESIGN 30 SECTION VIII - PRELIMINARY COST ESTIMATES 45 SECTION IX - FEASIBILITY 48 SECTION X - LIST OF EXHIBITS 50 LIST OF TABLES NO. 1 - EXISTING WATER WELLS NO. 2 - POPULATION PROJECTIONS NO. 3 - WATER SUPPLY REQUIREMENTS (1979 - 1983) NO. 4 - SURFACE WATER SUPPLY REQUIREMENTS (1979 - 1988) NO. 5 - PRELIMINARY COST ESTIMATE SECTION I - INTRODUCTION TO PROJECT The City of Round Rock has recently experienced several periods of water shortage which have resulted, in the rationing of water and the suspension of building permits for new construction. These periods of temporary water shortage were the direct result of the combined effects of the City's absolute dependence on the pumpage of ground water from the Edwards Aquifer as its sole source of water supply, the lowering of the Aquifer level due to an extended period of drought and heavy pumpage, and the ever increasing demands for more water placed on the City's water system by a rapidly increasing service population. This Report was prepared in response to this water supply dilemma which has faced the City of Round Rock in the past and will undoubtedly continue to do so in ever increasing proportions in the future. An attempt has been made to quantify the City's water supply needs in the near future through service population and demand forecasting, determine the amount of water supply needed to augment the existing ground water supply capabilities, and to recommend feasible alterna- tives for meeting these increased water supply demands in the near future. The objective of this Report is to demonstrate effectively how the increased water supply needs of the City of Round Rock can be met by utilizing the North Fork Reservoir on the San Gabriel River as a surface water supply source. Justification of the source selection, water transportation mode, and design considerations for the project are presented along with cost estimates and financing alternatives for obtaining surface water from the North Fork Reservoir. 1 Based on all of this, conclusions and recommendations covering the utilization of the North Fork Reservoir as a surface water supply source for the City of Round Rock are set forth in this Report. 2 SECTION II - CONCLUSIONS AND RECOMMENDATIONS Based on the information and data presented in this report, the following conclusions and recommendations are offered concerning the North Fork Reservoir surface water treatment and transmission facilities for the City of Round Rock. A. Conclusions 1. The City of Round Rock's assumed existing ground water pumping capability of approximately 7.2 MGD (5,000 GPM), which is based on the existence of normal recharge conditions for the Edwards Aquifer, is only sufficient to meet peak water demands imposed on the system throughout the City's service area through the year 1980. This imposes a period of less than two (2) years in which the City must begin to supplement its existing ground water supply capability. In addition, based on service population and demand projections developed for the City's water service area, Round Rock will need to double its water supply capacity within five (5) years and an additional 18 MGD water supply will be needed between now and 1988, a period of nine (9) years. 2. Data concerning the ground water supply capability of the Edwards Aquifer combined with recent experience by the City during drought periods clearly indicates that it is unwise to rely on the Aquifer for any additional ground water supply in sufficient quantity to meet the City's rapidly increasing water demands in the future. Based on this, surface water represents the only available alternate source of water supply for the City of Round Rock. 3. Based on a review of all the available sources of surface water in this area, i.e. the North Fork Reservoir, Granger Lake, and Lake 3 Travis, the North Fork Reservoir represents the best alternative. This conclusion is based on the existence of a Water Supply Contract with the Brazos River Authority and a Contractual Permit issued by the Texas Water Commission for utilizing the North Fork Reservoir as a surface water supply source for the City of Round Rock. In addition, the North Fork Reservoir is closer than either Granger Lake or Lake Travis and, therefore, it should be more economical to obtain water from it. It is noted that due to the uncertainty surrounding the construction of the South Fork Reservoir at some unspecified time in the future, this Reservoir is not considered an available source of surface water at the present time. 4. All of the proposed facilities required for obtaining, treating, and transporting surface water from the North Fork Reservoir to the City of Round Rock should be constructed in phases as pro- posed up to the ultimate system design capacity of 18 MGD for the following reasons; a. Phase 1 of the treated water transmission line extending from the North Fork Reservoir to the existing 750,000 gallon Business Highway 81 North Standpipe will have a design capacity of 3.0 MGD and provide a complete link between the two points. The future design capacity increases up to 6.0 MGD (phase 2) and 18 MGD (phase 3) will require the paralleling of existing lines which are utilized to the extent possible in phase 1 only if the new portions of the waterline proposed under phase 1 are initially constructed with the 18 MGD design capacity instead of a smaller capacity. In addition, the overall cost of the waterline would be substantially less if the necessary new 4 portions of the phase 1 line were sized for 18 MGD which would then require only the additions of lines parallel to the previously existing lines utilized in phase 1 to raise the overall capacity up to 18 MGD. b. Phasing of the construction of the raw water intake structure, the water treatment plant, and the booster pump station would allow a lower initial cost for each of these facilities and provide for the expansion of each to match the increases in demand for water. This would avoid the needless waste of available construction funds and inefficient operation of a facility initially experiencing significantly less demand than it is designed for. 5. The proposed routing of the treated water transmission line from the North Fork Reservoir to the City of Round Rock makes the most efficient use of existing facilities such as the 18 -inch waterline crossing under IH 35 at Rabbit Hill Road (Westinghouse Road) and the 12 -inch waterline extending north along IH 35 to Chandler Road from the existing 750,000 gallon Business Highway 81 North Standpipe. In addition, it utilizes existing property lines and right -of -ways to the extent possible and avoids crossing open land tracts or areas of existing development to simplify the necessary easement acquisitions for the waterline. 6. The possibility exists for the joint -use of the existing fixed intake structure and raw water transmission line constructed by the City of Georgetown at the North Fork Reservoir. Joint -use of these facilities would necessitate locating the water treatment plant along the northern shore of the North Fork Reservoir and 5 approximately 3,600 additional feet of treated water transmission line ($200,000) than if Round Rock constructed its own facilities along the southern shoreline of the Reservoir. Due to the design capacity of the existing facilities constructed by Georgetown, Round Rock would need all of their capacity to meet its own surface water supply needs as anticipated under phase 1 irregardless of the facilities' joint -use designation. Future expansions could be made of both of these facilities to meet the joint surface water supply needs of both Round Rock and Georgetown. 7. The successful financing of this project is possible based on the availability of financial assistance from one or more of the entities mentioned under the Feasibility Section. The possibility of joint -use of some of the facilities by Round Rock with Georgetown appears to be a positive advantage in gaining outside financial support of this project. B. Recommendations Recommend that the City of Round Rock initiate plans for the design, construction, and financing of the facilities outlined in this report necessary to obtain, treat, and transport surface water from the North Fork Reservoir to the City's existing water distri- bution system for municipal use. This action should be initiated immediately to ensure the continued uninterrupted supply of water to customers within the City of Round Rock's service area in the future. 