Provisions shall be made in the subdivision, when appropriate, for the extension of major streets in accordance with the Master Plan of the City of Midlothian. Collector streets shall be provided through residential and nonresidential subdivisions bounded by arterial streets whereby adequate circulation of traffic flow is provided between the arterial streets and the subdivisions. Adequate local streets shall be provided to accommodate traffic flow within the subdivision.
1. 
Where such is not shown in the Master Plan, the arrangement of streets in a subdivision shall either:
a. 
Provide for the continuation or appropriate projection of existing principal streets in surrounding areas, or
b. 
Conform to a plan for a neighborhood, approved or adopted by the City to meet a particular situation where topographical or other conditions make continuance or conformance to existing streets impractical.
2. 
Boundary Streets:
In cases where the land proposed to be subdivided is partially or totally bounded on one or more sides by an existing street, way, or artery having width less than that specified in this Ordinance, the subdivision shall be laid out so as to provide the street right-of-way width required.
A half-street along adjoining property which has not been subdivided may be approved; however, if it is deemed necessary by the City that the full width of the street be obtained, then the developer of the first tract to be subdivided may be required to obtain the additional or remaining right-of-way from the adjacent tract, or dedicate sufficient right-of-way for the street paving and installation of utilities. Boundary streets shall be improved as a part of the subdivision development.
3. 
Street Intersections:
More than two (2) streets intersecting at a point shall be avoided.
Where several streets converge at one point, or acute intersection angles are present, setback lines, special rounding or cutoff corners may be required to insure safety and facilitation of orderly traffic movements.
For maximum traffic safety and ease of traffic operations, all street intersections should intersect at ninety (90) degree angles.
No arterial street shall intersect any other arterial street at an angle that varies from a ninety (90) degree angle of intersection by more than five (5) degrees.
An intersection of two collector streets shall not vary from a ninety (90) degree angle of intersection by more than ten (10) degrees.
An intersection of local streets shall not vary from a ninety (90) degree angle of intersection by more than fifteen (15) degrees.
Street intersections with arterial or collector streets shall have property line corner radii with a minimum tangent distance of twenty-five (25) feet or a distance as determined by the City.
4. 
Dead-End Streets, Cul-de-Sacs and Courts:
Dead-end streets shall not be approved unless:
a. 
Such streets are designed to connect with future streets in adjacent land not yet subdivided, in which case the streets shall extend to the boundaries of the land being subdivided and a temporary turnaround must be provided. Lots may not front on dead-end expansion streets.
b. 
Cul-de-Sacs, courts or places may be permitted where the form or contour of the land or the shape of the property makes such street design appropriate. Such cul-de-sacs, courts or places shall provide proper access to all lots and shall generally not exceed six hundred (600) feet in length from the centerline of the intersection to the radius point and no more than 25 lots may be served by a cul-de-sac. A turnaround shall be provided at the closed end which has a minimum right-of-way radius of sixty (60) feet, and an outside roadway (pavement) radii of at least forty and one-half feet (40.5'), except that if an equally safe and convenient form of paved space is approved by the Commission in place of a turning circle, such approved space may be improved as agreed upon. Cul-de-sacs in industrial or commercial developments shall not exceed a distance length of 600 feet and will have a right-of-way radius of 75 feet, and an outside roadway (pavement) radii of sixty-five and one-half feet (65.5'), or other provisions as approved by the City.
c. 
The cul-de-sacs or courts are part of a Community Unit or Planned Development approved by the City where such arrangements are part of the overall neighborhood design.
5. 
Relation of Adjoining Streets and Land:
The system of streets designated for the subdivision, except in unusual cases, must connect with streets already dedicated in adjacent subdivisions, and where adjacent connections are not platted, must, in general, be the reasonable projection of streets in the nearest subdivided tracts, and must continue to the boundaries of the tract subdivided, so that other subdividers may connect therewith. Reserve strips of land controlling access to or egress from other property, or to or from any street or alley, or having the effect of restricting or damaging the adjoining property for subdivision purposes or which will not be taxable or accessible for special improvements shall not be permitted in any subdivision.
6. 
Local streets shall be so laid out that their use by through traffic will be discouraged. Street jogs with centerline offsets of less than one hundred and thirty-five (135) feet shall be prohibited unless otherwise approved by the City Engineer.
7. 
