AN ORDINANCE FOR THE CITY OF BELLVILLE, TEXAS, ADOPTING PLANS,
SPECIFICATIONS, AND TECHNICAL REQUIREMENTS APPLICABLE TO SUBDIVISIONS,
COMMERCIAL, AND INDUSTRIAL DEVELOPMENTS WITHIN THE CITY OF BELLVILLE,
TEXAS, AND WITHIN A DISTANCE OF ONE-HALF (1/2) MILE OF THE CORPORATE
LIMITS OF THE CITY OF BELLVILLE, PROVIDING FOR THE SEVERABILITY OF
THE PROVISIONS OF THIS ORDINANCE; PROVIDING FOR AN EFFECTIVE DATE;
AND PROVIDING FOR THE PUBLICATION OF THIS CAPTION AS PROVIDED BY LAW.
BE IT ORDAINED BY THE CITY COUNCIL OF THE CITY OF BELLVILLE,
TEXAS:
This ordinance shall be known, cited, and referred to as “TECHNICAL
MANUAL FOR SUBDIVISIONS, COMMERCIAL, AND INDUSTRIAL DEVELOPMENTS.”
(Ordinance 1419, exhibit 9A, adopted 8/24/10; Ordinance 1675 adopted 6/28/22)
(A) Preliminary
Plat and Related Documents shall include:
(1) Two (2)
originals and five (5) black line or blue line copies of a preliminary
plat covering all of the contiguous land owned or controlled by the
subdivider intended to be developed at any time, even though it is
intended by the developer to file final plats and install improvements
for parts of said tract by sections or units. The preliminary plat
shall be in compliance with all applicable provisions of the subdivision
design regulations.
(2) Three
(3) black line or blue line prints of the preliminary plans for the
furnishing of water, the installation of sanitary sewer facilities,
and provisions for storm sewers and general drainage facilities and
associated calculations. Topographic contours of not more than one-foot
(1') intervals shall be shown.
(3) A letter
of transmittal in duplicate giving the name and address of the owner
or agent and the person or firm who prepared the plat.
(4) In cases
where public streets, alleys or easements are proposed to be platted
across private easements or fee strips, a copy of the instrument establishing
such private easement or fee strip shall be submitted. Where a private
easement has no defined location, an effort shall be made to reach
agreement on a defined easement. (Agreement must be reached before
submission of final plat.)
(B) Preliminary
Plat Specifications -
The Preliminary Plat shall be drawn
on 24" x 36" sheets at a scale not less than 1" = 100'. When more
than one (1) sheet is necessary to accommodate the entire area, an
index sheet at appropriate scale showing the entire area shall be
attached. The plat shall be drawn on mylar film positive accompanied
by ten (10) paper copies. The following shall be shown on the Preliminary
Plat:
(1) Topographic
contours of not more than one-foot (1') intervals.
(2) Title
or name of the subdivision.
(3) Names
and addresses of owners and/or subdividers.
(4) Names
and addresses of persons or firms preparing plat.
(6) Key map
showing location of subdivision in relation to any existing streets
and highways and original survey lines.
(7) The boundary
of the subdivision and accurate dimensions, both linear and angular,
of the boundary.
(8) All existing
utilities, natural water or drainage courses, streets, lots, easements,
and fee strips as to size and location within the subdivision.
(9) Within
200 feet of the boundaries of the subdivision, all existing utilities,
streets, and lots, as to size and location and property lines, survey
lines, and the names of property owners.
(10) All
proposed blocks, lots, alleys, streets, utilities, easements, purposes
thereof, drainage or watercourses, recreation and special use areas,
reserves and their proposed use, proposed land uses, screening devices,
setback lines, proposed dedication of areas for public use other than
streets and easements, and the approximate dimensions of all proposed
items shall be shown. Public facilities and easements included in
any City, County, or regional plan that are included or adjacent to
the land being subdivided shall be shown.
(11) Street
names and lot and block numbers.
(12) Proposed
sectioning, if any.
(13) Area
in subdivision, total number of lots and total area of reserves.
(14) Proposed
location of sediment traps to be constructed for temporary or permanent
purposes in streams and other drainageways.
(15) Boundaries
and locations of any floodplains to be shaded in as found by any governmental
body or state agency acting in accordance with state law or local
ordinance or regulation.
(16) Proposed
uses of the land within the subdivision, including an outline or brief
form of proposed restrictions.
(Ordinance 1419, exhibit 9A, adopted 8/24/10; Ordinance 1675 adopted 6/28/22)
(A) Staking
Plat on Ground -
All final plats must be in full accordance
with the required certification made upon the plat by a registered
land surveyor ascertaining that the plat represents a survey made
by him and that all necessary monuments are accurately and correctly
shown. The surveyor shall place such monuments as required by the
City, including a benchmark as specified by the City Engineer, and
they shall be set at all corners and angle points of the boundaries
of the original tract to be subdivided and at all street intersections,
angle points in street lines and points of curve, and at such intermediate
points as shall be required by the City. Such monuments shall be of
iron rods not less than five-eighths inch (5/8") in diameter and three
feet (3') in length, driven securely into solid earth with the grades
of same being at grade with established sidewalk, or if walk is not
established, flush with natural grade of the earth’s surface.
(B) Final Plat
and Related Documents -
The Final Plat and Related Documents
shall consist of and include the following:
(1) Two (2)
originals and five (5) copies of a final plat meeting all applicable
requirements [of] the subdivision design requirements and the Technical
Manual and certified by a surveyor registered by the State of Texas.
The plat shall be drawn on tracing linen, plastic, or their equivalent
with waterproof black tracing ink or reproduced by photographic process
on linen, plastic, or their equivalent, to scale from an accurate
survey made on the ground, and in all respects shall be neat. The
final plat shall not show zoning information, construction features,
cross-sections, public utility lines, or other structures not involved
in the title covenant.
(2) A current
title report, statement, opinion, title policy, certificate or letter
from a title guaranty company authorized to do business in the State
of Texas, certifying that a search of the appropriate records was
made within the last thirty (30) days covering the land proposed to
be platted and stating an opinion as to current record title ownership
and any encumbrances and encroachments if shown of record.
(3) Tax certificates
shall accompany the plat, indicating that all taxes have been paid.
(4) The owner,
developer, or dedicator of any subdivision plat wherein public streets,
alleys, or easements are shown crossing private easements or fee strips
shall by letter to the City Building Official or City Council assume
responsibility for seeing that any adjustments and protection of existing
pipelines, or other facilities shall be planned and provided for to
the satisfaction of the holder of the private easements of fee strips
and the City Attorney prior to the approval of the plat by the City
Council and filing of the plat for record.
(C) Requirements
Prior to Final Approval -
Before approval of the final
plat by the City Building Official or City Council and before recording
of the plat shall be permitted by the City Building Official or City
Council, compliance with the following requirements shall be made:
(1) Complete
and detailed construction plans and written specifications (indicating
the method of construction and the materials to be used and specifying
all construction equal to or better than hereinafter required and
certified to by a professional engineer registered by the State of
Texas) shall be submitted for:
(a) The
water distribution system showing the size and location of all existing
and proposed water mains, service lines, valves, fire hydrants, and
all other water distribution appurtenances within the proposed subdivision,
also the location and method of connecting the proposed water lines,
water mains, and water services to the City’s existing system.
Refer to applicable provision of the Technical Manual for minimum
requirements.
(b) The
sanitary sewer system showing by plan and profile the size, location
and the gradient of all existing and proposed sanitary trunk lines,
laterals, manholes, cleanouts, lift stations, and services within
the proposed subdivision and the location and method of connecting
the proposed sewer system into the existing sanitary sewer system
or the proposed location, type, capacity and plans of proposed treatment
plant. Refer to applicable provision of the Technical Manual for minimum
requirements.
(c) The
natural gas distribution system showing the size and location of all
existing and proposed gas mains, service lines, valves, regulators
and all other appurtenances with[in] the proposed subdivision; also
the location and method of connection to the City’s existing
system. Refer to applicable provision of the Technical Manual for
minimum requirements.
(d) The
stormwater drainage system showing by plans and profile, the means
and methods of draining the proposed subdivision, showing in detail
all existing and proposed drainage structures and the means and methods
of connecting the proposed drainage system into the City’s existing
drainage system and the means and methods of sediment control shall
be shown. Refer to applicable provision of the Technical Manual for
minimum requirements.
(e) All
proposed bridges or culverts within the proposed subdivision, showing
in detail, by plans and/or profiles, the structural members[,] connectors,
railings, approaches, reinforcing steel and deck, which bridges and
culverts shall, at the City’s option, be constructed of concrete
and/or metal and which culverts shall be a minimum of fifteen inches
(15") inside diameter. Refer to applicable provisions of the Technical
Manual for minimum requirements.
(f) All
existing and proposed streets and alleys within the proposed subdivision,
showing by plans and profiles the width of the rights-of-way; the
widths of the proposed roadways; the gradient of all curblines; the
location and size of all drainage inlets; and the type of pavement.
Refer to applicable provisions of the Technical Manual for minimum
requirements.
(g) All
proposed underground electrical system improvements.
(h) All
existing and proposed streetlights within the proposed subdivision,
showing the location of any and all easements necessary to provide
electricity for said light, with lights to be provided for on every
street intersection within the proposed subdivision, and in such other
locations as may be necessary to properly and evenly light the subdivision
which in no event shall be comprised of a spacing between said lights
of greater than five hundred feet (500').
(All of the above required plans and specifications must be
approved by the City Engineer or an engineer designated by the City
Council, and such approval indicated in writing along with his signature
before the City Council.)
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(2) The owner or developer of the proposed subdivision shall file a performance bond or other form of security as set forth in section
10.02.062(c)(3) approved by the City Council and the City Attorney as to form and surety and sureties on such bond, guaranteeing the completion of such improvements as are required to be constructed by the owner or developer under City policies in effect and as required by this ordinance. Such bond shall be in an amount equal to the estimated cost and amount of the bond shall be approved by the City Engineer. Such bond shall be payable to the City and shall guarantee completion of all required improvements within one (1) year from the date of final approval of such plat. Where for good cause shown to the satisfaction of the City Council, the developer or owner has not completed the required site improvements within one (1) year from the date of the final approval of the plat, the City Council may grant additional time, not to exceed one (1) year, within which to complete said improvement. No such extension shall be granted unless the developer or owner has filed new security in conformance with the conditions applied to the original bond. All bonds shall be kept in the custody of the City Secretary. Bonds shall be released to the principal and/or surety only after all the subdivision requirements have been fulfilled or the money sum of the bond or the amount of the work required yet to be finished has been paid to the City. The City Engineer shall certify to the City Secretary that all the required work has been accepted and completed. In the event that a money settlement is paid the City in lieu of performing the required work, the City Engineer shall certify to the City Secretary that such sum is adequate compensation and that in his opinion the bond should be released.
(3) The following
form shall be used in releasing subdivision bonds and signed by the
City Secretary.