6 SECTION III - EXISTING WATER SUPPLY SYSTEM A. Water Wells Water wells pumping from the Edward's Aquifer provide the only source of water for the City of Round Rock at the present time. The only treatment that is presently required is gas chlorination, prior to entering ground storage tanks. The present pumping capability of the City's water wells is tabulated, as follows in TABLE NO. 1. TABLE NO. 1 EXISTING WATER WELLS Well Pump Capacity Location (GPM) (MGD) Lake Creek 250 0.360 Lake Creek 1,250 1.800 Lake Creek 1,200 1.728 Lake Creek 3,000 4.320 Tower Drive 300 0.432 Westinghouse 300 0.432 Westinghouse 100 0.144 Brushy Creek 1,400* 2.016 Spring Street 1,400* 2.016 *Currently under construction. Of the above wells, both the 250 GPM Lake Creek and 300 GPM Tower Drive wells are not included in determining the City's existing ground water pumping capability due their shallow depth and susceptability to variations in the level of the Edwards Aquifer. 7 In addition, since both of the Westinghouse wells are, at the present time, not connected to the City's main centralized water distribu- tion system, these are also not included. Review of the remaining three Lake Creek wells and the new Brushy Creek and Spring Street wells indicates that, due to draw down of the aquifer level, all of these wells cannot be operated simultaneously. The most conservative approach to operation of these wells would be the operation of the 1,250 GPM and 1,200 GPM Lake Creek wells along with the new 1,400 GPM Brushy Creek well and holding the new 1,400 GPM Spring Street well as stand -by. This well operation combination yields a total available ground water pumping capability for the City of Round Rock of approximately 3,850 GPM to 5,250 GPM depending on the stand -by operation of the 1,400 GPM Spring St.well. For purposes of this report, the total available ground water pumping capability is assumed to be 5,000 GPM, or 7.20 MGD, which is within the above demonstrated range. It is noted that in all of the above assumptions, the level and recharge of the Edwards Aquifer is assumed to be normal. B. Ground Storage The City of Round Rock's existing ground storage consists of one 500,000 gallon tank located at the Bowman Road Pump Station, one 750,000 gallon tank located at the McNeil Road Pump Station, one 500,000 gallon tank located at the Lake Creek Pump Station and 162,000 gallons of the 500,000 gallon Tower Drive Standpipe, which is a total existing ground storage capacity of 1,912,000 gallons. In addition, the ground storage tank at the Westinghouse facility holds 100,000 gallons. However, since this facility is not tied into the 8 City's main water system, it does not, at the present time, affect the City's total existing ground storage capacity of 1,912,000 gallons. C. Elevated Storage Elevated storage at the present time consists of one 60,000 gallon elevated tank, located downtown, 338,000 gallons of the Tower Drive Standpipe, the 500,000 gallon Chisholm Valley West Standpipe, and the 750,000 gallon Business Highway 81 North Standpipe. This represents a total existing elevated storage capacity of 1,648,000 gallons. The Westinghouse facility has one 500,000 gallon standpipe of which 300,000 gallons of storage must be reserved for the Westinghouse Plant facility as a result of contractual obligations between the City of Round Rock and Westinghouse. Remaining is 200,000 gallons of elevated storage to serve customers other than Westinghouse. However, again due to the isolation of this facility, this 200,000 gallons does not affect the City's elevated storage capacity at the present time. 9 SECTION IV - WATER SUPPLY REQUIREMENTS A. Service Population Projections The City of Round Rock Planning Department has recently developed population projections for the City of Round Rock from the year 1979 to the year 1986. In addition, the developers of Brushy Bend Park and Brushy Creek developments, which are located west of the City and rely on the City for their water supply needs, have constructed population projections for these areas over the next several years. A summation of these population projections within the City of Round Rock's water service area together with an extrapolation of these projections through 1988 is presented in TABLE NO. 2. Year 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 12,700 14,500 15,800 19,300 22,500 26,000 30,100 35,100 40,000 45,500 TABLE NO. 2 POPULATION PROJECTIONS Round Rock Brushy Creek Population Development Population Total 10 1,088 1,856 2,624 3,392 4,160 4,928 5,695 6,464 7,232 8,000 13,788 16,356 18,424 22,692 26,660 30,928 35,795 41,564 47,232 53,500 These population projections will be used to determine water supply requirements for the City of Round Rock. B. Future Water Supply Requirements The City of Round Rock has an existing ground water pumping capability of approximately 7.2 MGD. This supply is possible when four water wells are pumping a total of 5,000 GPM for 24 hours in one day. A water supply of 7.2 MGD will serve a peak day water usage for approximately 16,000 persons. With a population projection of 16,356 persons in the City's service area by 1980, it is apparent that the existing ground water supply available to meet the City's future water demands is rapidly approaching its capacity. The total estimated water supply requirements to adequately serve the City of Round Rock along with the Brushy Creek developments are reflected in TABLE NO. 3 as follows: Year 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 Population Projection 13,788 16,356 18,424 22,692 26,660 30,928 35,795 41,564 47,232 53,500 TABLE NO. 3 WATER SUPPLY REQUIREMENTS (1979 - 1988) 11 Peak Daily Usage (3 X Average Daily Usage) (MGD) (GPM) 6.20 7.36 8.29 10.21 12.00 13.92 16.11 18.70 21.25 24.08 4,306 5,108 5,754 7,087 8,326 9,659 11,179 12,980 14,760 16,719 SECTION V - WATER SUPPLY SOURCES A. Ground Water Supply It is well to consider all potential sources for a long -range supply of water. One source is that of the present supply, the Edwards Aquifer. It is extremely difficult to determine the exact yield of the Edwards in the Round Rock area. The underground reservoir is supplied from precipitation penetration and intermittent streams crossing the Edwards outcrop. Discharge from the reservoir occurs through springs and wells. A report for the City of George- town in 1957 by William F. Guyton and Associates estimated the average discharge from the Edwards in the Georgetown area on the order of 4 to 8 million gallons per day, which is a 100% variation in capacity. This variation in yield might illustrate the difficulty of accurately estimating the ground water capability of the Edwards formation without extensive and time consuming studies of the area. The report also stated that a ground water divide probably exists between Round Rock and Georgetown, approximately 3 miles south of Georgetown. If this is correct, estimates of 4 to 8 MGD yield from the Edwards in Round Rock, based on the Edwards yield in Georgetown, may not be accurate. It is known that the yield of the Edwards Aquifer cannot exceed the average recharge. Thus, the total well pumpage from the aquifer should not exceed the safe yield. Round Rock presently has a 24 -hour pumping capability of approximately 7.2 MGD. If the Edwards recharge flow in Round Rock is approximately equal to the capacity of that in the Georgetown area (4 -8 MGD), Round Rock's withdrawal rate is approaching the maximum safe yield point during low stages of the Aquifer. 