O-82-952 - 4/8/1982ORDINANCE NO. 502,
AN ORDINANCE AMENDING CHAPTERS 8 AND 3, CODE OF ORDINANCES,
CITY OF ROUND ROCK, TO COMPLY WITH THE STORMWATER DRAINAGE
POLICIES PREVIOUSLY ADOPTED BY THE COUNCIL.
BE IT ORDAINED BY THE COUNCIL OF THE CITY OF ROUND ROCK, TEXAS, THAT
I.
Chapter 8, Section 5.A.(4), Code of Ordinances, City of Round Rock, Texas,
is hereby amended by adding a subsection (q) which said subsection shall read
as follows:
(q) Limits of the 25 year and 100 year flood plain for all waterways
draining 50 acres or more.
II.
Chapter 8, Section 5.B.(1)(c), Code of Ordinances, City of Round Rock,
Texas, is hereby amended to require the following additional information to
be shown on or to accompany the final plat:
Drainage easements to cover the limits of the 25 -year flood plain.
Limits of the 100 -year flood plain.
Minimum finished floor slab elevations, at a minimum of one (1) foot
above the 100 -year flood plain level, for all lots adjacent to or
affected by the flood plain.
A certificate of a registered professional engineer shall be placed on
the face of the plat as follows:
State of Texas
County of Williamson
I, , do hereby certify that the information
contained on this plat complies with the subdivision ordinances
and the stormwater drainage policy adopted by the City of Round
Rock, Texas.
Signature and seal of
registered professional engineer
III.
Chapter 8, Section 6.A.(3)(b), Code of Ordinances, City of Round Rock, Texas,
is hereby amended to read as follows:
(b) One (1) set of reproducible "AS BUILT" plans for each project,
which further contains or has attached thereto a certificate
of a registered professional engineer in substantially the
following form:
State of Texas
County of Williamson
I, , do hereby certify that the
improvements as built and as described herein comply with
the subdivision ordinances and stormwater drainage policy
adopted by the City of Round Rock, Texas.
Signature and seal of
registered professional engineer
IV.
Chapter 8, Section 6.I.(1) Code of Ordinances, City of Round Rock, Texas,
is hereby amended to read as follows:
(1)
Design of all drainage facilities, including inlets, storm
sewers, outfalls, culverts and ditches, shall conform with
the drainage criteria manual and the stormwater drainage
policy, as adopted.
V.
Chapter 8, Section 6.I.(2), Code of Ordinances, City of Round Rock, Texas,
is hereby amended to read as follows:
(2) Design and construction of all drainage facilities shall
conform to the City of Round Rock specifications and follow
the general guidelines below:
(a) Manholes
Manholes (inlets or junction boxes) shall be provided
at all changes in grade or alignment, sewer inter-
sections, and at a maximum of one thousand (1,000') feet
on straight lines. If monolithic, reinforced concrete
sewer lines are used, a manhole shall not be required
where leads from inlets interesect the main sewer.
Design of manholes shall conform to the City of Round
Rock Standard Specifications.
(b) Inlets
Design of inlets shall conform to the City of Round Rock
Standard Specifications.
(c) Pi e
Pipe for storm drains shall be concrete pipe in sizes
as shown on the approved plans. Pipe eighteen (18")
inches or larger in diameter shall be reinforced
concrete pipe (RCP), ASTM C76, Class 3. Where, in
the opinion of the City Engineer, added strength of
pipe is needed for traffic loads over minimum cover
or for excessive height of backfill, concrete pipe
shall be ASTM C14 Extra Strength or ASTM C76, Class
IV or Class V. Pipe shall have a minimum cover of
not less than one (1') foot over the top of pipe.
Monolithic, reinforced concrete sewers may be used
for storm sewers thirty-six (36") inches and larger.
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(d) Major Drainage Ways and Structures
Design of major drainage ways through a subdivision
and major structures, such as box culverts or bridges,
across a major drainage channel, shall be coordinated
with Williamson County Flood Control.
VI
Chapter 3, Section 9.F., Code of Ordinances, City of Round Rock, Texas,
is hereby amended to read as follows:
F. LANDS TO WHICH THIS SECTION APPLIES
This Section shall apply to all land within the corporate limits of
the City of Round Rock, Texas, as may be hereafter extended or altered
in any way.
VII.
Chapter 3, Section 9.0., Code of Ordinances, City of Round Rock, Texas,
is hereby amended by adding subsections (e), (f), and (g) which subsections
shall read as follows:
(e) Site drainage plan, except for single family residential development,
designed in compliance with the drainage criteria manual and the
stormwater drainage policy.
(f) Development involving an increase of 0.5 acres or more of impervious
cover shall provide facilities to prevent any increase in the peak
rate of runoff from a 25 -year frequency storm. Impervious cover is
defined as that man made or constructed coverage of the natural
ground surface with roofs, parking lots, streets, drives, etc. This
coverage shall be calculated as accurately as possible, but in no
case shall it be less than 2500 square feet for a single family
residence or duplex lot. The City Engineer shall have authority to
permit exemptions to the above requirement upon proper application.
Applications for exemption shall be accompanied by certified
engineering data and calculations justifying the request and demon-
strating no adverse impact on all conveyances and property between
the applicant's property and the receiving major stream.
(g) Certificate by a professional engineer that the site drainage plan
and/or minimum slab elevations provided are in compliance with the
drainage policy and criteria of the City of Round Rock.
(h) Following construction, but prior to issuance of a Certificate of
Occupancy by the City, design engineer certification that based
upon his periodic inspection the public works and drainage im-
provements have been constructed in compliance with the City's
requirement.
VIII.
A. All ordinances, parts of ordinances, or resolutions in conflict herewith
are expressly repealed.
B. The invalidity of any section or provision of this ordinance shall not
invalidate other sections or provisions thereof.
(Mark through the following alternative that is not applicable)
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Alternative 1.
By motion duly made, seconded and passed with an affirmative vote of all the
Council members present, the requirement for reading this ordinance on two separate
days was dispensed with.
READ, PASSED, and ADOPTED on first reading this day of
1982.
Alternative 2.
READ and APPROVED on first reading this the1 TN day of
1982.
READ, APPROVED and ADOPTED on second reading this the
ATTEST:
, 1982.
NNE LAND, City Secretary
7
cip
day of
LY L. TONN, Mayor
City of Round Rock, Texas
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