NAME OF PRINCIPAL: __________
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NAME OF SURETY(IES): __________
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NAME OF SUBDIVISION: __________
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This is to certify that all requirements of the City of Bellville,
Texas, concerning the above named subdivision have been met and such
bond is hereby released to the above designated principal and surety(ies).
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__________
City Secretary
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City of Bellville, Texas
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(SEAL)
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(4) The developer
of any plat shall obtain from the holder of any private easement or
fee strip within the plat crossed by proposed street, alley, or other
public easements an instrument granting to the public the use of said
public streets, alleys, or easements over and across said private
easements or fee strips for construction, operation and maintenance
of those public facilities normally using the type of public streets,
alleys, and easements indicated. A signed copy of this instrument
shall be delivered to the City Council and the original shall be filed
for record along with the plat.
(5) The developer
shall furnish the City Council with a letter from the holder of the
private easement or fee strip in question, stating that arrangements
for any required adjustments in pipelines, electrical transmission
lines, or other similar facilities have been made to the satisfaction
of the holder of the easement or fee strip.
(D) Final Plat
Specifications -
The final plat shall include:
(1) General:
The Final Plat shall be prepared and sealed by a registered
professional land surveyor in accordance with the associated Preliminary
Plat. The Final Plat shall have accurate dimensions, both linear and
angular, of all items on the plat. Linear dimensions shall be expressed
in feet and decimals of a foot; angular dimensions may be shown by
bearing. The plat shall be drawn on 24" x 36" sheets at a scale of
not less than 1" = 100', and shall include the following information
as applicable:
(a) The
name of the subdivision, name and addresses of owners and/or subdividers,
name and address of surveyor preparing plat. Legal description of
plat and date of preparation or revision.
(b) North
point and scale and key map.
(c) All
certification statements, dedication restrictions and other inscriptions
as required by this article.
(d) All
lots, blocks, streets, alleys, pipelines, fee strips, watercourses,
easements, reserves and total area, number of lots and number of blocks.
(g) Street
names, lot numbers, block numbers and alphabetical identification
of reserves.
(i) Blocks are to be numbered consecutively within the overall plat as
recorded.
(ii) All lots are to be numbered consecutively within each block. Lot
numbering may be cumulative throughout the subdivision if the numbering
continues from block to block in a uniform manner that has been approved
on an overall preliminary plat.
(iii) Reserves (land to be used for other than residential purposes) are
to be labeled A, B, C, etc., rather than numbered as blocks and lots.
(2) Dimensions
(a) Streets
and Alleys
(i) Complete survey data (P.C., L.R.P.R.C., P.I.) shown on each side
of streets and alleys and/or centerline.
(ii) Length and bearings of all tangents.
(iii) Dimensions from all angle points of curve to an adjacent side lot
line.
(iv) Actual width of all streets and alleys, measured at right angles
or radially where curved.
(b) Lots:
Complete bearings and dimensions for front, rear, and side lot
lines. The following note for side lot lines may be used in lieu of
bearing: “All side lot lines are either perpendicular or radial
to street frontage unless otherwise noted.”
(c) Watercourses
and Easements:
Distance to be provided along the side
lot lines from the front lot line to the point where the side line
crosses the drainage easement line or the high bank of a stream. Traverse
line shall be provided along the edge of all large watercourses on
a convenient location, preferably along a utility easement if paralleling
the drainage easement of a stream.
(d) Pipelines:
Pipelines having no defined easement location or width shall
be tied by dimensions to all adjacent lot and tract corners. If no
agreement can be reached on a defined easement, then building setback
lines shall be shown at a distance of ten feet (10') from the parallel
to the centerline of the pipeline.
(3) Boundaries
-
Ownership or outline of the tract or tracts the plat
is proposed to subdivide shall be shown with very heavy, solid lines.
The boundaries of the plat shall be described with complete and overall
dimensions and bearings and be tied to an original corner of the original
survey of which the subdivision is a part.
(4) Existing
Data -
The location, width, and name of existing streets
and subdivisions or property ownerships and the location and dimensions
of existing lots, easements, pipelines[,] fee strips, survey lines,
building lines, watercourses, or other important information shall
be shown on all sides of the subdivision for a distance of not less
then two hundred feet (200'). The lines of such indication beyond
the plat boundary shall be dashed.
(Ordinance 1419, exhibit 9A, adopted 8/24/10; Ordinance 1675 adopted 6/28/22)
(A) The subdivision
shall conform to the Comprehensive Plan and any separately adopted
part thereof.
(B) The subdivision
layout shall make reasonable provisions for development of adjacent
land.
(C) Name of
Subdivision. Duplication of subdivision names shall be prohibited.
(D) Legal description
of location of subdivision. This description shall be sufficient for
the requirements of title examination.
(E) Name of
owner. If owner is a company or corporation, the name of a responsible
individual such as President or Vice-President must be given.
(F) For preliminary
plat, the name of the person or firm preparing the plat must be shown.
For final plat, name of surveyor certifying the plat must be shown.
(Ordinance 1419, exhibit 9A, adopted 8/24/10; Ordinance 1675 adopted 6/28/22)
(A) General
-
The street pattern of a neighborhood should provide
adequate circulation with[in] the subdivision and yet discourage excessive
through traffic on minor or local streets, the arrangement, character,
extent, width, grade, and locations of all streets shall conform to
the comprehensive plan and shall be considered in their relation to
existing and planned streets, to topographical conditions, to public
safety and convenience, and in their appropriate relation to the proposed
uses of the land to be served by such streets. If any portion of a
collector or major street, as shown in the major Street Plan adopted
as a part of the Comprehensive Plan, traverses any part of the land
being subdivided, that portion of the major or collector street as
planned at the proposed right-of-way width shall be incorporated in
the subdivision plan and shall be dedicated to the appropriate government.
The street layout shall be devised for the most advantageous development
of the entire neighborhood development and shall conform to connecting
streets in land adjacent to the new subdivision. Provision shall be
made within the subdivision to provide street access to adjacent undeveloped
acreage in such a way as to assure adequate circulation for future
development. Dead-end streets and those which do not conform to adjacent
established streets are to be avoided whenever possible. Where a subdivision
abuts or contains an existing or proposed major street (as indicated
in the comprehensive plan or separately adopted part thereof), reverse
frontage lots may be required. When reverse frontage lots are required,
access shall be denied to the major street, and screen planting or
a screening device as defined herein, shall be required along the
rear property line abutting such existing or proposed major street.
Paved alleys shall be provided in commercial and industrial developments,
except where other definite and assured provision is made for service
access, such as off-street loading, unloading and parking consistent
with and adequate for the uses proposed. The street system layout
shall be so designed insofar as practicable to preserve natural features
such as trees, brooks, hilltops, scenic views and other such features.
The street system layout shall provide for the acceptable disposal
of stormwater and provision shall be made by the developer to handle
stormwater to comply with provisions elsewhere in this ordinance.
(B) Right-of-way
Requirements -
All major and secondary streets shall
have a minimum right-of-way width of eighty feet (80'). All residential
streets shall have a minimum right-of-way width of sixty-one feet
(61'), where the plat is inside the city limits and where only single-family
residential lots abut such street. Where proposed streets are extensions
of existing or planned streets designated in the comprehensive plan,
or revisions thereto, having a right-of-way width greater than sixty-one
feet (61'), the proposed streets shall be the same width as the existing
or planned streets. Alleys, where provided, shall not be less than
twenty feet (20') wide. Intersecting alleys shall have corner cut-offs
of at least twenty feet (20') on a side. Alleys with only one (1)
point of access shall have a turnaround with a minimum radius of twenty
feet (20') at their closed ends.
(C) Curves
(1) Secondary
or Major Streets -
Minimum centerline radius of eight
hundred feet (800'). Minimum tangent between points of curvature shall
be fifty feet (50').
(2) Residential
Streets -
Minimum centerline radius of two hundred feet
(200'). Minimum tangent between points of curvature shall be zero
(0).
(D) Offsets
-
Street offsets must be offset a minimum distance of
one hundred twenty-five feet (125') on centerline. Offset distance
shall be indicated on the final plat.
(E) Intersections
(1) All streets
and alleys are to intersect at a ninety-degree (90°) angle with
variations of ten degrees (10°) subject to approval upon evidence
of good cause.
(2) Acute
angle intersections approved by the City Council are to have thirty-foot
(30') radii at acute corners.
(3) Street
or alley intersections with or extending to meet an existing street
or alley will be tied to the existing street or alley on centerline
with dimensions and bearings to show relationship.
(F) Cul-de-Sac
Streets -
Turnarounds are to have a minimum right-of-way
radius of sixty feet (60') with a minimum paved radius of fifty feet
(50').
(G) Provisional
Reserves -
A provisional reserve is not permitted.
(H) Street
Names -
The names of proposed streets shall conform to
the names of existing streets of which they may be or become extensions,
or shall not duplicate or conflict with the recognized name of any
other street located in the area subject to these regulations. The
City shall have the final right to determine acceptability of any
proposed name.
(Ordinance 1419, exhibit 9A, adopted 8/24/10; Ordinance 1675 adopted 6/28/22)
(A) Drainage
-
Where conditions require, there shall be provided a
stormwater drainage easement adequate for the purpose, as determined
by the City Engineer in accordance with the comprehensive plan or
separately adopted part thereof. Where such easement is adjacent to
the lots, tracts, or reserves, the easement shall be noted on the
face of the final plat as follows:
“This easement shall be kept clear of fences, buildings,
plants, and other obstructions to the operation and maintenance of
the drainage facility, and abutting property shall not be permitted
to drain into this easement except by approved means.”
(B) Utilities
(1) Utilities
to be installed in street right-of-way behind the curbs in the front
of lots.
(2) There
also shall be shown on the plat and dedicated for utilities unobstructed
aerial easements and guy wire easements as shall be required by the
City Council.
(3) Easements
as set forth in any applicable city, county, or regional plan for
the location of future sewage or utility facilities shall be provided
and indicated upon the plat.
(Ordinance 1419, exhibit 9A, adopted 8/24/10; Ordinance 1675 adopted 6/28/22)
(A) Block Length
(1) Maximum
block length for a single-family residential development shall be
eight hundred feet (800'), measured along the center of the block,
when the lots are the minimum required area of seven thousand (7,000)
square feet. If the lots are larger than seven thousand (7,000) square
feet minimum, the block length shall be reasonable but shall not exceed
one thousand six hundred feet (1,600').
(2) Maximum
block length along a major thoroughfare, railroad, body of water,
or similar barrier shall be one thousand six hundred feet (1,600'),
except under special conditions and upon approval by the City Council.
(B) Lots
(1) General
-
The lot design should provide for lots of adequate
width, depth, and shape to provide open area, to eliminate overcrowding,
and to be appropriate for the location of the subdivision and for
the type of development and use contemplated. Lots should have the
side lot lines at right angles to the streets on which the lot faces
of [or] radial to curved street lines.