Where a residential subdivision abuts or contains an existing or proposed railroad or highway, the City may require the developer to provide marginal access streets, reverse frontage with screen planting contained in a non-access reservation along the rear property line, deep lots with rear service alleys, landscaped berms, a noise barrier fencing that is a solid masonry fence at least six (6) feet in height, or such other treatment as may be deemed necessary by the Planning and Zoning Commission for adequate protection of residential properties and to afford separation of through and local traffic. Local street connections to arterial streets, highways or the crossing of railroads shall be as few as practical and located opposite existing streets.
8. 
Curve Requirements (Other than Intersections):
Arterial streets shall have a minimum radii at the centerline of one thousand (1000) feet; collector streets shall have a minimum radii at the centerline of five hundred (500) feet; and local streets and alleys shall have a minimum radii at the centerline of one hundred and fifty (150) feet.
9. 
Blocks:
The lengths, widths and shapes of blocks shall be determined regarding:
a. 
Provision of adequate building sites suitable to the special needs of the type of use proposed.
b. 
Zoning requirements as to lot sizes and dimensions.
c. 
Needs for convenient access, circulation, control and safety of traffic.
d. 
Limitations of topography.
Where no existing subdivision controls, the blocks shall not exceed one thousand three hundred twenty (1320) feet in length nor be less than six hundred (600) feet in length, except in certain instances where topographical features warrant special consideration. These limits shall be exceeded only upon specific approval by the Planning and Zoning Commission. Blocks longer than six hundred (600) feet shall be avoided in business districts or as approved by the Planning and Zoning Commission.
10. 
Street Width and Paving Width
Table 6-1
Type
Design Speed MPH
Street Right-of-Way Width
(ft.)
No. Of Lanes & Width
(ft.)
Paving Width (Back to Back of Curb)
(ft.)
Major Arterial
45
120
6
2 - 37
Minor Arterial
45
90
4
2 - 25
Major Collector
40
80
4
49
Minor Collector
35
60 or 70
3 or 4
37 or 45
Local Street
35
50
2
31
Local Street with ≥ 1 acre lots
35
60
2
28 (No Curb)
Figure 6-1. Design Controls for Vertical Curves
11. 
Street Grades:
Arterial streets may have a maximum grade of six (6) percent for a maximum continuous distance of two hundred (200) feet. Collector and local streets may have a maximum grade of eight (8) and ten (10) percent, respectively. Streets located within areas that have general subsurface conditions meeting either the Group 1 or Group 2 soil classification, as detailed in Section 6.16-2, must have a minimum grade of at least three-quarters (3/4) of one (1) percent. All streets located in areas meeting the Group 3 soil classification. [sic] Centerline grade changes with an algebraic difference of more than one (1) percent shall be connected with vertical curves to provide a minimum of four hundred (400) feet of stopping sight distance on arterial streets; three hundred (300) feet of stopping sight distance on collector streets and one hundred twenty-five (125) feet on local streets. All vertical curve lengths shall be established from Figure 6-1 for the various design speeds with respect to algebraic differences in grade. Whenever a cross-slope is necessary or desirable from one curb to the opposite curb, such cross-slopes shall not be less than one-eighth (1/8) inch in one (1) foot or more than one-half (1/2) inch in one (1) foot. Variance from these criteria may be allowed upon findings of fact by the developer and upon approval by the City Engineer.
12. 
Street Signs:
Street name signs shall conform to Section 5.12.
13. 
Fire Hydrant Locators:
Fire hydrant locators shall consist of four-inch by four-inch (4" x 4") blue reflector traffic buttons, installed at the third point of paving and shall be installed opposite each fire hydrant on all streets.
14. 
Minimum Radius:
Unless otherwise approved by the City Engineer, the required radius for curb returns at intersections shall be as follows:
Intersection Classification
Min. Radius
(ft.)
Arterial/Arterial
75
Arterial/Collector
75
Collector/Collector
50
Arterial/Local
35
Collector/Local
30
Local/Local
20
(Ordinance 88-14, sec. 6.11, adopted 7/26/88; Ordinance 98-11, sec. 1(D), adopted 2/10/98; Ordinance 2001-39, sec. 1(2), adopted 8/28/01; Ordinance 2002-14, sec. 1(1), adopted 3/26/02; Ordinance 2004-17 adopted 4/6/04; Ordinance 2021-36 adopted 5/11/21)
No alleys shall be permitted unless first approved by the City Council following receipt of a recommendation from the Planning and Zoning Commission. If authorized, alleys shall be designed and constructed in accordance with the following minimum specifications:
1. 