12 Another major factor to consider is the effect that an extended drought has on the ground water supply. This occurrence significantly reduces the well pumpage, which creates a serious shortage of water. The formation may also be, to some degree, subject to ground water contamination from septic tanks, feed lots, sewage collection systems and solid waste disposal sites. B. Surface Water Supply Based on the above discussion, the Edwards Aquifer will not be able to meet the City of Round Rock's steadily increasing demand for water supply in the future. Because of this, alternate sources of surface water supply are necessary for meeting the City's future water requirements. The amount of dependence on surface water the City will face in the future to meet its needs is reflected in TABLE NO. 4 as follows: TABLE NO. 4 SURFACE WATER SUPPLY REQUIREMENTS (1979 -1987) Population Peak Daily Usage Projection (3 X Average Daily Usage) Year (Over 16,000 persons)* (MGD) (Acre- Feet /Day) 1979 -0- -0- -0- 1980 356 0.16 0.48 1981 2,424 1.09 3.27 1982 6,692 3.01 9.03 1983 10,660 4.80 14.39 1984 14,928 6.72 20.15 1985 19,795 8.91 26.72 1986 25,564 11.50 34.51 1987 31,232 14.05 42.16 1988 37,500 16.88 50.63 13 *Population of 16,000 persons represents population that can be served by the City of Round Rock's existing well pumping capacity of 7.20 MGD. Several possible sources of surface water supply for the City were studied. These include the North Fork Reservoir, the South Fork Reservoir, Granger Lake and Lake Travis (See EXHIBIT B). 1. North Fork Reservoir - The North Fork Reservoir, located approximately 3.5 miles west of Georgetown on the North Fork of the San Gabriel River, is currently under construction. This reservoir, which is scheduled for completion in early 1979, is approximately 7 miles from the northern most city limits of the City of Round Rock, as the crow flies, or 11 miles based on the length of proposed water transmission line. The project is being constructed by the U.S. Army Corps of Engineers and is locally sponsored by the Brazos River Authority. The North Fork Reservoir has a drainage area of approximately 246 square miles and provides a reservoir capacity of approxi- mately 29,200 acre -feet based on the established conservation pool level of 791 ft. msl. Additional data concerning the North Fork Reservoir is provided as EXHIBIT A to this Report. By Permit to Appropriate State Water No. 2367, which was granted by the Texas Water Rights Commission on July 16, 1968, the Brazos River Authority is authorized to utilize a total of 14,200 acre -foot of water per annum for beneficial use. This represents the total amount of water the Authority can contract with other parties for use. Based on this, the Authority 14 has entered into water supply contracts with both the Cities of Georgetown and Round Rock for supply of 6.0 mgd, or 18.42 acre -feet per day (average use) of water. Both contracts are identical and set forth terms for determining the price for water made available, reserve water, rates of withdrawal of water, and metering the reporting. At present, the estimated cost to Round Rock is $0.18 per 1,000 gallons of water used plus $0.10 per 1,000 gallons of water reserved but not used. The actual unit price of water will be determined after con- struction of the North Fork Reservoir is completed. Pursuant to the executed Water Supply Contract By and Between Brazos River Authority and City of Round Rock, dated May 2, 1978, the City has been granted a Contractual Permit by the Texas Water Commission. This Permit authorizes the use of a total of 6,723 acre -feet of water annually (average withdrawal) for municipal water supply. The Contractual Permit, granted January 8, 1979, provides the necessary authority for the City to utilize surface water from the North Fork Reservoir under the existing Water Supply Contract. It is also noted that the City of Georgetown has been granted a similar contractual permit to utilize surface water from the North Fork Reservoir under its contract with the Brazos River Authority. 2. South Fork Reservoir - Also planned for the area is the South Fork Reservoir which has no scheduled date for beginning construction because, as yet, no Federal financing has been appropriated. The proposed location for the South Fork Reservoir 15 is approximately three miles from the northernmost city limits of Round Rock, four miles closer than the North Fork Reservoir. Due to the increasingly stringent environmental impact factors placed on such projects as the South Fork Reservoir by numerous private and governmental concerns along with the spiraling construction costs of such projects, it is uncertain at the present time whether or not the South Fork Reservoir will in fact ever become a reality. 3. Granger Lake - Granger Lake, located approximately eight miles east of Granger on the San Gabriel River, is currently under construction. This reservoir, which is tentatively scheduled for completion in September, 1980, is approximately 37 miles from the northern most city limits of the City of Round Rock. The project is being constructed by the U.S. Army Corps of Engineers and is locally sponsored by the Brazos River Authority. Granger Lake will have a conservation pool capacity of approximately 37,900 acre -feet. 4. Lake Travis - Another source of surface water is Lake Travis, located about 13.8 miles west of the city limits of Round Rock. The Lower Colorado River Authority controls the use of water from Lake Travis and at least seven water treatment plants presently exist on the lake. The reservoir has historically yielded a good quality raw water supply to its users. The Texas Department of Water Resources is presently developing an adjudi- cation of water rights for the Colorado River. 16 It is noted that a water authority is obligated to satisfy the 50 year water needs of its district before approval for water rights may be given to a user which lies outside the authority's district. Applicants that lie within a water authority's district have a higher priority for water rights than those applicants that are located outside of such district. Since the City of Round Rock is not within the Lower Colorado River Authority district, Round Rock would probably not be a preferred applicant for water rights out of Lake Travis. 17 SECTION VI - PROPOSED FACILITIES The basic facilities necessary to transport treated surface water from the North Fork Reservoir to the City of Round Rock's main centralized water distribution system include a raw water intake structure, a water treatment plant, and a treated water trans- mission line along with related booster pump and tank facilities. Various alternatives exist in relation to the sizing, location, and construction phasing of each of these required basic facilities. Each of these alternatives are discussed in the following paragraphs. A. Raw Water Intake Structure To obtain raw surface water from the North Fork Reservoir for the system, a raw water intake structure will be necessary. This structure will draw raw water from the reservoir and pump it to the proposed water treatment plant a short distance away. Basically two types of these structures could be utilized on the North Fork Reservoir; the fixed type or the floating barge type. 1. Fixed Intake Structure - This type of intake structure is well suited to construction prior to the impounding of water within a lake or reservoir. This is due to their requiring a substantial foundation structure for support and the expense associated with construction of such a structure where the water level has already reached the normal elevation. Fixed intake structures do have provisions for varying the raw water intake elevation within a limited range. Fixed intake structures are relatively expensive in comparison to floating types; however, they generally have a longer design life and require less maintenance than do floating intake structures. 