(2) Rear
and Side Driveway Access -
Rear and side driveway access
to major thoroughfare or freeways shall be prohibited.
(3) Minimum
Requirements for Residential Lots
(a) Single-family
and Duplexes
(i) Minimum Width at Building Setback Lines -
Sixty feet
(60'). (At a distance not greater than twenty-five feet (25') from
the front lot line.)
(ii) Minimum Width at Front Lot Line -
Forty feet (40').
(iii) Minimum Area of Lots Within City Limits -
Seven Thousand
Five Hundred (7,500) square feet.
(iv) Corner lots siding on minor streets shall have a minimum width at
the building setback line of not less than seventy feet (70').
(v) Corner lots siding on major thoroughfare or freeway shall have a
minimum width at the building setback line of not less than seventy-five
feet (75').
(vi) Minimum depth of conventional lots shall be one hundred fifteen feet
(115') except lots facing or backing on a major thoroughfare or freeway
shall be not less than one hundred and twenty-five feet (125') deep.
The minimum depth of lots with frontage on cul-de-sacs shall be one
hundred feet (100').
(vii) Septic Tanks -
If feasible in the opinion of the City,
a subdivision outside the City must be connected to the City sanitary
sewer system. If a residential subdivision outside the city limits
proposed to contain only single-family or duplex dwelling units is
not to be served by a public sanitary sewer system and septic tanks
are to be used, lot sizes shall be adequate to accommodate the size
of drainfield as necessary because of soil type to effectively absorb
the effluent without creating a health hazard or a nuisance as governed
by Austin County requirements.
(Ordinance 1419, exhibit 9A, adopted 8/24/10; Ordinance 1675 adopted 6/28/22)
(A) Only one
(1) townhouse may be constructed per lot.
(B) Minimum
Width -
Twenty-four feet (24'), except the end unit or
unit which occupies a corner lot shall provide an additional ten feet
(10') for side yard.
(C) Minimum
Area -
Two thousand (2,000) square feet.
(D) Minimum
Number of Lots in a Townhouse Project -
Three (3).
(E) A townhouse
project shall have not less than five hundred (500) square feet of
open space per dwelling unit in addition to lots and parking areas
for recreational and/or yard use.
(Ordinance 1419, exhibit 9A, adopted 8/24/10)
(A) Definitions
Patio Home.
The term “patio home” shall mean a single-family
development construction on a single lot, with the building line (including
drip line) of one (1) side of the structure being tangential to the
property line and allowing for yard space at the front, one (1) side
and at the back of the structure.
Patio Home Subdivision.
The term “patio home subdivision” shall apply
to those developments in which it is proposed to partition land into
individual lots, construct patio homes which may be individually owned,
and where such housing is separated by a minimum distance as specified
herein.
(B) Specifications.
Patio homes (zero lot line):
(1) Minimum
Site Area.
The minimum area for patio home development
shall be not less than fourteen thousand (14,000) square feet.
(2) Size
of Yards
(a) Front
Yard.
There shall be a front yard having a depth of not
less than twenty feet (20').
(b) Side
Yard.
A side yard of ten feet (10') shall be maintained
adjacent to one property line, except where the side yard is adjacent
to a plat boundary that is contiguous to a standard single-family
subdivision, said side yard shall be ten feet (10'). Adjacent to public
streets, a side yard of not less than fifteen feet (15') is required.
(c) Rear
Yard.
A rear yard of twenty feet (20') shall be maintained.
There shall be a rear yard of not less than twenty feet (20') adjacent
to all major streets.
(3) Size
of Lots
(a) Lot
Area.
No building shall be constructed on any lot less
than thirty-five hundred (3,500) square feet.
(b) Lot
Width.
The width of a lot shall not be less than forty
feet (40') at the front building line nor shall the average width
be less than forty feet (40').
(c) Lot
Depth.
The average depth of a lot shall not be less than
fifty feet (50').
(4) Openings
Prohibited.
Openings are prohibited on the zero (0) lot
line side. The wall of the dwelling located on the lot line shall
have no windows, doors, air conditioning units or other type of opening.
Atriums or courts shall be permitted on the zero (0) lot line side
when the court or atrium is enclosed by three (3) walls of the dwelling
unit and a solid wall of at least eight feet (8') in height is provided
on the zero (0) lot line. Said wall shall be constructed of the same
material as exterior walls of the unit.
(5) Each
deed whereby a patio home is conveyed must contain a limited license
or easement that will permit the owners of the adjacent property to
enter onto the property at reasonable times and upon reasonable notice
to maintain or repair the structure adjacent to the zero (0) lot line.
(Ordinance 1419, exhibit 9A, adopted 8/24/10)
(A) No lot
to be used for multifamily or apartment purposes shall contain an
area of less than seven thousand (7,000) square feet plus an additional
one thousand five hundred (1,500) square feet for each dwelling unit
in excess of two (2) dwelling units within structures to be constructed
or occupied upon such a lot. Each plat shall contain a restriction
in accordance with the above as approved by the City Attorney.
(B) Each lot
containing a multifamily complex or apartment must be served by an
approved sanitary sewer.
(Ordinance 1419, exhibit 9A, adopted 8/24/10)
(A) Must be
served by an approved sanitary sewer.
(B) Minimum
Width at Front Lot Line -
Twenty-five feet (25').
(C) Lots may
be of various sizes and widths but in no event may the minimum area
of an individual lot be less than three thousand (3,000) square feet.
(D) Minimum
Number of Lots in a Cluster Development -
Twenty (20).
(E) For every
square foot of each lot less than seven thousand (7,000) square feet
in the subdivision there shall be designated for public open space
purposes the same quantity of square feet.
(F) No residential
lot may be designated other than for single-family residential purposes.
(G) The average
density of population per acre shall not be greater for the entire
subdivision than that for single-family and duplexes using one (1)
family per seven thousand (7,000) square feet as standard criteria.
(H) Within
all cluster developments platted within a forest or adjacent to a
lake, stream, bayou, or beach, the area that shall be dedicated for
public open space purposes shall be an area within the forest or adjacent
to the lake, stream, bayou, bay or beach.
(Ordinance 1419, exhibit 9A, adopted 8/24/10)
(A) All residential
condominium projects or condominium projects containing residential
uses as well as a combination of any other use or uses must be served
by a sanitary sewer system.
(B) Only one
(1) condominium regime may be established per lot as recorded by the “master
deed,” “master lease,” or “declaration”
as found in the appropriate records of the County.
(C) The minimum
size of the master lot from which all the residential units and other
sub-units are to be conveyed shall be the sum of the totals of the
minimum square feet of each type residential unit specified in this
section multiplied by the respective number of units for that category.
For each use other than residential wherein there is no minimum lot
area provided by this ordinance, the City Council shall add a minimum
number of square feet to be consistent with the fire ordinance, or
any parking regulations established by the City and shall insure that
there is proper buffering if necessary between contrasting uses in
the condominium.
(D) No condominium
lot shall be platted in a floodplain.
(Ordinance 1419, exhibit 9A, adopted 8/24/10)
For subdivisions for single-family and two (2) family dwellings,
building setback lines adjacent to streets shall be shown and labeled
on all plats, both preliminary and final. For such dwellings and all
residential lots, the building setback line shall not be less than
thirty-five feet (35') from a front lot line and twenty-five feet
(25') from a side lot line that is also a street right-of-way line
on a corner lot. Building setback lines in single-family and two-family
dwelling subdivisions, and all residential lots except as specifically
provided elsewhere from side lot lines, except for corner lots, as
set forth above, shall be not less than ten feet (10') from a side
lot line, and in the case of subdivisions shall be so noted on the
plat. Building setback lines for apartment or multifamily developments
shall be not less than fifteen feet (15') from any side or rear lot
lines. Residential dwellings shall be set back a minimum of twenty-five
feet (25') from the rear property line. Accessory buildings shall
be a minimum of ten feet (10') from the rear property line. Such shall
be noted on all plats as a condition to the use of any portion of
the property for multifamily or apartment purposes. Building setback
lines for lots in cluster development shall not be less than twenty-five
feet (25') from any street. If proposed subdivision is a townhouse
development where community sidewalks are to connect adjoining structures
on separate lots, no side yard is required. The minimum setback line
for a townhouse lot shall be fifteen feet (15'). Building lines shall
also comply with all other ordinances adopted by the City of Bellville.
(Ordinance 1419, exhibit 9A, adopted 8/24/10; Ordinance 1675 adopted 6/28/22)
(A) Surveyor’s
Certification
This is to certify that I, __________, a licensed surveyor of
the State of Texas, have platted the above subdivision from an actual
survey on the ground; and that all block corners, angle points and
points of curve are properly marked with five-eighth-inch (5/8") iron
rods, three feet (3') long set with the head flush with the ground
or sidewalks; that this plat correctly represents that survey made
by me.
|
__________________
Signature
|
__________________
Registration Number
|
(B) Plat Dedication
and Certification
The following form for dedications and certifications shall
be utilized on the final plat of subdivisions or resubdivisions:
STATE OF TEXAS
|
COUNTY OF AUSTIN
|
I (or we), (name(s) of owner(s) or in the case of corporations,
name of “president and secretary” respectively) of (name
of “company”) owner (or owners) of the property subdivided
in the above and foregoing map of the (name of subdivision), do hereby
make subdivision of said property (in case of corporation, use words
for and on behalf of said/name of company), according to the lines,
streets, alleys, parks, and easements therein shown, and designate
said subdivision as (name of subdivision) in the _____ Survey, Austin
County, Texas; and (in case of corporation, use words on behalf of
said/name of company) dedicate to public use, as such, the streets,
alleys, parks and easements shown thereon forever; and do hereby waive
any claims for damages occasioned by the establishing of grades as
approved for the streets and alleys dedicated, or occasioned by the
alteration of the surface of any portion of streets or alleys to conform
to such grades and do hereby bind myself (or ourselves), my (or our)
such heirs and assigns to warrant and forever defend the title to
the land so dedicated. There is also dedicated for utilities an unobstructed
easement _____ (_____) feet wide from a plane _____ (_____) feet above
ground upward located as shown hereon. We have also complied with
all regulations hereto before adopted by the Commissioner’s
Court of Austin County, Texas.
|
(C) Mortgagee’s
Statement
The following paragraph is to be used where there is a lien
against the property (or a separate instrument may be filed):
I, (or we), (name of mortgagees), owners(s) and holders(s) of
a lien(s) upon said property do hereby ratify and confirm said subdivision
and dedication and do hereby in all things subordinate to said subdivision
and dedication the lien(s) against said landowner and held by me (us).