The minimum width of an alley right-of-way shall be 20 feet in industrial and commercial areas and 15 feet in residential areas. Alley turn-outs shall be paved to the property line, with a pavement width of at least 12 feet. Paving radius shall be a minimum of fifteen (15) feet at intersections with all streets.
2. 
Alley intersections and sudden changes in alignment shall be avoided, but, where necessary, lot corners shall be cut off at least 15 feet on each tangent to permit safe vehicular movement.
3. 
Dead-end alleys shall be avoided where possible, but if unavoidable, shall be provided with adequate turn-around facilities, as determined by the City.
4. 
All alleys shall be paved, and the paving shall be reinforced concrete conforming to Section 6.16 of this Ordinance. Alley paving shall be a minimum of twelve feet (12') wide in residential areas and sixteen feet (16') wide in commercial and industrial areas.
(Ordinance 88-14, sec. 6.12, adopted 7/26/88; Ordinance 98-11, sec. 1(D), adopted 2/10/98; Ordinance 2002-14, sec. 1(2), adopted 3/26/02; Ordinance 2016-43, sec. 1(C), adopted 11/8/16)
1. 
Easements across lots on rear or side lot lines shall be provided for utilities when necessary and shall be at least 15 feet wide, and as determined by City Engineer.
2. 
Where a subdivision is bounded by or contains a watercourse, drainageway, channel, or stream, there shall be provided a stormwater easement or drainage easement conforming substantially to the lines of such watercourse, or of such width to provide for any future anticipated construction, plus 10 feet on each side.
(Ordinance 88-14, sec. 6.13, adopted 7/26/88; Ordinance 98-11, sec. 1(D), adopted 2/10/98)
1. 
All lots shall conform to the regulations as set forth in the City’s Zoning Ordinance with the exception of lots located in the Extraterritorial Jurisdiction.
2. 
Corner lots in residential areas shall be wider than inside lots so as to allow an appropriate setback from both streets.
3. 
Access to lots shall be subject to the following:
(a) 
Each lot shall front onto a public street.
(b) 
Lots with street frontage at both front and rear shall be avoided when possible.
(c) 
No driveway access shall be allowed to a Freeway, Highway, Farm to Market Road, frontage or back roads serving a Highway, Major or Minor Arterial Street, and/or a Major Collector street from a residentially zoned lot or a lot developed or proposed to be developed for residential uses without the prior approval of the Planning Director and City Engineer.
(d) 
If the Planning Director and/or City Engineer deny a request to authorize driveway access to a Freeway, Highway, Farm to Market Road, frontage or back roads serving a Highway, Major or Minor Arterial Street, and/or a Major Collector street from a residentially zoned lot or a lot developed or proposed to be developed for residential uses, the requesting party may appeal such request to the Planning and Zoning Commission by submitting a written request for such appeal to the Planning Director not later than ten (10) days after receipt of written notification of the denial of the request. If an appeal is timely filed, the request shall be placed on the agenda of the Planning and Zoning Commission for review and consideration at its first regular meeting occurring after the fifteenth day after receipt of the appeal. The Planning and Zoning Commission may only grant or deny the request based on the request as presented to and denied by the Planning Director and/or the City Engineer. The decision of the Planning and Zoning Commission on an appeal made pursuant to this Paragraph (d) shall be final.
(e) 
Based on the determination of the Planning Director and City Engineer or their designated representative, new driveways shall be aligned with pre-existing driveways on the opposite side of the street and/or existing or future planned median openings where feasible.
4. 
Side lines of lots shall be approximately at right angles to straight street lines and radial to curved street lines.
5. 
For subdivisions where sanitary sewer disposal is authorized to be provided by means of an on-site sewage facility pursuant to Section 13.03 [Article 13.03] of the Code of Ordinances, as amended, such facility shall be designed, installed and maintained in accordance with all applicable laws, orders, ordinances and regulations.
6. 
A lot or parcel served by an on-site sewage facility of any type must have an area of not less than one (1) acre located outside of a designated floodplain; provided, however, if applicable state or county laws, orders, or regulations regulating on-site sewage facilities require a minimum lot or parcel area larger than one (1) acre, in which case such other laws, orders, or regulations shall control.
7. 