18 2. Floating Intake Structure - This type of intake structure has the advantage of being able to remain in operation regard- less of fluctuations in the lake or reservoir elevation due to its floating design which allows it the flexibility to automa- tically adjust to the surface water elevation. With the floating intake structure arrangement, the raw water intake orifice along with the pumps are mounted directly on a floating barge and pump to shore via a flexible hose link. This is opposed to the fixed intake structure configuration which rigidly affixes all components to the shore. Because of their ability to be assembled on shore and floated into operating position, the floating intake structure is better suited to construction at a lake or reservoir site where water is already impounded. It is noted that the City of Georgetown has already financed the construction of a fixed intake structure along the northern shoreline of the North Fork Reservoir (See EXHIBIT C). The structure consists of three submersible pump casings with a design capacity of 6.0 MGD with one pump held as a stand -by. Based on the anticipated City of Round Rock's annual surface water supply requirements (See TABLE NO. 4), the first phase of the required raw water intake structure should have a minimum design capacity of 6.0 MGD, or 4,200 GPM. With the water treatment plant divided into two basic units of 3.0 MGD each, it is desireable to be able to operate only one -half of the plant facility during low demand periods. Therefore, the intake structure should be sized with three pumps, each with a capacity of 3.0 MGD. This would 19 allow the operation of two pumps at peak flow conditions (6.0 MGD - first phase) and have one pump as a stand - by. This arrangement would work at the existing Georgetown fixed intake structure or from a floating intake structure. The phase 1 intake structure would have to be expanded to 18.0 MGD in the future to meet the surface water supply requirements of the City of Round Rock. Transfer of water from the raw water intake structure to the proposed water treatment plant will be accomplished via a raw water transmission line. Presently, there exists a 16 inch line con- structed by the City of Georgetown which extends from the existing fixed intake structure to a proposed site for a water treatment plant. This existing line has a capacity of 6.0 MGD which is also the recommended capacity of phase 1 of the raw water transmission line for the City of Round Rock. As is the case with the intake structure, the City of Round Rock will ultimately require a 18 MGD capacity raw water transmission line to meet its own surface water supply requirements. B. Water Treatment Plant Treatment of raw surface water from the North Fork Reservoir will be accomplished at a water treatment plant located adjacent to the reservoir itself. The water treatment process utilized will be a modified conventional process which consists of chemical addition (chlorine and alum), mixing, flocculation, clarification (settling), filtration, and post chlorination (See EXHIBITS D and E). 1. Chemical Addition - Pre - chlorination in the treatment process disinfects raw water which inactivates most bacteria and helps 20 control algae growth within the treatment units. Aluminum sulfate (Alum) is added as a flocculant agent. Alum is added for flocculation and coagulation prior to the settling and clarification basins. 2. Rapid Mixing Basins - The initial mixing of chemicals (chlorine and alum) and recycled sludge from the clarifier with the raw water takes place in the rapid mixing basin. From the basin the mixed water is channeled to the flocculation basins. 3. Flocculation - The coagulation of colloidal and finely divided suspended matter by the addition of floc- forming chemicals (Alum) takes place immediately after the rapid mixing chamber in the flocculation chamber. In other words, the flocculating is where the small pin point flocs grow into large settleable flocs. From the flocculation chamber the floc -laden water flows on to the clarifer. 4. Clarification - The clarifier is a chamber for separating the solids (floc) from the clear supernatant water. The clear water goes to the filters and the sludge settles to the bottom of the clarifier and is collected by mechanical scrapers and is either recycled back into the process (at the rapid mix chamber) or wasted to the sludge lagoons. 5. Filtration - Particulate suspended matter is collected in the filters where the particulate matter penetrates into the pores of the filter bed and adheres to the grains of the filter media. As more and more particles are trapped in this fashion 21 the free passage through the filter is diminished. At the end of the filter run the filter will be nearly plugged with particulate matter. Periodic back washing (reversing the flow direction through the filter) is required to clean the surface of the filter for efficient flow- through operation. The multi- media filter consists of (2) different types and sizes of filter media. This allows higher capacity with quality filtration and minimized disturbance during the back wash cycle. Filtration is the final treatment process step. The effluent is chlorinated and pumped to the ground storage tank for detention prior to delivery to the distribution system. 6. Post - Chlorination - Post - chlorination (after the treatment process) is required for further disinfection. A 20 minute detention time and a chlorine residual of 1 mg /1 after the detention is required prior to customer service. Post - chlorination occurs within the clearwell. 7. Clearwell - The clearwell provides needed detention time for post - chlorination in addition to a minimal amount of temporary storage capacity. This storage capacity is utilized to "flatten" the peak flow demand curve imposed upon the water treatment plant by water users within the City's service area and avoid fluctuations in operating the water treatment plant. Phasing of the construction of the water treatment plant will allow increasing the capacity of the plant to coincide with the treated surface water supply needs of the City. Phase 1 capacity is 22 intended to provide 6.0 MGD of treated surface water with further capacity increases required in the future up to an ultimate capacity of 18 MGD. Several alternatives exist for the location of the water treatment plant site adjacent to the North Fork Reservoir. The proposed site of the City of Georgetown's water treatment plant is on the northern side of the Reservoir (See EXHIBIT C). This site will be served by the existing fixed raw water intake structure and raw water transmission line (both of which were also constructed by the City of Georgetown) and has sufficient area to accommodate the construction of a water treatment plant of adequate capacity to meet the ultimate treated surface water supply requirements of both the Cities of Georgetown and Round Rock, a total of 36 MGD (See EXHIBIT F). Utilization of this existing site would involve the joint use of all facilities, i.e. intake structure, raw water transmission line, and treatment plant, by both participating cities. An alternate site would be one located along the southern shore of the North Fork Reservoir (See EXHIBIT C). Such a location would be approximately 3,600 feet closer to the City of Round Rock and offer the further advantage of avoiding the crossing of the North Fork of the San Gabriel River with the treated water transmission line. However, since this site is on the opposite shore from the existing facilities constructed by the City of Georgetown, selection of this site for the construction of the water treatment plant would negate any joint -use benefits that might exist through the joint -use of facilities with the City of Georgetown. 23 C. Treated Water Transmission Line The transportation of treated surface water from the clearwell at the proposed water treatment plant at the North Fork Reservoir site to the existing 500,000 gallon standpipe along Business Highway 81 North will be accomplished via an underground waterline. Design sizing of this waterline has been developed utilizing a .- staging concept to promote optimum economy in both construction and operation of the proposed waterline. 