Signature(s) of lienholder(s) to appear below that of owner’s
and to be duly acknowledged.
|
(D) Board
of Aldermen’s Certification
This is to certify that the Board of Aldermen of the City of
Bellville, Texas, has approved this plat and subdivision of (name
of Subdivider) as shown herein.
|
IN TESTIMONY WHEREOF, in witness the official signatures of
the Mayor, Aldermen and City Secretary of the City of Bellville, Texas
this the _____ day of _____, 20_____.
|
__________________
Mayor
|
__________________
Alderman
|
__________________
Alderman
|
__________________
Alderman
|
__________________
Alderman
|
__________________
Alderman
|
__________________
City Secretary
|
(E) County
Clerk’s Certification
STATE OF TEXAS
|
COUNTY OF AUSTIN
|
I, (name of County Clerk), Clerk of the County Court of Austin
County, Texas, do hereby certify that the written instrument with
its certificate of authentication was filed for registration in my
office on _____, 20_____, at _____ o’clock, _____m., Volume
_____, Page _____, Records of said County.
|
WITNESS MY HAND AND SEAL OF OFFICE, at _____ the day and date
last above written.
|
__________________
(Name of Clerk)
|
Clerk, County Court
|
Austin County, Texas
|
By:__________________
|
Deputy
|
(Ordinance 1419, exhibit 9A, adopted 8/24/10; Ordinance 1675 adopted 6/28/22)
(A) Before
beginning any construction of the improvements authorized in this
Article on proposed roadways, public utilities, or drainage facilities,
or structures pertaining to any subdivision coming under the provisions
of this ordinance and within the city limits, complete plans and specifications
for such improvements shall have first been completely approved by
the Engineer or his designated engineer as meeting the City’s
standards in connection with the approval of a final plat of the proposed
subdivision by the City Council.
(B) The City
Engineer or his duly authorized representative shall from time to
time inspect the construction of all utility facilities and streets
in the subdivision during the course of construction to see that the
same comply with the standards governing the same. The inspection
fee shall be paid by the subdivider. In this regard, free access to
the subdivision shall be accorded the City Engineer and his duly authorized
representative by the subdivider, his agents, and employees. Inspection
by the City Engineer, or failure of the City Engineer to inspect construction
as required herein shall not in any way impair or diminish the obligation
of the subdivider to install improvements in the subdivision in accordance
with plans and specifications therefor as approved by the City Engineer
and the City Council and in accordance with the City’s or County’s
standards.
(C) After all
required improvements have been completed the owner or subdivider
of the subdivision shall file with the City Secretary within thirty
(30) days after completion of all required improvements one (1) set
of record drawings of all underground utilities and street improvements
that have been constructed.
(D) In the
event exigencies of construction necessitate changes in plans and
specifications, approval of the changes must be made by the City Engineer
prior to making any revisions in the construction.
(Ordinance 1419, exhibit 9A, adopted 8/24/10; Ordinance 1675 adopted 6/28/22)
The following minimum standards apply to public streets:
(A) Type.
Asphaltic or reinforced concrete surface with concrete curb
and gutter.
(B) Minimum
Pavement Width
(1) Major
Streets -
Forty-four feet (44')
(2) Secondary
Streets -
Thirty-eight feet (38')
(3) Residential
Streets -
Forty feet (40').
(C) Cross-Section
-
The standard cross-section for a residential street
is thirty feet (30') wide by five and one-half inches (5-1/2") thick
for concrete or a six-inch (6") minimum thickness base with a one
and one-half [inch] (1-1/2") minimum thickness HMAC pavement. The
standard cross-section for a collector street is thirty-nine feet
(39') wide by six inches (6") thick for concrete or an eight-inch
(8") minimum thickness base with a two-inch (2") minimum thickness
HMAC pavement. The standard cross-section for a thoroughfare street
is forty-four feet (44') wide by seven inches (7") thick for concrete
or a ten-inch (10") minimum thickness base and a two-inch (2") HMAC
pavement. At intersections, curb return radius shall be twenty feet
(20'); cul-de-sacs thirty-five feet (35').
(D) Concrete
(1) Reinforcing
Steel
(a) Material -
Open hearth new billet steel.
(b) Yield Strength -
Sixty thousand (60,000) pounds per
square inch, minimum.
(c) Splices -
Twenty-four (24) bar diameters.
(d) Bar Size and Spacing -
No. 3 bars at eighteen-inch (18")
centers, each way.
(e) Bar Support -
Metal or plastic “chairs”
shall be used to hold bars in position during placement of concrete.
(2) Concrete
Mixture
(a) Compressive Strength -
Two thousand four hundred (2,400)
pounds per square inch minimum at seven (7) days and three thousand
five hundred (3,500) pounds per square inch minimum at twenty-eight
(28) days as determined in accordance with American Society of Testing
and Materials (ASTM) C39 or C109.
(b) Slump -
Four inches (4") maximum as determined in accordance
with ASTM C143 (most current edition).
(c) Cement Factor -
Five and one half (5.5) bags per cubic
yard, minimum.
(d) Cement -
Type I (normal) Portland cement, or with City
Engineer’s approval, Type III (high early strength). No fly
ash shall be allowed in lieu of cement.
(3) Aggregate
-
Coarse and fine aggregate shall meet the requirements
of Texas Department of Transportation (TxDOT) Standard Specification “Item
360” for concrete pavement.
(4) Jointing
(a) Depth of Contraction Joints -
One-fourth (1/4) of slab
thickness.
(b) Longitudinal Spacing.
Expansion Joints - Sixty feet
(60') (maximum). Contraction Joints - Twenty feet (20') (maximum).
(c) Transverse Spacing -
Twenty feet (20') (maximum).
(d) Expansion Joints -
At intersections.
(e) Joint Filler Material -
Pre-formed expansion joint filler
of the bituminous type which conforms to ASTM D 1751, 3/4 inch thickness.
(f) Joint Seal -
Joint sealing material shall conform to
the requirements of ASTM C-920, Type S, Grade PorNS.
(5) Curing
-
Curing method shall retain at least ninety-seven percent
(97%) of moisture at twenty-four (24) hours, at least ninety-five
percent (95%) at three (3) days, and at least ninety-one percent (91%)
at seven (7) days. (American Society of Testing and Materials Procedure
C-5.)
(6) Tests
-
Compression Strength - A test set, consisting of at
least three (3) cylinders, shall be cast during each placement. The
cylinders shall be cast at a rate of one (1) set for every fifty (50)
cubic yards of concrete if total concrete placement is less than two
hundred (200) cubic yards. If the total concrete placement is greater
than two hundred (200) cubic yards, then the rate should be one set
for every one hundred (100) cubic yards of concrete placed. At least
one (1) set shall be cast during each placement day.
(7) Placement
-
Concrete shall not be placed on frozen subgrade; when
air temperature is thirty-eight degrees (38°) Fahrenheit or below;
when air temperature is below forty-two degrees (42°) Fahrenheit
and declining; when finishing cannot be completed during natural daylight.
(E) Asphaltic
Pavement
(1) Curb
and Gutter
(a) Material -
Reinforced concrete as specified in this
section.
(b) Width -
Twenty-four inches (24") overall.
(c) Tests -
Same as Subsection (D)(6) of this section.
(2) Base
(a) Thickness -
Six inches (6") after final compaction.
(b) Material and Construction -
Material shall be crushed
stone meeting TxDOT Standard Specification “Item 247”
for Type A, Grade 2. Compaction of the base materials shall be a minimum
density of ninety-seven percent (97%) of the maximum dry density as
determined by the Modified Proctor density (ASTM D1557) (most current
edition) at a moisture content within ± two percent (2%) of
optimum.
(c) Tests -
Material - The City Engineer may require laboratory
testing of the proposed material before and/or during construction
to determine that it meets the applicable specifications. Compaction
and Depth: Tests at two hundred (200) linear foot intervals, or closer
where requested by the City Engineer.
(3) Surface
Course
(a) Material -
TxDOT Standard Specifications “Item
340” for hot mix asphaltic concrete pavement, Type D, including
prime and tack coat. An asphalt mix design shall be submitted to the
City Engineer for approval prior to placement.
(b) Minimum Thickness -
One and one-half inches (1-1/2")
after final compaction.
(c) Density -
A compaction density of ninety-two (92) to
ninety-six (96) percent of the maximum theoretical density as determined
in accordance with ASTM D1559 (most current edition).
(d) Tests -
The City Engineer may require the following
tests: Material laboratory tests before and/or during construction;
in place density.
(4) Subgrade
(a) Rolling Machinery -
All subgrade shall be rolled.
(b) Density Required -
At least ninety-five percent (95%)
of the maximum dry density as determined by the Modified Proctor density
(ASTM D1557) (most current edition) at a moisture content between
-1% and +2% of optimum.
(c) Density Tests Frequency -
At two hundred (200) linear
feet intervals or closer when requested by the City Engineer.
(d) Lime Stabilization -
Required when plasticity index
(PI) of subgrade soil exceeds 20.0. The optimum percentage of lime
to be added shall be determined based on TEX-121-E laboratory tests.
Lime and required water shall be thoroughly mixed and blended with
subgrade by an approved pulverizing mixer to a minimum depth of six
(6) inches. All lime stabilization shall be performed in accordance
with TxDOT Item 260.
(e) Cement Stabilization -
Required when plasticity index
(PI) is less than five (5), “spongy” or wet soils. Five
percent (5%) by weight cement shall be thoroughly mixed and blended
with subgrade by an approved pulverizing mixer to a minimum depth
of 6 inches.
(f) Subgrade
shall not be allowed to dry before concrete or base is placed, nor
shall concrete or base be placed on frozen subgrade. Apply seal or
additional course within fourteen (14) days of final compaction.
(Ordinance 1419, exhibit 9A, adopted 8/24/10; Ordinance 1675 adopted 6/28/22)
The following minimum standards apply to water system extensions
within the City of Bellville.
(A) Main Lines
(1) Minimum
Diameter -
Six inches (6").
(2) Depth
-
Three feet (3') six inches (6") of cover below final
grade.
(3) Material
Type -
C-900 PVC[.] Pressure rating: One hundred fifty
(150) pounds per square inch. Field tests shall be in accordance with
American Water Works Association requirements. Pipe shall be manufactured
within the United States.
(4) Location
-
Mains shall be looped with no dead-ends serving more
than four (4) lots.
(5) Trace
Wire -
Twelve (12) gauge thermoplastic insulated solid,
direct burial conductive copper wire securely bonded together at all
joints and pipe intersections and accessible at all valve boxes and
services. Wire connectors to be 3M DBR or approved equal and shall
be watertight and provide electrical continuity.
(B) Valves
(1) Locations
-
At tees: Two (2) valves. At crosses: Three (3) valves.
At each connection to existing water system: One (1) valve.
(2) Type
-
Nonrising stem, O-ring seals, Mueller CCW opening,
M.J.
(3) Valve
Boxes -
Adjustable height valve boxes shall be cast iron
encased with a four-inch (4") thick by twenty-four-inch (24") square
reinforced concrete pad.
(C) Fire Hydrants
(1) Locations
-
Single-family residential areas: five-hundred-foot
(500') intervals approximately, and at the end of each cul-de-sac.
Multifamily or commercial, including reserves: three-hundred-foot
(300') intervals.