Subdivisions containing forty (40) or more lots shall be designed to have more than one street for entry and exit and with driveway access to interior streets only. Smaller subdivisions or individual lots with direct driveway access to arterial streets must provide a minimum driveway spacing of 150 feet, and a minimum street spacing of 1,000 feet. All lots fronting on major collectors or minor arterials shall be designed with sufficient turnaround room to prevent backing into high volume roads.
8. 
[Reserved]
9. 
A lot grading plan shall be submitted as a part of the construction plans. The plan shall be consistent with the drainage area map and include proposed contours, spot elevations and flow arrows to clearly indicate where and how the flow from each lot will be conveyed or intercepted. Type A, B or C drainage for each lot as described in HUD (FHA) Data Sheet 72, as amended, shall be identified on the plan. Type 1 or 2 block grading shall be provided unless special provisions are made for all Type 3 and 4 block grading and approved by the City Engineer.
(Ordinance 88-14, sec. 6.14, adopted 7/26/88; Ordinance 98-11, sec. 1(D), adopted 2/10/98; Ordinance 2002-14, sec. 1(3), adopted 3/26/02; Ordinance 2004-17 adopted 4/6/04; Ordinance 2016-43, sec. 1(D), adopted 11/8/16; Ordinance 2017-62 adopted 8/22/17; Ordinance 2022-34 adopted 6/28/22)
1. 
Accuracy:
All survey work around the boundary area as well as within the subdivision shall have an error of closure of one foot in fifteen thousand feet (1/15,000) or less.
2. 
The surveyor responsible for the Plat, shall place permanent monuments at each corner of the boundary survey of the subdivision. These monuments shall be a concrete post, four (4) inches in diameter and four (4) feet long, or other such type of monuments as shall be approved by the City. The precise point of intersection is to be indented on the top of the monument. Block corners shall be referenced to these monuments and the bearing and distances of the reference lines filed in written form with the City. Tops of monuments shall be set flush with existing ground level in non-paved areas. Elevations and locations of monuments shall be shown on the Final Plat.
(Ordinance 88-14, sec. 6.15, adopted 7/26/88; Ordinance 98-11, sec. 1(D), adopted 2/10/98)
1. 
Standard Specifications and Construction Details:
All improvements shall be in accordance with these regulations and the City of Midlothian Standard Construction Details, Sheets [sic] and as may be amended from time to time, and are added to this ordinance a [as] Appendix E [sic] and are made a part hereof for all purposes as if fully copied herein, unless and until City Council adopts a resolution or ordinance to adopt these Standard Specifications and Construction Details as a separate regulatory document.
Improvements not covered in the Standard Construction Details shall be in accordance with the Standard Specifications, as issued by the North Central Texas Council of Governments (latest revision) 1997, hereinafter referred to as COG specifications, and adopted and modified by the City of Midlothian, Texas.
2. 
Subgrade Stabilization:
In the Midlothian area there are two geological formations, the Eagle Ford and the Austin Chalk. The general subsurface soils conditions can be divided into the following groups:
Group 1: Highly plastic, expansive residual clay and shay clays of the Eagle Ford Geological Formation, having plasticity indices ranging from approximately 40 to 48, and a raw California Bearing Ratio (CBR) value ranging from 1 to 4. This group is generally located west of the ridge line running through town.
Group 2: Highly plastic expansive residual clays of the Austin Chalk Geological Formation, having plasticity indices ranging from approximately 33 to 45 and a raw CBR value ranging from 2 to 5. This group is generally located east of the ridge line running through town.
Group 3: Low to moderately plastic limey clays and severely weathered limestones of the Austin Chalk Geological Formation, having plasticity indices ranging from approximately 10 to 22 and a raw CBR value ranging from 6 to 10. This group is generally located along the ridge line.
If requested, the developer shall furnish the results of soils tests performed by an approved independent soils laboratory and a pavement analysis design performed by the developer’s engineer under specific loading conditions.
Soil samples to determine the Plasticity Index (PI) of the soil at the ultimate level of the pavement base course, shall be taken at least once per block or every 500', whichever is less, with a minimum of two (2) samples per project.
Should the PI vary considerably from one sample to another, additional samples will be taken as determined by the City.
Soil stabilization under concrete pavements will not be required if the PI of the soil is 15 or less, or as approved by the City Engineer.
If the P1 exceeds 15, soil stabilization to a depth of at least eight (8) inches will be required utilizing eight (8) percent by weight of lime.