1. Route Selection - Routing of the proposed waterline from the North Fork Reservoir to the existing 500,000 gallon standpipe along Business Highway 81 North was selected taking into account natural land topography, existing property lines and owners, the necessity for acquiring easements for the waterline and the avoidance of existing developed areas. The routing selected, as shown in EXHIBIT G, is tentative and subject to change in the future. A special feature of the routing is the incorporation of the existing 18 inch waterline crossing under IH 35 at Rabbit Hill Road and the linking of the Westing- house water supply facility to the City of Round Rock's main centralized water distribution system with a phase 1 tie -in to the existing 12 inch waterline at Chandler Road. The general routing will originate at the water treatment plant site on the north side of the reservoir and proceed south across the North Fork of the San Gabriel River through a water- line crossing area assigned by the U.S. Government (Re: July 20, 1978, letter from the Department of the Army to Mayor Ray Litton). In this area the pipeline will have to be located a 24 minimum of 500 feet from the down stream toe of the dam enbank- ment, and will also have to be downstream of the outlet works channel, the spillway channel, and the alternate site for the canoe concession area. From here the waterline routing generally follows existing property lines southward to Texas Highway 29 where it veers westward before crossing the South Fork of the San Gabriel River and routing southward to F.M. 2243. From this point the waterline runs westward a short distance along F.M. 2243 before again turning southward to the proposed new 1031 standpipe (service level 3) which is located at the highest elevation along the proposed waterline routing which was chosen to minimize the design height of the proposed standpipe. From the proposed new 1031 standpipe the waterline runs southeasterly along existing property lines on through the Texas Crushed Stone Property to IH 35. It is noted that within this area the tentative waterline routing avoids all quarrying operations currently underway. The waterline then utilizes existing right -of -way southward along IH 35 to the existing 500,000 gallon standpipe along Business Highway 81 North. Crossing of IH 35 is made at the Rabbit Hill Underpass. As shown is EXHIBIT G, the proposed routing utilizes existing property lines and right -of -ways as much as possible. This is due to the fact it is anticipated to be much easier to obtain necessary easements for the waterline along these areas than across open land tracts and within areas of existing development. A property ownership survey has been conducted in conjunction 25 with the preparation of this report to determine the property owners that would be affected by the proposed waterline routing. This is also included as EXHIBIT G and represents the parties from which easements would be required if the proposed routing were selected. The majority of the waterline will be class 150 rated pipe with some class 200 pipe located at low elevation creek and river crossings. 2. Phase 1 - Phase 1 of the waterline will include proposed Lines 1, 2, 3 and 5 and will provide a complete link between the North Fork Reservoir and the City of Round Rock (See EXHIBIT H). Phase 1 is designed to deliver a total of 3.0 MGD of treated surface water from the North Fork Reservoir to the City and will tie in the Westinghouse facility to the City's system. Based on surface water supply requirements provided in TABLE NO. 4, the City's surface water supply requirements will exceed 3.0 MGD during 1982. Line 1 will run from the water treatment plant at the North Fork Reservoir to F.M. 2243. It is designed to be 30 inches in diameter, approximately 36,000 feet long, and will be made of concrete steel cylinder (C.S.C.) or ductile iron (D.I.). Line 2 will run from F.M. 2243 to the proposed 1031 standpipe. Line 2 is the same size and type as Line 1 and will be approxi- mately 7,400 feet long. 26 Line 3 will link the proposed 1031 standpipe to the existing 18 inch C.S.C. line crossing underneath IH 35 at the Rabbit Hill Underpass. Line 3 is the same size and type as Lines 1 and 2 and will be approximately 11,200 feet long. Lines 1, 2, and 3 are all designed for the ultimate flow of 18 MGD. Line 4A is an existing 18 inch C.S.C. line which extends for 400 feet under IH 35. It will be utilized in Phase 1 without modification. Line 5 will complete the waterline link between existing Line 4A and existing Line 6A. Line 5 is the same size and type as Lines 1, 2 and 3 and will be approximately 7,100 feet long. it is also designed for the ultimate flow of 18 MGD. Line 6A is an existing 12 inch asbestos - cement line which extends northward from the existing 750,000 gallon standpipe along Business Highway 81 North to Chandler Road. 3. Phase 2 - Phase 2 of the waterline is designed to increase the flow from 3.0 MGD to 6.0 MGD. This could be accomplished, depending on the locations of water demands, by the addition of Line 6B parallel to the existing Line 6A (See EXHIBIT H). Line 6B is tentatively designed to be 30 inches in diameter, approximately 8,300 feet long, and would be made of concrete steel cylinder (C.S.C.) or ductile iron (D.I.). Based on surface water supply requirements provided in TABLE NO. 4, the City's surface water supply requirements will exceed 6.0 MGD during 1984. 27 4. Phase 3 - Phase 3 of the waterline is designed to increase the flow from 6.0 MGD to the waterline's ultimate design capacity of 18.0 MGD. This will be accomplished by the addition of Line 4B in parallel to the existing Line 4A under IH 35 (See EXHIBIT H). Line 4B is designed to be 24 inches in diameter, approximately 400 feet long, and will be made of concrete steel cylinder (C.S.C.) or ductile iron (D.I.). Based on surface water supply requirements provided in TABLE NO. 4, the ultimate design capacity of the proposed waterline, 18.0 MGD, will meet the City's surface water supply requirements through 1988. D. Booster Pump Stations and Standpipe 1. Booster Pump Station at Water Treatment Plant - This station will provide the necessary pressure to deliver the desired quantity of treated surface water via the treated water trans- mission line to the new 1031 standpipe located south of F.M. 2243. Phase 1 of this station is designed for a delivery flow of 6.0 MGD. Four vertical turbine pumps will provide the needed pressure with one pump acting as stand -by. The Phase 1 station will require expansion in the future to provide an ultimate delivery capacity of 18 MGD. 2. 1031 Standpipe - This proposed standpipe will function as an elevated storage tank for water service level no. 3 and will have an overflow elevation of 1031 feet msl. This standpipe will be filled by pressure provided by the booster pump station 28 located at the water treatment plant and provide gravity flow from its location southward to the existing 750,000 gallon Business Highway 81 North Standpipe and the existing City of Round Rock water distribution system. This utilization of gravity flow for a distance of approximately 27,000 feet will allow significant savings in pumping costs. 29 SECTION VII - BASIS OF DESIGN Calculations detailing the design criteria for each of the proposed facilities required for obtaining, treating, and transporting surface water from the North Fork Reservoir to the City of Round Rock are presented herein. In all cases, meticulous attention to detail has been paid to maximize efficiency and minimize cost of all of the proposed facilities. A. Raw Water Intake Structure 1. Phase 1 - Design Capacity = 6.0 MGD (4,200 GPM) Three pump design with each pump rated at 2,100 GPM Static: Highest Elevation - plant site (Georgetown site). . . 890' Lowest Elevation - minimum water elevation 735' Static Head 155' (67 psi) Friction: 3,100' of 16 inch raw water transmission line at 4,200 GPM Friction Loss = 45' (20 psi) Total Dynamic Head (TDH): TDH = 155' (static) + 45' (friction) = 200' (87 psi) Each pump (3) will require a 150 HP motor. 2. Ultimate - Design Capacity = 18.0 MGD (12,500 GPM) Seven pump design with each pump rated at 2,100 GPM 30 Static: Highest Elevation - plant site (Georgetown site). . . 