(2) Type
-
Mueller Improved, three (3) way with threads matching
City’s requirements, CCW opening, M.J.
(D) Fittings
(1) Material
- Ductile iron, cement lined, concrete blocked, M.J.
(2) Pressure
Rating -
Two hundred fifty (250) pounds per square inch
(minimum).
(E) Services
(1) Corporation
Stop -
Mueller, Ford or approved equal.
(2) Combination
Curb Stop and Meter Yoke (Line Setter) with Lock Wing -
Ford LSV41-233 or equal, in approved inverted plastic meter box.
(3) Pipe
Material -
Type K soft copper.
(4) Size
-
Single Service: Three-fourths inch (3/4") diameter.
Double Service: One inch (1") diameter.
(5) Marking
-
“Record Drawing” plans required to show
location of services. End of services not connected to an existing
structure shall be marked with six-foot (6') long (three-foot (3')
buried) heavy duty T post painted blue. Also, where a service crosses
a proposed curb, the curb shall be marked with a “W” inscribed
in the top of the curb.
(F) Flush
Valves
(1) Provide
a two-inch (2") flush valve at the end of all dead-end main water
lines.
(2) Construct
flush valves in accordance with the detail contained on the City’s
Standard Water Details sheet.
(G) Embedment
-
Pipe shall be embedded in bank sand. Embedment shall
extend a minimum of four inches (4") below the pipe; a minimum of
eight inches (8") on each side of the pipe and a minimum of twelve
inches (12") above the pipe. The embedment material shall be compacted
to a minimum of eighty-five percent (85%) of maximum density as defined
by Standard Proctor (ASTM D698) testing procedures.
(H) Backfill
(1) Under
Asphalt Streets -
One and one-half (1.5) sack per cubic
yard (minimum) cement stabilized sand compacted to a minimum of ninety-five
percent (95%) of Standard Proctor (ASTM D698) density at a moisture
content within three percent (3%) of optimum.
(2) Other
Locations -
Sandy soil must be water jetted; other soil
may be compacted using mechanical compacters.
(I) Tests.
Satisfactory bacteriological and pressure tests in accordance
with the Texas Commission on Environmental Quality’s (TCEQ)
requirements are required before acceptance by the City.
(Ordinance 1419, exhibit 9A, adopted 8/24/10)
All residences must be connected to the City’s central
sanitary sewer system. The following minimum standards apply to the
sanitary sewer extensions within the City of Bellville.
(A) Main Lines
(1) Minimum
Diameter -
Six inches (6").
(2) Minimum
Depth -
Four feet (4') zero inches (0").
(3) Material
Pipe -
PVC SDR 26 sewer pipe, ASTM D3034 (minimum), PVC
SDR 26 CL 160, ASTM D2241 or Ductile Iron Pipe as per TCEQ requirements.
(4) Trace
Wire -
Twelve (12) gauge thermoplastic insulated solid,
direct burial conductive copper wire securely bonded together at all
joints and pipe intersections for force mains only. Wire connectors
to be 3M DBR or approved equal and shall be watertight and provide
electrical continuity
(B) Manholes
(1) Size
-
Four feet (4') zero inches (0") (minimum).
(2) Spacing
-
Five hundred feet (500') maximum.
(3) Material
-
Precast concrete with interior coating thickness of
10 mil coal tar epoxy or traffic rated fiberglass (one-half-inch (1/2")
minimum wall thickness) as manufactured by Fluid Containment, Inc.
or approved equal.
(4) Wall
Thickness -
Six inches (6") (minimum) for concrete manholes.
(C) Services
(1) Pipe
Diameter -
Four inches (4").
(2) Material
-
ASTM D3034 SDR26 PVC.
(3) Fittings
Required -
Wye, bend, and plug.
(4) Service
Cleanout -
A four-inch (4") diameter two (2) way cleanout
is required at the right-of-way line.
(5) Marking
-
“Record Drawing” plans required to show
location of services. End of services not connected to an existing
structure shall be marked with six-foot (6') long (three-foot (3')
buried) heavy duty T post painted green. Also where service crosses
a proposed curb, the curb shall be marked with a “Y”.
(D) Cleanouts
-
A six-inch (6") diameter with cleanout boot shall be
provided at the upper end of sanitary sewer lines.
(E) Lift Station
-
If a lift station is required to serve the subdivision,
the lift station shall be designed in accordance with the City of
Bellville requirements.
(F) Embedment
-
Pipe shall be embedded in bank sand. Embedment shall
extend a minimum of four inches (4") below the pipe; a minimum of
eight inches (8") on each side of the pipe and a minimum of twelve
inches (12") above the pipe. The embedment material shall be compacted
to a minimum of eighty-five percent (85%) of maximum density as defined
by Standard Proctor (ASTM D698) testing procedures.
(G) Backfill.
Backfill used in connection with Sanitary Sewer Systems shall
be the same quality as specified for use in connection with water
systems.
(H) Tests.
Testing of all wastewater improvements in accordance with TCEQ
requirements are required before acceptance by the City.
(Ordinance 1419, exhibit 9A, adopted 8/24/10)
(A) Design
requirements for drainage criteria administered by the City of Bellville
are intended to provide protection from structural flooding from a
one hundred (100) year storm event. This is accomplished through application
of various drainage enhancements, such as storm sewers, roadside ditches,
open channels, detention and overland (sheet) runoff. The combined
system is intended to prevent structural flooding from extreme events
up to a one hundred (100) year storm. Recognizing that each site has
unique differences that can enhance the opportunity to provide proper
drainage, the intent of these criteria is to specify minimum requirements
that can be modified provided that the objective for drainage standards
is maintained. The developer shall design and construct downstream
drainage improvements or a detention system to protect downstream
property owners from any change in stormwater runoff.
(1) Street
Drainage:
Street ponding of short duration is anticipated
and designed to contribute to the overall drainage capability of the
system. Storm sewers and roadside ditch conduits are designed as a
balance of capacity and economics. These conduits are designed to
convey less intense, more frequent rainfalls with the intent of allowing
for traffic movement during these events. When rainfall events exceed
the capacity of the storm sewer system, the additional runoff is intended
to be stored or conveyed overland in a manner that reduces the threat
of flooding to structures.
(2) Flood
Control:
The City of Bellville is a participant in the
National Flood Insurance Program. The flood insurance program makes
insurance available at low cost by providing measures that reduce
the likelihood of structural flooding.
(3) Relationship
to the Platting Process:
Approval of storm drainage is
a part of the review process for planning and platting of a new development.
(4) Conflicting
Provisions:
The specifications set forth in this manual
shall control over any publication of any standardized reference.
In the event of a conflict, the conflict shall be resolved by the
City Engineer.
(B) References
(1) Fort
Bend County Drainage Criteria Manual.
(2) TxDOT
Hydraulics Manual, most current edition.
(C) Definitions
(1) Conduit -
Any open or closed device for conveying
flowing water.
(2) Drainage Area Map -
Area map of watershed which
is subdivided to show each area served by each subsystem.
(3) Hydraulic Grade Line -
A line representing
the pressure head available at any given point within the drainage
system.
(4) Redevelopment -
A change in land use that alters
the impervious cover from one (1) type of development to either the
same or another type, and takes advantage of the existing infrastructure
in place as a drainage outlet.
(5) Infill Development -
Development of open tracts
of land in areas where the storm drainage infrastructure is already
in place and takes advantage of the existing infrastructure as a drainage
outlet.
(6) Rational Formula -
A method for calculating
the peak runoff for a storm drain system using the following equation
for runoff: Q = I * (CA)
Where:
|
C = watershed coefficient
|
|
A = area (acres)
|
|
I = rainfall intensity (inches per hour)
|
(7) Design Storm Event -
Rainfall intensity upon
which the drainage facility will be sized.
(8) Rainfall Frequency -
Probability of a rainfall
event of defined characteristics occurring in any given year. Information
of rainfall frequency is published by the National Weather Service.
For the purpose of storm drainage design, the following frequencies
are applicable:
(a) Five (5) Year Frequency -
Rainfall
intensity having a twenty percent (20%) probability of occurrence
in any given year, or nominally likely to occur once every five (5)
years.
(b) Ten (10) Year Frequency -
Rainfall
intensity having a ten percent (10%) probability of occurrence in
any given year, or nominally likely to occur once every ten (10) years.
(c) Twenty-Five (25) Year Frequency -
Rainfall
intensity having a four percent (4%) probability of occurrence in
any given year, or nominally likely to occur once every twenty-five
(25) years.
(d) One Hundred (100) Year Frequency -
Rainfall intensity having a one percent (1%) probability of occurrence
in any given year, or nominally likely to occur once every one hundred
(100) years.
(9) Sheet Flow -
Overland storm runoff that is
not conveyed in a defined conduit and is typically in excess of the
capacity of the conduit.
(10) Manning’s Equation:
V = (K/n)R2/3 Sf
1/2
Where:
|
K = 1.49 for English units, 1.00 for metric units
|
|
V = Velocity (f./sec or m/sec)
|
|
R = Hydraulic radius (ft. or m) (area/wetted perimeter)
|
|
Sf = Friction slope (headloss/length)
|
|
n = 0.013 for concrete pipes, 0.024 for CMP pipes
|
(11) Continuity Equation:
Q = VA
Where:
|
Q = Discharge (cfs or cms),
|
|
V = Velocity (ft/sec or m/sec)
|
|
A = Cross-sectional area of conduit (square feet or square meters)
|
(12) FEMA -
Federal Emergency Management Agency.
(D) Design
Requirements
(1) Design
of drainage facilities shall meet requirement of the Bellville Development
Code and Standard Specifications and Standard Details provided in
this manual.
(2) Determination
of Runoff
(a) Design Storm Events
(i) Rainfall Duration
1. For design purposes, the rainfall duration for drainage areas less
than two hundred (200) acres will be no less than three (3) hours
in duration.
2. For design purposes, the rainfall duration for drainage areas more
than two hundred (200) acres will be no less than six (6) hours of
duration.
(ii) Intensity - Duration Curves.
The Intensity-Duration-Frequency
(IDF) formula contained within the TxDOT Hydraulics Manual shall be
used for storm sewer and roadside ditch design in the City of Bellville
and its ETJ.
(b) Application of Runoff Calculation Models
(i) Stormwater runoff computations for all drainage areas shall be based
upon ultimate watershed conditions with the following storm frequencies
shall be used in designing:
1. Rational Method:
The rational method will be used for
design on storm sewered areas up to two hundred (200) acres in size
and for areas served by roadside ditches.
2. Rainfall Runoff Modeling:
Rainfall runoff modeling will
be applied to areas greater than two hundred (200) acres in size.
Rainfall runoff modeling shall be used for modeling of storm sewered
areas greater than two hundred (200) acres provided the model considers
the storage and ponding in streets. If the modeling is associated
with establishing a floodprone area for purposes of a FEMA submittal,
the models must be acceptable to that agency. Other models that may
be used are Soil Conservation Service (SCS) Unit Hydrography techniques.