If the PI exceeds 20, soil stabilization to a depth of at least eight (8) inches will be required utilizing either eight (8) percent by weight of Portland Cement or eight (8) percent by weight of lime.
3. 
Paving
a. 
Concrete Strength Requirements:
1. 
Concrete Curb and Gutter:
Concrete curb and gutter shall be constructed of a concrete batch design, having not less than 3600 psi compressive strength in 28 days, and shall be reinforced with #4 steel rebars.
2. 
Reinforced Concrete Pavement and Monolithic Curb:
Concrete pavement and monolithic Curb properly and continuously reinforced shall be constructed of a concrete batch design providing no less than 3600 psi compressive strength in 28 days.
b. 
Pavement Thickness Requirements:
All streets shall be designed and constructed with adequate thickness. Pavement shall be reinforced concrete having not less than 3600 psi compressive strength in 28 days. Reinforcing shall consist of #4 steel rebars on twenty-four (24) inch centers both ways and in accordance with the City of Midlothian Standard Construction Details. Concrete compressive strength tests shall be performed by an accredited testing lab as approved by the City Engineer. Table 6-2 indicates the pavement thickness requirements for each street classification and each soil group.
Table 6-2. Design Pavement Thickness
Street Classification
Pavement Thickness
Local Street with ≥ 1 acre lots
6"
Local Street
6"
Minor Collector
7"
Major Collector
8"
Minor Arterial
8"
Major Arterial
8"
The above pavement thickness and subbase stabilization will be acceptable without performing design calculations. Any proposed pavement section of lesser thickness or alternate materials or subbase stabilization shall be fully documented by the design engineer and must be approved by the City Engineer.
c. 
Concrete Curb And Gutter:
All pavement sections shall include concrete integral or attached curbs, with strength requirements listed in Section 6.16.3.a, and constructed in accordance with standard City of Midlothian construction specifications.
d. 
Bar Ditches
1. 
Curbs are not required on single-family residential lots one (1) acre or greater in size. However, if any lots within the overall subdivision are less than one (1) acre in size, then curb and gutter shall be required throughout the entire subdivision.
2. 
When curbs are not constructed within the single-family residential subdivision, in accordance with Section 6.16.3.d.1, the following shall apply:
a) 
Bar ditches shall be placed within the parkway area with a maximum slope of 4:1 and maximum depth of twenty-four inches (24"), unless otherwise directed by the City Engineer.
b) 
After ditches are shaped, they shall be immediately hydromulched and maintained through the life of the one-year maintenance bond period.
c) 
All driveways shall include reinforced concrete culvert pipe, type III, with concrete headwalls and sloped-end treatment. All sizing and construction shall be in accordance with City of Midlothian Standard Construction Details, and as directed by the City Engineer.
e. 
Paving Standards for Residential Parking, Loading, Drives, Vehicles, Sidewalks and Storage Areas Outside of the Right-of-Way
1. 
Except as provided in Subparagraph 2 of this Paragraph e, all required off-street parking, loading, drives, vehicle, sidewalk and/or storage areas outside of the right-of-way shall be paved with four (4) inches of concrete, minimum 3000 psi with #3 rebar laid 18 inches on center each way or #4 rebar laid 24 inches on center each way. No wire mesh shall be permitted in constructing the concrete areas described in the Paragraph e.
2. 
If the distance from the public right-of-way to the main dwelling unit located on the Property is greater than one hundred feet (100'); the City Engineer may approve an alternative driveway and parking area surface in lieu of concrete subject to compliance with all of the following conditions:
a. 
A concrete approach complying with the requirements of subparagraph 1 of this paragraph is constructed from the street toward the main dwelling unit for a distance of not less than the longer of (i) 25 feet commencing at the edge of the existing paved street adjacent to the property and (ii) the distance from the edge of the existing paved street adjacent to the property to the boundary of the existing street right-of-way;
b. 
A concrete parking area not less than 25 feet wide and extending not less than 20 feet from the exterior wall of the main dwelling structure where the garage doors are located shall be constructed adjacent to the garage entryway(s);
c. 
The plans and specifications for the alternative drive surface must be designed and sealed by a professional engineer and certified to be an all-weather surface that will support vehicles with a gross weight of up to 90,000 pounds and shall be subject to final review and approval of the City Engineer prior to issuance of a building permit for the dwelling unit to be constructed on the property; and
d. 