890' Lowest Elevation - minimum water elevation 735' Static Head 155' (67 psi) Friction: 3,100' of 30 inch raw water transmission line at 12,500 GPM Friction Loss = 16' (7 psi) Total Dynamic Head (TDH): TDH = 155' (static) + 16' (friction) = 171' (74 psi) Each pump (7) will require a 150 HP motor. B. Water Treatment Plant Flow Scheme - (See EXHIBIT D) Raw water intake pumps to rapid mix basin. Mix with chlorine and coagulation chemicals. Rapid mix basin to flocculation basin. Flocculation basin to clarification basin. Clarification basin to filtration units. Filtration units to ground storage tank. Phase 1 Peak Flow = 6.0 MGD (4,200 GPM) Treatment Process: modified conventional Chemical Flocculant: aluminum sulfate (alum) or ferrous sulfate (FeSO4 7 H (determination made based on PH of raw water) 31 Coagulation Feed Pumps: operating at 4,200 GPM 4,200 X 1,440 X 30 x 8.34 _ 1,500 # /day 1,000,000 Other Chemicals Required: chlorine (pre - chlorination and post - chlorination) Chlorination Pumps: Pre - chlorination (operation at 4,200 GPM) Post - chlorination Plant flow divided into two (2) equally sized, parallel basins. Peak flow to each basin = 3.0 MGD (2,100 GPM) 1. Rapid Mix Basin Dimensions: 10' - 0" X 8' - 6" X 15' - 6" SWD Volume: 1275 ft. 9538 gallons Volume of Baffled Areas to Prevent Short Circuiting of Flow: Inlet Baffle: 1' - 6" X 5' - 0" X 10' - 0" Volume: 75 ft. 561 gallons Backwash Baffle: 1' - 6" X 3' - 0" X 6' - 0" Volume: 27 ft. 202 gallons Net Rapid Mix Volume: 1,173 ft. 8,775 gallons Detention Time at Peak Flow: 2.1 minutes (approx. 2 minutes ideal) Water H.P. = GPM X H X 8.34 33,000 Velocity = 4.36 FPS Air Flow = 100 SCFM Area = 7(d _ 11(2) - 3.14 ft. 4 4 4,200 X 1,440 X 12 X 8.34 32 1,000,000 600 # /day 4,200 X 1,440 X 5 X 8.34 _ 250 # /day 1,000,000 Q = AV = 4.36 fps X 3.14 ft. = 13.7 cfs = 6,145 GPM H= 12 ft. Water H.P. = 6,145 gpm X 12 ft. X 8.34 lb /gal. 33,000 Water H.P. = 18.6 ft. lb /sec. W = WHP X 550 _ (18.6)(550) _ 8.74 Vol. 1,173 G = Velocity Gradient G I 0.18 8.7X 4 10 -4 = 697 sec. -1 (500 sec. -i to 1,000 sec. -1 desirable) 2. Flocculation Aerated Channel (2 each - each carrying 1/2 Q) Dimensions: 34' - 0" X 8' - 0" X 15' - 6" SWD Volume: 4,216 ft. 31,540 gallons Use 15 each air diffusers SCFM /diffuser (peak) 5.0 Submergence: 12' - 9" Spacing: 2' - 0" c/c Total air flow to each channel: 75 SCFM (Peak) Detention Time at Peak Flow (0.5Qp): 15.1 minutes Power (P) = 81.5 QA log 10 [(H + 34)/34] Peak (P) = (81.5) (75) (0.14) = 843.5 ft. -lb. /sec. Velocity Gradient (G) = KV V = 4,216 ft. /4@ 27 °C = 0.18 X 10 -4 Gp =1 843.5 X 104 _ 105 sec. -1 .18 (4,216) Peak Flow Rate = 2085 GPM = 4.65 cfs 33 Maintain Velocity 5 1 fps through channels to avoid shearing floc. Area of port from aerated channel to Paddle Floc Zone = Q = 4.65 cfs = 4.65 ft. (min.) V • 1.0 fps Use 6 each 1 ft. square ports evenly spaced in wall between basins = 6 ft. Locate bottom of port 2' - 0" above tank floor. Paddle Flocculator (2 each - each carrying 1/2 Q) Dimensions: 16' - 0" X 34' - 0" X 15' - 6" SWD Volume: 8,432 ft. 63,080 gallons Detention Time at Peak Flow (0.5 Qp) 30.2 minutes (TDH minimum) Total Flocculation Time at Peak Flow 45.4 minutes (Aerated Channel plus Paddle Zone) Paddle Area 8 each X 5 - 1/2' wide X 13.25 long = 48.6 SF (X 2 each vertical 12 flocculators) 48.6 X 2 X 100 = 18.5 < 20 %, therefore rolling should not occur. 34 X 15.5 — Power = CD A p" 2 CD = 1.9 A = 48.6 ft. P = 1.94 = Approximately 75% peripheral speed of paddles Paddle Speed, Vp usual range 0.6 - 2.5 fps Use Vp = 2.0 fps ' = 0.75 (2.0) = 1.5 fps 3 P = (1.9)(97.2)(1.94)(1.5) = 604.6 ft. lb. /sec. 2 34 G =1 604.6 X 104 = 63 sec. -1 0.18 (8,432) 3. Clarifier - (2 each carrying 1/2 Q) Dimensions: 71' - 0" X 34' - 0" X 15' - 0" SWD Gross Volume: 37,220 ft. 278,450 gallons (71' X 34' X 15') + 1/3 7'(17') (1.67) (2) Net Volume: 33,450 ft. 250,240 gallons (less fillets in corners & floc. inlet) Surface Area: (71 - 5) X 34 = 2,244 ft. Peak Surface Rate = 0.93 fpm /ft. Detention Time at Peak Flow (.5 Q) = 120 minutes (TDH minimum) Total Weir Length = 220 LF Weir Overflow Rate (@ Peak Flow) 9.5 GPM /ft. 13,650 GPD /ft. 4. Multi -Media (Coal -Sand) Gravity Filters - Filter Flow Rate = 5 GPM /ft. Peak Flow = 4,200 GPM 4,200 GPM - 840 ft. Filter Bed Area 5 GPM /ft. Use multiple filter cells to minimize filter backwash rate. Backwash water returned directly back into process at rapid mix basin. Flow split between two sets of cells. 1 /2Q = 2,100 GPM 840 ft. - 420 ft. 2 Each side of the treatment unit designed to operate at peak flow capacity with one filter cell out of operation. 7 units @ 8 ft. X 8 ft. = 1,024 ft. 35 14 filter cells = 896 ft. (840 ft. required) Filter Bed: 6" pea gravel 12" sand 18" anthrafilt Backwash rate at 50% expansion. Anticipate summer water temperature of 87 ° F - provide for maximum backwash rate of 20 GPM /ft. Each filter unit = 64 ft. 20 GPM /ft. X 64 ft. = 1,280 GPM /Cell Backwash piping 16 inch at 2 FPS velocity. C. Raw Water Transmission Line (1980 - 1982 Design - Phase 1) North Fork Surface Water Supply - 3 MGD Peak (2,100 GPM) 3 MGD ; 450 GPCPD = 6,700 persons Existing Water Well Supply - 7.2 MGD Peak (5,000 GPM) 7.2 MGD 450 GPCPD = 16,000 persons Total Water Supply - 10.2 MGD Peak (7,100 GPM) 10.2 MGD 450 GPCPD = 22,700 persons Based on service population projections for the City of Round Rock presented in TABLE NO. 2, a service population of 22,700 persons will be reached during 1982. 1. Water Treatment Plant Site (North side of Dam) to New 1031 Standpipe - 36 Static: Highest Elevation - overflow of new 1031 standpipe (915' N.G. + 116' tank) 1031' Lowest Water Elevation - clearwell at pump station 880' Static Head 151'(65 psi) Friction: Line 1 and 2 pipe length, size, and type: 43,400 L.F. of 30" C.S.C. or D.I. Q = 2,100 GPM C = 120 Friction Loss Factor = 0.019'/100' Friction Loss = 43,400' X 0.019'/100' = 9' (4 psi) Total Dynamic Head (TDH): TDH = 151' (static) + 9' (friction) + 10' (miscellaneous) = 170' (74 psi) 2. New 1031 Standpipe to Existing Business Highway 81 North Standpipe Static: Highest Elevation - overflow elevation of new 1031 standpipe 1031' Lowest Elevation - overflow elevation of existing 750,000 gallon standpipe @ Business Hwy. 81 North . . 893' Total Available Static Head 138'(60 psi Friction: Q (as shown below) C = 120 37 Friction Loss Factor (as shown below) Line 3 (30" C.S.C. or D.I., 2,100 GPM) 11,200' X 0.019'/100' = 3' Line 4A (Existing 18" C.S.C., 2,100 GPM) 400' X 0.17'/100' = 1' Line 5 (30" C.S.C. or D.I., 2,100 GPM) 7,100' X 0.019'/100' = 2' Line 6A (Existing 12" A.C., 2,100 GPM) 8,300' X 1.17'/100' = 79' Total Friction Loss 103'(45 psi) Excess Head Available: Excess Head Available = 138' (static) - 103' (friction) - 5' (miscellaneous) = 30' (13 psi) D. Raw Water Transmission Line (1983 - 1984 Design - Phase 2) North Fork Surface Water Supply - 6 MGD Peak (4,200 GPM) 6 MGD ; 450 GPCPD = 13,300 persons Existing Water Well Supply - 7.2 MGD Peak (5,000 GPM) 7.2 MGD ; 450 GPCPD = 16,000 persons Total Water Supply - 13.2 MGD Peak (9,200 GPM) 13.2 MGD 450 GPCPD = 29,300 persons Based on service population projections for the City of Round Rock presented in TABLE NO. 2, a service population of 29,300 persons will be reached during 1984. 38 1. Water Treatment Plant Site (North side of Dam) to New 1031 Standpipe Static: Highest Elevation - overflow of new 1031 standpipe (915' N.G. + 116' tank) 1031' Lowest Water Elevation - clearwell at pump station 880' Static Head 151' (65 psi) Friction: Line 1 and 2 pipe length, size, and type: 43,400 L.F. of 30" C.S.C. or D.I. Q = 4,200 GPM C = 120 Friction Loss Factor = 0.049'/100' Friction Loss = 43,400' X 0.049'/100' = 22' (1.0 psi) Total Dynamic Head (TDH): TDH = 151' (static) + 22' (friction) + 15' (miscellaneous) = 188' (82 psi) 2. New 1031 Standpipe to Existing Business Highway 81 North Standpipe Static: Highest Elevation - overflow elevation of new 1031 standpipe 1031' Lowest Elevation - overflow elevation of existing 750,000 gallon standpipe @ Business Hwy. 81 North . . 893' Total Available Static Head 138'(60 psi. 39 Friction: Q (as shown below) C = 120 Friction Loss Factor (as shown below) Line 3 (30" C.S.C. or D.I., 4,200 GPM) 11,200' X 0.05'/100'=6' Line 4A (Existing 18" C.S.C., 4,200 GPM) 400' X 0.74'/100' = 3' Line 5 (30" C.S.C. or D.I., 4,200 GPM) 7,100' X 0.05'/100' = 4' Line 6A (Existing 12" A.C., 400 GPM) 8,300' X 0.05' /100' = 5' Line 6B (30" C.S.C. or D.I., 3,800 GPM) 8,300' X 0.04'/100' = 4' Total Friction Loss 22' (10 psi) Excess Head Available: Excess Head Available = 138' (static) - 22' (friction) - 5'(miscellaneous) = 111' (49 psi) E. Raw Water Transmission Line (Ultimate Design - Phase 3) North Fork Surface Water Supply - 18 MGD Peak (12,500 GPM) 18 MGD = 450 GPCPD = 40,000 persons Existing Water Well Supply - 7.2 MGD Peak (5,000 GPM) 7.2 MGD : 450 GPCPD = 16,000 persons 40 Total Water Supply - 25.2 MGD Peak (17,500 GPM) 25.2 MGD + 450 GPCPD = 56,000 persons 1. Water Treatment Plant Site (North side of Dam) to New 1031 Standpipe Static: Highest Elevation - overflow of new 1031 standpipe (915' N.G. + 116' tank) 1031' Lowest Water Elevation - clearwell at pump station 880' Static Head 151' (65 psi Friction: Line 1 and 2 pipe length, size, and type: 43,400 L.F. of 30" C.S.C. or D.I. Q = 12,500 GPM C = 120 Friction Loss Factor = 0.363'/100' Friction Loss = 43,400' X 0.363'/100' = 158' (69 psi) Total Dynamic Head (TDH): TDH = 151' (static) + 158' (friction) + 20' (miscellaneous) = 329' (143 psi) 2. New 1031 Standpipe to Existing Business Highway 81 North Standpipe Static: Highest Elevation - overflow elevation of new 1031 standpipe 1031' 41 Lowest Elevation - overflow elevation of existing 750,000 gallon standpipe @ Business Highway 81 North . . . . 