(ii) Use of the WinStorm computer program is required for calculating
the capacity of inlets and storm drain systems. The program is available
at no cost through TxDOT’s website. The complete report the
WinStorm program can generate shall be submitted as part of the drainage
report. In addition, both an analysis layout and an electronic medium
(diskette or CD) of the analysis shall be provided.
(c) Coefficients for the Rational Method
(i) Runoff Coefficients:
The “C” values shown
in the table below shall be used in design to represent ultimate watershed
development conditions. When ultimate development conditions or undeveloped
property cannot be verified, a standard runoff coefficient of 0.70
may be used.
1. A drainage area under investigation may consist of several varied
drainage surfaces; therefore, a weighted average coefficient in accordance
with the respective areas shall be utilized.
Land Use
|
Value of C
|
---|
Residential (Single-Family) Areas
|
|
Lots More Than 1/2 Acre
|
0.35
|
Lots 1/4 -1/2 Acre
|
0.45
|
Lots Less Than 1/4 Acre
|
0.55
|
Multifamily Areas
|
|
Less than 20 Service Units/Acre
|
0.65
|
20 Service Units/Acre or Greater
|
0.80
|
Business Areas
|
0.80
|
Shopping Centers
|
0.95
|
Industrial Areas
|
0.70
|
Railroad Yard Areas
|
0.30
|
Parks/Open Space
|
0.30
|
2. Alternatively, the runoff coefficient C in the rational method formula
can be calculated from the equation: C = 0.6Ia + 0.2
Where:
|
C = Watershed coefficient
|
|
Ia = Impervious area/total area
|
3. If the alternate form is to be submitted, the calculation of C shall
be provided as part of the drainage calculations.
(ii) Determination of Time of Concentration
1. The time of concentration is the amount of time required for surface
runoff to travel from the most hydraulically remote drainage point
to the drainage point under consideration. The most remote drainage
point refers to the route requiring the longest drainage travel time
and not necessarily the greatest linear distance. The flow routes
used in determining the time of concentration must take into consideration
future development as proposed by thoroughfare plans, zoning maps,
etc. Time of Concentration shall be calculated in accordance with
the procedure contained in the latest version of the TxDOT Hydraulics
Manual.
2. The following table contains minimum and maximum allowable times
of concentration. These times were derived from times of concentration
typically used in runoff determination calculations.
3. It should be noted when analyzing a storm drainage system that a
downstream inlet may have an inlet time exceeding the time of concentration
through the system to that point, therefore, the greatest time would
be used from the point downstream.
4. Times of concentration less than ten (10) minutes are not to be used,
except for, paved areas or roofs, unless the specific situation is
formally identified as unique and such is required by the City Engineer.
Areas
|
Minimum Time of Concentration
|
---|
Parks and Open Areas
|
20
|
Residential
|
10
|
Multifamily
|
10
|
Commercial
|
10
|
Industrial
|
10
|
Roofs and Paved Areas
|
5
|
(3) General
Requirements for Storm Design Analysis
(a) Curb and Gutter Streets.
Drainage systems for curb-and-gutter
pavements shall be underground closed conduits with the exception
to existing individual residential lot drainage. Installation shall
be calculated to where the stormwater runoff is of such a quantity
as specified in this section.
(b) Non-curb and Gutter Streets.
Drainage systems for pavement
without curb and gutter shall be roadside open-ditch sections. Open
channels or ditch methods may be used as specified in this article
to dispose of stormwater runoff of such a quantity that it exceeds
the height specified in this chapter. Such channels shall be in dedicated
easements to the City upon approval of the location and alignment
of such easements. All channels shall be designed and constructed
to terminate at an approved outlet.
(i) Alternative to Height Limitation.
If an underground
drainage system is required, and a sixty-inch (60") or smaller pipe
will handle the design flow, pipe shall be used. If a sixty-inch (60")
pipe is not adequate, concrete pipe or natural and/or open channels
and ditch methods is an option.
(4) Design
of Storm Sewers
(a) Design Frequency
(i) All Developments.
The following table shall provide
the storm frequencies to be used in storm drain designs for newly
developed areas, redevelopment or infill development.
Facility
|
|
|
---|
Street Capacity, Enclosed Pipe System (if needed), Side ditches
or Combination*
|
Residential, Commercial Industrial
|
Local - 5 years
Collector - 10 years
Arterial - 10 years
|
Culverts, Bridges, Channels and Creeks
|
Any Type of Area Less Than 1,000 Acres
|
25 years
|
Culverts, Bridges, Channels and Creeks
|
Any Type of Area More Than 1,000 Acres or Any Area Located in
a Special Flood Hazard Zone Designated Under the National Flood Insurance
Program
|
100 years
|
*Due to physical constraints, hydraulic gradient threatening
potential overflow which could cause damage or serious inconvenience
to surrounding properties, areas of historical drainage problems as
determined by the city engineer or representative, and/or future capital
improvement project intended to upgrade existing drainage, the flood
frequency may be increased to twenty-five (25) years.
|
(ii) Redevelopment or Infill Development:
Assuming no development
takes place. The storm drain will then be evaluated with the development
in place.
1. If the proposed redevelopment has a lower or equal impervious cover,
no modifications to the existing storm drain are required.
2. If the hydraulic gradient of the existing storm drain is below the
top of curb, no improvements to the existing storm drain are required.
3. If the hydraulic gradient is above the top of curb, and no structures
are threatened, the applicant must check with the City to see if a
Capital Improvement Project is proposed that will require a capital
contribution. If no Capital Improvement Project is in place for the
subject system and no structural flooding is threatened by the project
then no improvements to the existing storm drain are required.
4. If the hydraulic gradient indicates that structures are threatened
by flooding, the applicant has the option of either making improvements
to the existing storm drain or providing on-site detention.
(iii)
City Projects (Capital Improvement Programs).
Proposed City capital improvements may indicate a larger diameter
storm sewer is planned in the area proposed for drainage improvements.
The Department of Planning shall be consulted with on impact of new
development.
(iv) Private Drainage Systems.
Storm sewers for private drainage
systems shall conform to the City of Bellville Building Code.
(b) Velocity Considerations
(i) Minimum velocities should not be less than three (3) feet per second
with the pipe flowing full, under the design conditions.
(ii) Maximum velocities should not exceed eight (8) feet per second without
use of energy dissipation downstream.
(iii) Maximum velocities should not exceed twelve (12) feet per second.
(iv) In extreme conditions where the maximum velocity must be exceeded,
prior approval must be obtained from the City Engineer or representative.
(c) Pipe Sizes and Placement
Minimum Pipe Size
|
Minimum Box Size*
|
---|
15 inches inside or equivalent cross-section
|
2 feet x 2 feet
|
*Closed conduits (circular, elliptical, or box) shall be selected
based on hydraulic principal and economy of size and shape.
|
(i) Larger pipes upstream should not flow into smaller pipes downstream
unless construction constraints prohibit the use of a larger pipe
downstream, or the improvements are outfalling into an existing system,
or the upstream system is intended for use in detention.
(ii) Match crowns of pipe at any size change unless severe depth constraints
prohibit.
(iii) Locate storm sewers in public street right-of-way or in approved
easements. Back lot easements are discouraged.
(iv) Follow the alignment of the right-of-way or easement when designing
cast in place concrete storm sewers.
(v) A straight line shall be used for inlet leads and storm sewers.
(vi) Center culverts in side lot storm sewer easements.
(vii) Pipe soffits at changes in pipe sizes should be set at the same elevations.
(viii)
Vertical curves in the conduit will not be permitted, and horizontal
curves will be permitted only with the approval of the City Engineer
or representative. No reverse curves will be allowed.
(d) Starting Water Surface and Hydraulic Gradient
(i) The hydraulic gradient shall be calculated assuming the top of the
outfall pipe as the starting water surface.
(ii) At drops in pipe invert, should the upstream pipe be higher than
the hydraulic grade line, then the hydraulic grade line shall be recalculated
assuming the starting water surface to be at the top of pipe at that
point.
(iii) For the Design Storm, the hydraulic gradient shall at all times be
below the gutter line, at least one foot (1') below gutter line, for
all newly developed areas.
(e) Manhole Locations
(i) Use manholes at the following locations:
1. Size or cross-section changes.
2. Inlet lead and conduit intersections.
4. Required at bends greater than thirty degrees (30°) and pipe
junctions greater than forty-five degrees (45°).
6. A maximum spacing of six hundred feet (600') measured along the conduit
run.
(ii) Use manholes for existing monolithic-concrete storm sewers at the
same locations as above except for intersections of inlet leads unless
a manhole is needed to provide maintenance access at those intersections.
(iii) Do not place manholes in driveways or in the street in front of or
immediately adjacent to a driveway.
(iv) Where inlets serve as a manhole or junction box, the width of a new
standard inlet at a minimum, shall be equal to the outside diameter
of the largest pipe plus eight inches (8").
(f) Inlets
(i) Locate inlets at low points in the gutter.
(ii) Valley gutters across intersections are not permitted.
(iii) Inlet spacing is a function of gutter slope and should be designed
to conform with this section. The following shall be used:
1. Residential Development: Maximum spacing of inlets shall result from
a gutter run of seven hundred feet (700') from high point in pavement
to the adjacent inlet on a continuously graded street section, with
a maximum of fourteen hundred feet (1,400') of pavement draining towards
any one (1) inlet location.
2. Commercial Development: Maximum spacing of inlets shall result from
a gutter run of four hundred feet (400') from high point in pavement
to the adjacent inlet on a continuously graded street section with
a maximum of six hundred feet (600') of pavement draining toward any
one (1) inlet location.
3. Recessed inlets will be required on arterial and collector streets.
4. The minimum curb inlet size shall be five feet (5'). Maximum length
of inlet at any one curb location shall be twenty feet (20') on each
side of the street. Curb inlets are not allowed in intersection or
curb returns.
5. Do not use beehive grate inlets or other specialty inlets.
6. Do not use grate top inlets in unlined roadside ditch.
7. Do not place inlets in the circular portion of cul-de-sac streets
unless justification based on special conditions can be provided.
8. Place inlets at the end of proposed pavement, if drainage will enter
or leave pavement.
9. Do not locate inlets adjacent to esplanade openings.
10. Place inlets on side streets intersecting major streets, unless justification
based on special conditions can be provided.
11. For all new construction, convey public or private alleyway drainage
to an inlet prior to entering the public street drainage system.
(5) Overland
Flow
(a) Design Frequency:
Design frequency for consideration
of overland flow shall consider extreme storm events which exceed
the capacity of the underground storm sewer system resulting in ponding
and overland sheet flow through the development to the primary outlet.
(b) Relationship of Structures to Street:
All structures
shall be a minimum of one foot (1') higher than the highest level
of ponding anticipated resulting from the extreme event analysis.
(c) Calculation of Flow
(i) Streets shall be designed so that consecutive high points in the
street will provide for a gravity flow of drainage to the ultimate
outlet.