No certificate of occupancy or approval of a final inspection for the dwelling unit constructed on the property shall be granted until the City Engineering and Building Department has inspected the alternative drive surface and determined that such surface has been constructed in accordance with the approved plans and specifications.
3. 
Driveway approaches for all lots to be developed with single-family residential structures shall be not less than twelve feet (12') wide with a radius of not less than ten feet (10').
4. 
Sidewalks
a. 
Concrete sidewalks having a width of not less than four (4) feet and thickness of not less than four (4) inches shall be constructed of 3,000 psi concrete with #3 steel rebars on eighteen (18) inch centers, both ways and in accordance with standard City of Midlothian construction specifications. Sidewalks shall be located on both sides of all streets and thoroughfares within a single-family, multifamily, commercial or industrial subdivision. Sidewalks shall be constructed one (1) foot from the property lines within the street right-of-way and shall extend along the street frontage including the side of corner lots and block ends. Construction of sidewalks adjacent to curbs in residential areas will be considered only where driveway entrances are constructed from the rear of lots on each side of the street for the full length of the block. In these instances, the sidewalk shall be 5 feet wide.
b. 
Sidewalks shall be constructed in a manner that meets the American Disability Act (ADA) requirements for handicap accessibility at street intersections and adjoining individual driveways. Sidewalks shall be constructed without any encroachments of utility poles, trees, mailboxes, etc.
c. 
Sidewalks are not required on single-family residential lots one (1) acre or greater in size. If any lots within the overall subdivision are less than one (1) acre in size, then sidewalks shall be constructed throughout the entire subdivision.
d. 
Concrete compressive strength tests shall be performed by an accredited testing lab as approved by the City Engineer.
5. 
Design of Local Drainage Systems.
a. 
Runoff calculations:
Computation of stormwater runoff for drainage areas less than 200 acres shall be by the Rational Method, which is based on the principle that the maximum rate of runoff from a given drainage area for an assumed rainfall intensity occurs when all parts of the area are contributing to the flow at the point of discharge. The design of storm drainage improvements within the City of Midlothian shall be based on the Modified Rational Method formula.
1. 
The formula for calculating flows in this manner is:
Q = CACIA, where
Q is the storm flow at a given point (in cubic feet per second, ("cfs"));
C is a dimensionless coefficient of runoff representing the ratio of runoff to rainfall. Coefficient values to be used are listed below in Section 6.16.5.b.
I is the average intensity of rainfall for a period equal to the time of flow from the farthest point of the drainage area to the first inlet point on the storm sewer (in inches per hour, ("in/hr"));
A is the area tributary to the design point (in acres); and
CA is the antecedent precipitation factor, values to be used in this formula are shown in Table 6-3.
Table 6-3. Antecedent Precipitation Factor "CA"
Recurrence Interval
(Years)
CA
2 to 10
1.0
25
1.1
50
1.2
100
1.25
NOTE: The product of (C)(CA) should not exceed 1.0
2. 
For drainage areas in excess of 200 acres where the use of the Modified Rational Method does not provide reliable results, a unit hydrograph method shall be used. The use of a unit hydrograph calculation shall be based upon standard and accepted engineering principles normally used in the profession, subject to the approval of the City Engineer. The unit hydrograph method shall be based upon fully developed watershed conditions and not the flows calculated in the Federal Emergency Management Agency (FEMA) flood insurance studies which are based upon existing watershed conditions.
3. 
Circumstances that may require the use of a unit hydrograph method include sizing open channels, reclaiming floodplains, creating lakes or building other types of drainage-related facilities on major drainage courses. The detention effects of large regional detention facilities can be taken into account in unit hydrograph methods.
b. 
Runoff coefficient:
Federal Highway Administration (FHWA) runoff coefficients using the Rational Method developed for various surface conditions shall be used in design to represent fully developed conditions, based on the most recent City land use map. A runoff coefficient of not less than 0.6 must be used for areas not covered by the proposed land use maps or current City zoning.