893' Total Available Static Head 138'(60 psi) Friction: Q (as shown below) C = 120 Friction Loss Factor (as shown below) Line 3 (30" C.S.C. or D.I., 12,500 GPM) 11,200' X 0.3637100' = 40' Line 4A (Existing 18" C.S.C., 4,000 GPM) 400' X 0.53'/100' = 2' Line 4B (24" C.S.C. or D.I., 8,500 GPM) 400' X 0.52'/100' = 2' Line 5 (30" C.S.C. or D.I., 12,500 GPM) 7,100' X 0.36'/100' = 26' Line 6A (Existing 12" A.C., 700 GPM) 8,300' X 0.15' /100' = 12' Line 6B (30" C.S.C. or D.I., 11,800 GPM) 8,300' X 0.33'/100' = 28' Total Friction Loss 100' (48 psi) Note: The 12,500 GPM flow rate is apportioned between parallel lines with A and B designations. Excess Head Available: Excess Head Available = 138' (static) - 120' (friction) - 10' (miscellaneous) = 18' (8 psi) 42 F. Booster Pump Stations 1. Booster Pump Station at Water Treatment Plant Phase 1 Design Capacity = 6.0 MGD (4,200 GPM) Vertical Turbine Pumps (4): Two Pumps - 1,050 GPM @ 329' TDH, 125 HP Two Pumps - 2,100 GPM @ 329' TDH, 250 HP One 2,100 GPM pump included above will be utilized as stand -by. To economize on electrical energy costs, the four initial booster pump's impellers will be selected to satisfy 188' TDH up to 6.0 MGD pump delivery. One additional pump impeller in each pump will be added in the future to allow the pumps to deliver the stated design flow at 329' TDH while operating with additional future pumps. The pump motors and pump cans will be sized to accommodate the addition of pump impellers. 2. 1031 Standpipe Ultimate 18 MGD water treatment plant will serve 40,000 persons on a peak summer day. Elevated Storage: Equalization: 20% of one day's storage @ 150 GPCPD 40,000 capita X 150 X 20% = 1,200,000 gallons Fire: 10 hrs. storage @ 130 GPCPD 40,000 capita X 130 X 10/24 = 2,167,000 gallons Sum 3,367,000 gallons 43 Emergency: 25% of sum of equalization and fire 25% X 3,367,000 = 841,750 gallons Total elevated storage = 4,208,750 gallons Round to 4,200,000 gallons of elevated storage. Phase 1 Standpipe Ultimate Additional Elevated Storage Total Ultimate Elevated Storage 44 2 0 MG 2 2 MG 4 2 MG SECTION VIII - PRELIMINARY COST ESTIMATES A preliminary cost estimate has been prepared for phase one of the project and is presented below in TABLE NO. 5. It includes cost approximations for construction of all of the proposed phase one facilities necessary to obtain, treat, and transport surface water from the North Fork Reservoir to the City of Round Rock's existing main water system. These cost approximations have been developed based on the construction costs associated with projects of similar scope and nature. A 10% contingency factor has been added as an additional seperate item to cover any unexpected in- creases in the cost of labor and materials. The preliminary cost estimate also includes cost approximations for legal fees and financial advisor fees that would normally be expected to be incurred with the financing of the project. No direct costs have been estimated for the cost of land acquisition for the necessary easements for the facilities. However, it is anticipated that these costs, if required, can be accounted for with contingency funds. Item 1. Intake Structure (6.0 MGD) 2. Water Treatment Plant (6.0 MGD @ $0.32 /gallon) TABLE NO. 5 PRELIMINARY COST ESTIMATE - PHASE ONE Amount 3. Waterline (Ult. 18 MGD) (30" line; 48,450' Cl. 150 @ $55 /foot) (30" line; 13,250 Cl. 200 @ $58 /foot) $ 300,000 1,920,000 2,664,750 768,500 4. Clearwell (1.0 MG @ $0.13 /gallon) 130,000 45 Item 5. Booster Pump Station (Water Treatment Plant Site) 6. Standpipe (2.0 MG @ $0.25 /gallon) Sub -Total 7. Engineering Fees 8. Contingencies Total Construction Cost 9. Legal Fees 10. Fiscal Agent Fees Total Project Cost 46 Amount $ 165,000 500,000 $ 3,448,250 370,650 645,000 $ 7,463,900 75,000 20,000 $ 7,558,900 NOTES: (1) Engineering fees including preliminary, design, and construction phase services are determined in accor- dance with established curves for projects of similar scope and nature. Construction staking and daily inspection fees are not included, but would be accounted for with contingency funds. (2) Legal fees estimated at approximately 1% of total pro- ject cost. (3) Fiscal agent fees estimated at approximately 0.27% of total project cost. Based on this preliminary cost estimate for phase one, the cost of obtaining, treating and transporting surface water from the North Fork Reservoir to the City of Round Rock is approximately $7,558,900 with a probable range of between $7.3 million to $7.7 million. It is noted that'pha'se one costs can be reduced by approximately $200,000 if the water treatment plant is located along the southern shoreline of the North Fork Reservoir which would save approximately 3,600 feet of waterline. 47 SECTION IX - FEASIBILITY As indicated in the Preliminary Cost Summary for the project (see TABLE NO. 5), the estimated cost for completing phase 1 of the project is $7,558,900. This represents the cost of providing 6.0 MGD of treated surface water from the North Fork Reservoir to the City of Round Rock for municipal use. In meeting the costs of acquiring treated surface water for municipal use, the City faces various alternatives for financing. Several alternatives exist and are explored briefly in the following paragraphs. Each one offers different advantages to the City in meeting the costs of this project and require varying conditions and requirements from the City to qualify. The first source of funds to meet the costs of this project is through the selling of municipal bonds by the City of Round Rock itself. This would involve voting bonds for this specific purpose and determining the ability of the City to meet annual debt service requirements to bond holders. By virtue of selling its own bonds, the City would be relying strictly on its own ability to meet these annual debt service requirements. Two sources of revenue exist for the City to meet these annual debt service requirements; ad valorem property taxes and operating revenue from water and sewer service. Based on the magnitude of this project, the financial burden placed on the City if it were to attempt 100% financing of this project would undoubtably dictate a substantial increase in both taxes and service charges. A second source of funds is the Farmers Home Administration (FmHA). FmHA makes loans to eligible cities for financing water 48 improvement projects such as this. These loans bear a very low interest rate of 5% per annum which serves to decrease the annual debt service requirements. Due to the nature of this project, the ability to qualify for FmHA financing would probably be significantly improved if the project were constructed to the extent possible on a joint -use basis. The Brazos River Authority (BRA) represents another source of financing. As local sponsor for the North Fork Reservoir project itself, the BRA is in a unique position to provide supplemental funding to the City of Round Rock. As in the case with the FmHA, it is anticipated that the ability of the City to receive supplemental funding for the project would be significantly improved if the facilities were constructed to the extent possible on a joint -use basis. Water development loans made by the Texas Department of Water Resources offer a fourth source of funding for this project. The City has in the past qualified for one of these loans which it utilized to fund the Brushy Creek and Spring Street wells currently under construction. The interest rate of these loans are