(ii) Cross flow along street intersections of arterial and collector streets
is prohibited unless otherwise determined by the City Engineer or
representative.
(iii) Maximum spread of water to be allowed in local streets at five (5)
year design flow shall allow for one (1) clear lane of traffic (twelve
feet (12') wide).
(iv) Maximum spread of water in collector streets at ten (10) year design
flow shall allow for one (1) clear lane of traffic each way (twelve
feet (12') wide).
(v) Maximum spread of water in arterial streets at ten (10) year design
flow shall allow for two (2) clear lanes of traffic (twenty-four feet
(24') wide).
(vi) Inverted crown sections are permitted only in alleys.
(vii) Street flow between lots can be provided only through a defined drainage
easement.
(viii)
A map shall be provided to delineate extreme event flow direction
through a proposed development and how this flow is discharged to
the primary drainage outlet.
(ix) In areas where ponding occurs and no sheet flow path exists, then
a calculation shall be provided showing that runoff from the 100-year
event can be conveyed and remain in compliance with the other requirements
of this paragraph.
(6) Design
of Open Channels
(a) Design Frequency
(i) Open channels shall be designed according to methods described in
the Fort Bend County Drainage Criteria Manual.
(ii) Design standards for channel construction shall follow the requirements
specified in the Fort Bend County Drainage Criteria Manual.
(iii) Design standards for outfalls into channels shall conform to those
in the Fort Bend County Drainage Criteria Manual.
(iv) A copy of the Fort Bend County Drainage Criteria Manual for open
channels is available online.
(7) Determination
of Water Surface Elevation
(a) Water
surface elevations shall be calculated using Manning’s Equation
and the Continuity equation.
(b) For
the design storm event, the water surface shall be calculated to remain
within banks.
(c) In
the absence of detailed calculation by Manning’s Formula for
the specific street section, the average velocities in the following
table may be used upon approval by the City Engineer or representative.
% Slope of Gutter
|
Assumed Velocity
(Ft./Sec.)
|
---|
2.0%
|
3.1
|
3.0%
|
3.8
|
4.0%
|
4.3
|
5.0%
|
4.9
|
6.0%
|
5.3
|
8.0%
|
6.1
|
10.0%
|
6.9
|
(8) Design
of Culverts
(a) Head loss in culverts shall conform to TxDOT Hydraulics Manual, Chapter
4, Culverts.
(b) Railroad
crossings shall be approved by the respected [respective] Railway
Company.
(9) Design
of Roadside Ditches
(a) Design Frequency
(i) Roadside ditch design is permissible only for single-family residential
lots or for commercial areas equal to or larger than one-half (0.5)
acres.
(ii) The design storm event for the roadside ditches or side ditches shall
conform to the table in this section.
(iii) Design capacity for a roadside ditch shall be to one-half foot (0.5')
below the edge of pavement or the natural ground at the right-of-way
line, whichever is lower.
(iv) The design must include an extreme event analysis to indicate that
structures will not be flooded.
(b) Velocity Considerations
(i) For grass-lined sections, the maximum design velocity shall be 3.0
feet per second during the design event.
(ii) A grass-lined or unimproved roadside ditch shall have side slopes
no steeper than three horizontal to one vertical (3:1), or as soil
conditions will permit.
(iii) Minimum grades for roadside ditches shall be -0.33 feet per one hundred
feet (100').
(iv) Calculation of velocity will use a Manning’s roughness coefficient
(n) of 0.045 for earthen section and 0.025 for ditches with paved
inverts.
(v) Use erosion control methods acceptable to the City when design velocities
are expected to be greater than three (3) feet per second.
(c) Culverts
(i) Culverts will be placed at all driveway and roadway crossings, and
other locations where appropriate.
(ii) Culverts will be designed assuming inlet control.
(iii) Roadside culverts are to be sized based on drainage area. However,
the minimum culvert sizes shall be fifteen inches (15") (residential)
and eighteen inches (18") (commercial). When requested, calculations
shall be provided for review.
(iv) Cross open channels with roadside culverts no smaller than eighteen
inches (18") inside diameter or equivalent. The size of culvert used
shall not create a head loss of more than 0.20 feet greater than the
normal water surface profile without the culvert.
(v) Stormwater discharging from a ditch into a storm sewer system must
be received by use of an appropriate structure.
(vi) Culverts shall be of approved class of reinforced concrete pipe (RCP)
or equivalent.
(vii) Safety standards for ends to driveway culverts adopted by TxDOT,
as amended, are hereby adopted by reference to the following extent.
1. Culverts of fifteen inches (15") in diameter or larger shall have
six (6) to one (1) safety end sections. The ground around the end
section shall have a grade of six (6) to one (1).
2. Culverts thirty-six inches (36") and larger in diameter may have
four (4) to one (1) safety end sections when approved by the City
Engineer or representative.
3. Pipe runners shall be required in accordance with TxDOT standards.
(d) Invert Protection
(i) Ditch invert protection shall be used when velocities exceed three
(3) feet per second.
(ii) Ditch invert protection will be used at the upstream and downstream
ends of all culverts.
(e) Depth and Size Limitations
(i) Maximum depth shall not exceed four feet (4') from adjacent edge
of pavement.
(ii) Ditches in adjoining and parallel easements shall have top of bank
not less than two feet (2') from the outside easement line.
(10) Design
of Outfalls.
Outfall design shall conform to Fort Bend
County Drainage Criteria Manual standards.
(11) Stormwater
Detention
(a) The intention of stormwater detention is to mitigate the effect of
the new development on an existing drainage system. Unless otherwise
determined by the City Engineer, the project engineer shall provide
calculations using acceptable design criteria to show that the impact
can be mitigated using detention criteria from the requirement list
in this section.
(b) Application of Detention
(i) The use of on-site detention is required when reported incidence
of structural flooding exists, or when infill or redevelopment will
result in a potential threat to existing structures unless the current
infrastructure is improved, or the City has developed a plan for a
detention facility to serve the overall area.
(ii) If the City of Bellville’s criteria or certain provisions within
the criteria are stricter than Austin County’s criteria, the
City of Bellville’s criteria shall prevail.
(iii)
If redevelopment occurs without increasing the overall impervious
character of the site, detention may not be required upon approval
by the City Engineer or representative.
(iv) If the proposed development has less or equal impervious land cover
than that used in the design of the storm sewer system as shown on
the drainage area map in the roadway construction plans or other hydraulic
computations, detention may not be required upon approval by the City
Engineer or representative.
(v) If the hydraulic grade line from the current design storm of the
receiving storm sewer system remains below the elevation of the gutter
throughout the system with the proposed development, detention may
not be required upon approval by the City Engineer or representative.
(c) Calculation of Detention Volume
(i) Detention volume for redevelopment areas is calculated on the basis
of the amount of area of increased impervious cover.
(ii) Areas Less Than Three (3) Acres:
Detention will be required
at the rate of 0.20 acre-feet per acre of increased impervious land
cover.
(iii)
Areas Greater Than Three (3) Acres But Less Than Ten (10) Acres:
Detention will be required at the rate of 0.45 acre-feet per
acre of increased impervious land cover.
(iv) For areas greater than ten (10) acres, the SCS Unit Hydrograph Method
and the Modified Puls Routing Method shall be used to determine the
size of the detention pond.
(v) Private parking areas, private streets, and private storm sewers
may be used for detention provided the maximum depth of flooding does
not exceed nine inches (9") directly over the inlet and paved parking
areas are clearly marked.
(vi) Private transport truck only parking may be used for detention provided
the maximum depth of flooding does not exceed fifteen inches (15")
directly above the inlet and, unless otherwise, signage is provided
stating that the area is subject to flooding during small rain events.
(d) Calculation of Outlet Size
(i) Detention pond discharge pipe into an existing storm sewer line or
existing City of Bellville ditch:
1. All detention facilities shall be analyzed for the five (5), ten
(10), twenty-five (25), and one hundred (100) year storm events. Analysis
for smaller events is required if the downstream channel has less
than a five (5) year capacity.
2. The maximum allowable release rate from a detention facility is equal
to the pre-development discharge rate for each storm event based on
existing conditions, unless there are specific conditions that warrant
approval of a variance by the City of Bellville.
(ii) Reducer or restrictor pipes shall be sized as follows:
1. Use the following equations to calculate the required outflow orifice:
Q = CA 2g h
|
D = Q1/2(2.25h1/4)
|
Where:
|
Q = Outflow discharge (cfs)
|
|
C = 0.8
|
|
A = Orifice area (square feet)
|
|
g = Gravitational factor (32.2)
|
|
h = Head, water surface differential (feet)
|
|
D = Orifice diameter (feet)
|
2. Restrictor shall be either of the required diameter or of the equivalent
cross-sectional area.
(e) Ownership and Easements
(i) Private Facilities
1. Pump discharges into a roadside ditch requires the submittal of pump
specifications on the design drawings.
2. The City reserves the right to prohibit the use of pump discharges
where their use may aggravate flooding in the public right-of-way.
3. Responsibility for maintenance of the detention facility must be
indicated by letter submitted to the City as part of the design review.
4. All private properties being served shall have drainage access to
the pond. Dedicated easements may be required.
5. No public properties drain into the detention area.
6. A private maintenance agreement is provided when multiple tracts
are being served.
(ii) Public Facilities
1. Facilities will only be accepted for maintenance by the City in cases
where public drainage is being provided.
2. The City requires a maintenance work area of twenty-foot (20') width
surrounding the extent of the detention area. Public rights-of-way
or permanent access easements may be included as a portion of this
twenty-foot (20') width surrounding the extent of the detention area.
Public rights- of-way or permanent access easement may be included
as a portion of this twenty-foot (20') width.
3. A dedication of easement shall be provided by plat or by separate
instrument.
4. Proper dedication of public access to the detention pond must be
shown on the plat or by separate instrument. This includes permanent
access easements with overlapping public utility easements.
(12) Drainage
System Criteria.
If an underground drainage system is
required, and a sixty-inch (60") or smaller pipe will handle the design
flow, pipe shall be used. If a sixty-inch (60") pipe is not adequate,
concrete pipe or natural and/or a lined open drainage channel is an
option. If pipe is selected, the maximum allowable velocity shall
be twelve (12) fps in the pipe. Lining materials, if used, shall be
approved by the City.
(13) Habitable
Structures.
Adequate means for stormwater runoff in excess
of the street’s “design storm” capacity (i.e., five-,
ten-year (5, 10 yr.) storm) shall be provided to flow around habitable
structures. Whichever one of the following methods provides the greatest
finished floor foundation shall be used:
(a) If adjacent topography rises away from the street, a grading/drainage
plan shall be provided which shows that all building sites can provide
a finished floor elevation:
(i) At least one foot (1') above the top of the curb using the highest
point along the portion of such curb fronting the building site; or
(ii) At least one foot (1') above the top of ditch elevation using the
highest point along the portion of such ditch fronting the building
site.
(b) If adjacent topography falls away from the street, a grading/drainage
plan shall be provided which shows that all building sites can provide
a finished floor elevation at least one foot (1') above the ground
elevation along all sides of the building site.
(c) The building foundation guidelines for surface drainage set forth
in the International Building Code, as amended.
(d) All streets shall be designed and constructed to minimize any fill
required to bring building pads into compliance with this document.
(e) Alternate methods of building protection of those above may be accepted
by the City upon submittal of detailed, engineered plans.
(E) Easements
and Right-of-Way
(1) Easements.
In addition to any other provisions of this Code relating to
easements of public improvements. The following requirements for easements
for public drainage improvements, channels and facilities required
for any development by this section shall apply.
(a) General Provisions
(i) All public drainage systems and facilities, which are not to be included
within an existing or proposed public street right-of-way, shall be
located within an existing or proposed public street right-of-way
[sic], shall be located within easements to be dedicated to the City,
and shall have adequate access to a public street. Prior to acceptance
of any public drainage facilities, all easements within which the
facilities are located shall be cleared of all buildings, structures,
fences or other obstacles that would interfere with access to the
easements. Restrictions of easements shall be described on the final
plat or plan using City guidelines.
(ii) Drainage easements through residential lots shall be placed entirely
on one (1) lot. No split lot easements are allowed unless otherwise
approved by the City Engineer or representative.
(iii) No structures, eaves and overhangs, fences, storage sheds, decks,
pools, landscaping or other above-ground man-made improvements shall
be permitted in drainage easements. This provision includes, but is
not limited to, areas encompassing floodplain, channels, flumes, natural
creeks or swales, and any other condition that relies on a drainage
easement to convey stormwater through surface flow.
(iv) Major creeks, streams or other natural drainageways shall generally
remain in an open natural condition free of artificial impoundments.
Minor creeks or branches may be channelized provided such improvements
are designed and constructed in conformity with the city’s approved
plans and specifications.
(v) Where artificial channels are to be provided, an easement of sufficient
area to encompass a channel designed in accordance with the city’s
approved standards and specifications must be dedicated in favor of
the public. Such easement must include a sufficient area for access
and maintenance running parallel and adjacent to each side of the
channel.
(vi) When a new subdivision is traversed by or adjacent to any creek,
stream or other natural drainageway, stormwater drainage easements
following the general course of the stream shall be dedicated in favor
of the public. At a minimum, such easement shall include the area
between the high banks of the channel together with the parallel and
adjacent areas extending twenty feet (20') on either side of the channel.
(vii) Lateral easements of at least fifteen feet (15') in width must provide
access to all drainage easements from adjacent streets for maintenance
purposes. Such easements must be provided at intervals of not greater
than fifteen hundred feet (1,500').
(viii)
Where a proposed artificial drainage system will carry water
across private lands outside of the subdivision, appropriate drainage
easements must be secured by the persons responsible for the new development.
(b) Above-Ground Systems.
Where an access road is required
adjacent to a channel, an additional easement area of a minimum width
of fifteen feet (15') shall be provided. The maximum cross slope shall
be five percent (5%).
(c) Closed Systems
(i) Storm sewers within easements shall be placed no closer than seven
and one-half feet (7.5') measured from the outside edge of the pipe
to the edge of an easement, except when adjoining another easement
or public right-of-way. The total width of an easement shall be equal
to the maximum depth of the line plus twice the outside diameter of
the storm sewer. The storm sewer shall be placed in the center of
the easement. When the storm sewer adjoins a public right-of-way,
the easement may be reduced and the storm sewer may be aligned closer
to the right-of-way line with specific approval of the City. In all
cases, the minimum width of a storm sewer easement shall be fifteen
feet (15') with the sewer located in the center of the easement.
(ii) Utilities such as water and sanitary sewer lines may share a portion
of a drainage easement, containing an underground enclosed drainage
system where an additional easement width for a minimum of ten (10)
feet may be required to create a public drainage and utility easement.
No utilities shall be located in any lined channel, pipe, or box in
such a way as to interfere with flow capacity or maintenance of or
access to the channel, pipe or box.
(iii) A drainage easement shall be provided for the area within a required
outfall channel or ditch to the point where the flow line “day
lights” on natural grade, or matches existing topography.
(iv) To provide for maintenance, a drainage easement shall be provided
at least fifteen feet (15') beyond any outfall headwall.
(F) Responsibility
for Maintenance of Detention Facilities
(1) Detention
facilities shall remain the responsibility of property owners within
the subdivision.
(2) Covenants,
filed of record and running with the land shall make provision for
a maintenance entity authorized to assess the costs of detention facility
repair and maintenance to lot owners within the subdivision. Such
covenants shall provide for a lien against the subdivision lots to
secure payment of the assessed costs. In addition, such covenants
shall authorize, but not obligate, the city to exercise such maintenance
and assessment power in place of the maintenance entity and to secure
the assessed costs with a lien against the subdivision lots.
(G) Submittals
(1) Preliminary
Submittals -
Submittal, for review and comment, of one
(1) line drawing is recommend and may be required as part of the platting
process. One (1) line drawing should include:
(a) Approximate
definition of lots and street patterns.
(b) The
approximate drainage areas for each system.
(c) A
definition of the proposed drainage system by single line.
(d) Any
proposed drainage easements.
(e) The
proposed pipe diameters.
(f) Floodplain
information, including floodplain boundary, in [if] any; FEMA map
number, effective map date and zone.
(2) Final
Design -
Submit the following for approval:
(a) Copies
of any documents which show approval of exceptions to the City design
criteria.
(b) Design
calculations for storm line sizes and grades, and for detention facilities,
if any.
(c) Design
calculations for the hydraulic grade line of each line or ditch, and
for detention facilities, if any.
(d) Contour
map and drainage area map of the project.
(e) Plan
and profile sheets showing stormwater design (public facilities only).
(f) Projects
located within a floodplain boundary or within a floodplain management
area shall:
(i) Show the floodplain boundary or floodplain area, as appropriate,
on the one (1) line drawing or drainage area map.
(ii) Comply with all applicable submittal requirements contained herein.
(3) Signature
Stage -
Submit the following for approval:
(c) Stormwater
detention maintenance agreement letters.
(d) Include
drainage area map and supporting calculations of drawings.
(H) Qualms
Assurance.
Prepare calculations and design drawings under
the supervision of a Texas Professional Engineer trained and licensed
under the discipline required by the project scope. The final design
drawings and all design calculations must be sealed, signed, and dated
by the Professional Engineer responsible for the development of the
drawings.
(I) Design
Analysis
(1) Projects
shall be tied to National Geodetic Survey (NGS) datum adjustment which
matches the Federal Emergency Management Agency (FEMA) rate maps or
the most current NGS datum which matches the FEMA rate maps. In the
event GPS surveying is used to establish benchmarks, at least two
(2) references to benchmarks relating to the FEMA rate maps shall
be identified. Equations may be used to translate other datum adjustments
to the required adjustment.
(2) Drawing
sets shall include a drainage area map, which will contain calculations
of flow by the rational method.
(Ordinance 1419, exhibit 9A, adopted 8/24/10)
All natural gas system work shall be in strict compliance with
D.O.T. Title 49, Part 192, Transportation of Natural and Other Gas
by Pipeline: Minimum Federal Safety Standards and the Texas Railroad
Commission Gas Utilities Division minimum pipeline safety standards.
All persons performing work on the natural gas system shall be appropriately
qualified under these regulations.
The following minimum standards apply to natural gas system
extensions within the City of Bellville.
(A) Mains
(1) Minimum
Diameter -
Two inches (2").
(2) Depth
-
Three feet (3') of cover below final grade.
(3) Material
-
Type: Polyethylene conforming to the requirements of
the ASTM D-2513 (current edition) specification “Thermoplastic
Gas Pressure Pipe, Tubing and Fittings.” Standard Dimension
Ratio: SDR-11, minimum.
(4) Pressure
Test -
Mains (and services, if connected): Ninety (90)
pounds per square inch for one (1) hour minimum. The pressure test
shall be conducted with a gauge with a recording chart. A record of
the successful test must be delivered to the City for its files.
(5) Trace
Wire -
Twelve (12) gauge thermoplastic insulated solid,
direct burial conductive copper wire securely bonded together at all
joints and pipe intersections and accessible at all valve boxes and
services. Wire connectors to be 3M DBR or approved equal and shall
be watertight and provide electrical continuity.
(6) Heat
Fusion Joints -
All persons making heat fusion joints
must be currently certified to make such joint. A copy of the certificate(s)
must be furnished to the City.
(B) Valves
(1) Locations
-
Must conform to the City’s Sectionalizing Valve
Plan.
(2) Material
-
Polyethylene valve stub ends must be compatible with
the pipe specified above including the Standard Dimension Ratios (SDR).
(3) Type
-
Rockwell Polyvalve Ball Valves.
(C) Fittings
(1) Material
-
Polyethylene conforming to the requirements of ASTM
D-2683 specification “Socket-Type Polyethylene Fittings for
Outside Diameter Controlled Polyethylene Pipe” or ASTM D-3261, “Butt
Heat Fusion Polyethylene (PE) Plastic Fittings for Polyethylene (PE)
Plastic Pipe and Tubing.”
(2) Standard
Dimension Ratio -
Eleven (11).
(D) Service
(1) Tapping
Tee -
Polyethylene with one inch (1") cutter.
(2) Fitting
and Pipe Material -
Polyethylene conforming to specifications
for mains above.
(3) Size
-
One inch (1") diameter.
(4) Pressure
Test -
Unless tested with mains, services must be tested
to ninety (90) pounds per square inch gauge for ten (10) minutes.
(5) Trace
Wire -
Twelve (12) gauge thermoplastic insulated solid,
direct burial conductive copper wire securely bonded to trace wire
on main. Wire connectors to be 3M DBR or approved equal and shall
be watertight and provide electrical continuity.
(6) Marking
-
“Record Drawing” plans required to show
location of services. End of services not connected to an existing
structure shall be marked with four-foot (4') long (two-foot (2')
buried) two-inch (2") diameter Schedule 40 PVC painted yellow.
(E) Backfill
(1) Under
Asphalt Streets -
One and one-half (1.5) sack per cubic
yard cement stabilized sand.
(2) Other
Locations -
Sandy soil must be water jetted; other soil
may be compacted with mechanical compactors.
(F) Tests
(1) All
testing shall be in accordance with D.O.T. Title 49, Part 192, Transportation
of Natural and Other Gas by Pipeline: Minimum Federal Safety Standards.
(2) If services
are installed at the same time as the main, the services and main
may be tested at the same time. If the services are installed after
the main is in service, each service shall be tested. Each service
shall be pressurized to ninety (90) psig for twenty (20) minutes.
During that period, the service shall be leak-free. If leaks are found,
appropriate repairs shall be made.
(Ordinance 1419, exhibit 9A, adopted 8/24/10)