less than which the City could probably obtain on its own bonds. Private banks and lending institutions represent the last source of funding which might be available to the City for this project. However, loans made by these would carry higher interest rates than any of the previously mentioned types and would necessitate higher debt service requirements for the City to meet. 49 SECTION X - LIST OF EXHIBITS A - NORTH FORK RESERVOIR DATA B - RESERVOIR LOCATION MAP C - RESERVOIR AREA LAYOUT D - SCHEMATIC FLOW DIAGRAM - Water Treatment Process E - WATER TREATMENT PLANT - Equipment Layout F - 36 MGD ULTIMATE CAPACITY WATER TREATMENT PLANT - Site Plan at Georgetown Plant Site G - TRANSMISSION LINE ROUTE SELECTION AND PROPERTY OWNERSHIP MAP H - TRANSMISSION SYSTEM HYDRAULIC PROFILE 50 MI M I — IM — — — N — IM — — MI = LOCATION: R.M. 4.3 on the North Fork of the San INFLOW: Gabriel River, Brazos River Basin, 3.5 miles west Spillway design flood peak,._cfs of Georgetown, Texas Spillway design flood volume, ac-ft Spillway design flood runoff, inches DRAINAGE AREA: 246 square miles One inch of runoff DAM: Type: Length: Maximum Height: Top Width: SPILLWAY: Crest Elev. Length: Type: Feature 834.0 750' Broadcrested (ungated) Top of Dam Maximum Design Water Surface Top of Flood Control Pool (Spillway Crest) Top of Conservation Pool Maximum Tailwater Sediment Reserve Total Storage Streambed 13,120 ac -ft Rock fill, impervious core 6,700' (including spillway) 164' 40' : Reser- : Reservoir Capacity . : Elev : voir : Accutmx- : : Incre -: Spillway : Outlet Works : Feet : Area : lative : Runoff : mental: Capacity : Capacity : (msl) : (acres) : (ac -ft) : (inches): (ac -ft): (cfs) : (cfs) 861.0 5,570 856.0 5,070 220,100 16.78 265,800 834.0 3,220 130,800 9.97 87,600 791.0 1,310 37,100 2.83 29,200 750.4 699.0 EXHIBIT A NORTH FORK RESERVOIR DATA *Sediment distributed as follows: 7,900 ac -ft below elev 791.0 6,100 ac -ft between elev 791.0 and 834.0 OUTFLOW: Total routed peak outflow, cfs 270,000 Spillway 265,800 w Outlet Works 4,200• OUTLET WORKS: Type: One gated conduit Dimension: 11 -foot diameter Invert Elev: 720.0 Control: 2 - 5'X 11' hydraulically operation slide gates POWER FEA7.47RES: None 14,000* 130,800 4,700 4,900 3,900 395,800 336,800 25.67 AUTHORIZATION: Flood Control Act of 1962, approved IOW FLAW OUTLETS (EMPTYING INTO FLOOD WNPROL CONDUIT): 23 Oct. 62 (PL 874/87/2) (HD 591 /82/2) Intake dimensions: 3' X 4' Number: 4 OPERATION AND MAINTENANCE COSTS: Control: 1 -3' X 4' manually operated slide gate at each Federal $ 292,200 intake Non - Federal 95,700 Total $ 387,900 Intake invert elevations: Highest level - 777.0 CURRENT APPROVED COST ESTIMATE: Upper intermediate level - 763.0 Federal $ 29,900,000 Lower intermediate level - 749.0 Non - federal None* Lower level - 735.0 (Oct 76) Total $ 29,900,000 '%∎ STATUS OF PROJECT: Deliberate impoundment is scheduled for early spring 1979. COST ALLOCATION METHOD: Separable costs - remaining benefits NON- FEDERAL PARTICIPATION AND LOCAL COOPERATION: LOCAL AGENCY: Brazos River Authority *The Brazos River Authority furnished assurances, by resolution of 16 Oct 67, that it will contract for the LAND ACQUISITION: water supply storage as a source of future supply in : Guide Contour : Area (Acres) accordance with provisions of the Water Supply Act of Fee simple 839.0 5,650 1958, as amended. BRA has requested a contract for 10 Fagenent 650 percent of the water supply storage for present use. Total 6,300 Negotiations are in progress. The cost of water supply (Oct 76) is estimated (1 Oct 76) at $8,413,000, exclusive of interest. FLOOD DATA: . Peak Discharge REMARKS: This lake to be built with Granger Lake. Date (cfs) 10 Sep 21 160,000 Dependable yield - 16 cfs 22 -26 Apr 57 155,000 10.3 MGD 4 -6 Oct 59 71,500 6 -11 Jun 44 37,500 (Based on a critical dry period 1947 - 1967) 29 Jun -11 Jul 40 34,500 Sep 36 32,400 Nov 40 30,000 (Georgetown gage) MO JUNCTION 'NORTH FORK RESERVO GEORGETOWN MOE PFLUOERYIILE SCALE SANDOVAL ANDIC���' mwAn JONESTOWN • LIBERTY HILL' ✓t , c CSOUTH \FORK RESERV0I c .1-, � • LEANDER 1 Luke J = M MN - - — — I MN NM M -- MN — I MI M MN m 1( —1 StOr OLD SCNWERTNER Qom ,_:...r....,.. ------- 1 \ _ -• `� B ARTLETT, ' MD m r iR i °wALBURG � \ -\ 1 / - ^'- ,IBS W E I R - / j \ \r r .( P —® \ —t ,.I YOACU� / \_,------. � i\ I WILLIAMSOPI Aluminum Sulphate (Alum) Rapid Mix chani cal vcculator 9 Chemicals) Clarifier with Mechanical Collector Arm' Mu lti - Medi a Grayity•Filter Fork Reservoir North Chemical _ Addition Raw Water Intake Structure Chlorination Pre - Chlorination Raw .ter Line Control & Chemical Building Recycle Sludge i Line Lagoon Supernatant Return Line Post - Chlorination Filter Backwash Pump — — Filter Backwash Li ne Effl uent Pumps Final Effluent Transmission Pump' Station Transmission Line to Round Rocker Waste Sludge Line Sludge Lagoon L _J Lagoon Supernatant Return Pumps EXHIBIT D SCHEMATIC FLOW DIAGRAM Water Treatment Process Haynie & Kallman. Inc. CIVIL ENGINEERING 1 1 1 1 1 1 1 1 1 1 1 1. 1 1 1 1 1 1 1 Air Addition for Mixing Raw Water From Reservoi � c II 11 Chemical Addition (Chlori ne and alum) I Recycle f Sludge 1 Line Access Bridge Mixing Paddle r r r- - - -- i i -- - - -- 1 I 1 Clarifier _ . Rapid t -- - �1 -L _-- ) - - -_ - -- 1 - } Mix 1 - 117- Fied 7 gravity fT�i"�te r I I �___� l _ I_ I I C hamber I I I I I I 11 11 11 11 t— — L t IL } LL t _1L t _id_ t —LL_/ _-LL_ Typical Flocculator Equipment J L_-- - - - - -� 1 t I I I I Mul ti L- - - - - -J L_ - -J I -- Collector Arm Fl occul ator I Drive - -J L. Typical Clarifier Equipment IT t 7 11 } 1 _J II I I Media' `IGravi ty. I Fil _ters l A t. Clarifier Drive Weir Trough C lar i fier filter Inlet / Trough Final Effluent to Ground Storage Waste Sludge Line to Lagoon EXHIBIT E WATER TREATMENT PLANT Equipment Lay -out Haynie & Kaltman, Inc. CIVIL ENGINEERING r Approx. Scale: 1" = 100' r Future Sludge L Lagoons -� r r- - -- - PHASE III 18 Million Gal. Capacity / \ / \ � 3 million \I gal .Ground \� Storage // I --- --1---1---1----'- - PHASE II PHASE I 12 Million Gal. Capacity 6 million Gal. capacity 2 million gal . Ground ) Storage / \..� / PHASE II PHASE III 1 4 ter Treatmellit I Water Treatment i Plant 1 Plant I 111 1 Future control building II Phase III _ —_--J 1 Future control building, Phase II Raw Water Lines from North Fork Reservoi r 0 O 7 Water Treatment Plant C - Chemical Addition and Control Building Existing 16" Raw Water Transmission Line - Phase I Future 24" Raw Water Transmission Line - Phase II Future 30" Raw Water Transmission Line - Phase III EXHIBIT F 36 MGD ULTIMATE CAPACITY WATER TREATMENT PLANT Site Plan at Georgetown Plant Site Haynie & Kallman, Inc. CIVIL ENGINEERING w w 1200 1150 1100 1068' 10'50 1000 w z w z 2 950 w `; 88oi3O0' 0 Natural G ound 900 w w Existing 16" Raw Water Lin 850 Conservation Level 791,06' 800 750 700— e ster Pump S Natur Over Wat didpipe ound E 1 eva 120'x' (18 MGD) r401.74 Sewed, Roc k 1b.ut1ori y DRA 1 ,GRAD l ENT OF•l ; Flood Control Pool (Elev. 834. UU . f t . iri Al .erna tir Tre ment ln :_ Alternate Route Treated Water ganmi Line Exi r.an In osed•Georgetown Water Treatment Plant Srte itiny Raw Water s.rrlission Line and t ake Structure Allowable U.S. Government Waterline Grossing Area Transmission Line To Round Rock Distribution System Ale: 1" 2UOQ' Treated. We ter Transmission Line ,s? North Fork San Gabriel River EXHIBIT c RESERVOIR AREA LAYOUT Haynie all an, Inc, CIVIL ENGINEERING Line 2 • CO rTl eo UTH New 1031 Standpipe 7 7. 7 7 ROUND ROCK Georgetown Water Treatment 'Plant Site co ',Line 4A ine 4B - 33 "i■ TRACT OWNER ACREAGE 1 United States 122 2 United States • 266 3 United States 333 4 United S ta tes 80.70 5 Tophill Corporation 193 Line 5 6 D. B. Wood, et al 1,083 7 D. B. Wood, et al 111 8 D. B. Wood, et al 636 cHA NDLER Ro 9 Jack N. Walker 65.41 10 Jay L. Wolf 412 11 William Thomas Guy, et al 457 12 Florence W. Reavley 50.65 13 L. G. Weir 320 14 Mrs. L. G. Merle Weir 569.98 15 Georgetown Railroad Company 7.85 16 Texas Crushed Stone Corp. 575 17 Texas Crushed Stone Corp. 88.65 18 Texas Crushed Stone Corp. 11.61 19 Westinghouse Electric, Corp. 1,607.09 20 H. C. Carter 80.40 Line 6A 21 C. A. Barton 185 Line 6B Existing 750,000 Gallon Hwy. 81 North Standpipe 11 1 GEORGETOWN.