Description of Area
C
Lawns
Sandy soil, flat, 2%
0.10
Sandy soil, average, 2 - 7%
0.15
Sandy soil, steep, > 7%
0.20
Clay soil, flat, 2%
0.17
Clay soil, average, 2 - 7%
0.22
Clay soil, steep, > 7%
0.35
Unimproved areas
Agricultural
0.30
Forest/wooded
0.15
Business
Downtown areas
0.95
Neighborhood areas
0.70
Residential
Single Family (1/8 acre lots)
0.65
Single Family (1/4 acre lots)
0.60
Single Family (1/2 acre lots)
0.55
Single Family (1+ acre lots)
0.45
Multi-Family Units, (Light)
0.65
Multi-Family, (Heavy)
0.85
Commercial/Industrial
Light areas
0.70
Heavy areas
0.80
Parks, cemeteries
0.25
Playgrounds
0.35
Railroad yard areas
0.40
Streets
Asphalt and Concrete
0.95
Brick
0.85
Drives, walks, and roofs
0.95
Gravel areas
0.50
Graded or no plant cover
Sandy soil, flat, 0 - 5%
0.30
Sandy soil, flat, 5-10%
0.40
Clayey soil, flat, 0 - 5%
0.50
Clayey soil, average, 5 - 10%
0.60
c. 
Rainfall intensity-duration-frequency:
The following table setting forth the rainfall intensity-duration-frequency ("IDF") data for Ellis County, Texas shall be used in making the calculations pursuant to this Section 6.16.5. This table has the data for durations ranging from 5 minutes to 24 hours with average return periods of 1, 2, 5, 10, 25, 50, and 100 years. Point rainfall intensities can also be calculated using the equation below:
I = b/(Td+d)e
I = Point rainfall intensity (in/hr)
Td = Duration of rainfall in minutes
b,d,e = Coefficients for IDF data as determined using Table below
Rainfall Intensity-Duration-Frequency Data for Ellis County
Return Period (Years)
Coefficient
1
2
5
10
25
50
100
e
0.84002
0.81147
0.80992
0.80183
0.78513
0.78190
0.76959
b
51.103
54.710
74.075
83.862
92.418
104.449
110.819
d
10.0
10.0
13.0
14.0
14.0
15.0
15.0
Hours
Minutes
Rainfall Intensity (inches per hour)
0.083
5
5.25
6.08
7.13
7.91
9.16
10.04
11.05
0.166
10
4.13
4.81
5.84
6.56
7.62
8.43
9.31
0.25
15
3.42
4.01
4.98
5.64
6.57
7.31
8.09
0.333
20
2.94
3.46
4.36
4.96
5.80
6.48
7.18
0.416
25
2.58
3.06
3.89
4.44
5.21
5.84
6.48
0.5
30
2.31
2.74
3.52
4.03
4.74
5.32
5.92
0.583
35
2.09
2.49
3.22
3.70
4.35
4.90
5.46
0.666
40
1.91
2.29
2.97
3.42
4.03
4.55
5.07
0.75
45
1.76
2.12
2.76
3.19
3.76
4.25
4.74
0.833
50
1.64
1.97
2.58
2.99
3.53
3.99
4.46
0.916
55
1.53
1.85
2.43
2.81
3.33
3.77
4.21
1
60
1.44
1.74
2.29
2.66
3.15
3.57
4.00
2
120
0.86
1.05
1.41
1.65
1.98
2.26
2.54
3
180
0.62
0.77
1.04
1.23
1.48
1.69
1.92
6
360
0.36
0.45
0.61
0.73
0.88
1.01
1.16
12
720
0.20
0.26
0.35
0.42
0.52
0.60
0.69
24
1440
0.11
0.15
0.20
0.24
0.30
0.35
0.41
The intensity, I, in the formula Q = CACIA is determined from these curves by arriving at a time of concentration and adapting a storm frequency upon which to base the drainage improvements.
1. 
Time of concentration:
The time of concentration, which is the longest time that will be required for a drop of water to flow from the furthest point of the drainage area to the point of concentration. Time of concentration consists of the time required to flow overland plus the time required to flow in the storm drainage facility. A minimum time of concentration of twenty (20) minutes shall be used for parks and open spaces. A minimum time of concentration of fifteen (15) minutes shall be used for residential areas. A minimum time of concentration of ten (10) minutes shall be used in industrial, commercial and mercantile areas. A nomograph, shown on Plate 1, is attached for estimating the time of concentration.
Plate No. 1
2. 
Storm frequency:
Recommended design storm frequencies for the storm drainage improvements in the City of Midlothian are shown in Table 6-4 as follows:
Table 6-4
Type of Facility
Description of Area to be Drained
Recommended Maximum Time or Concentration (minutes)
Recommended Design Frequency
(years)
Storm sewers with inlets on grade and recessed
Residential
30
10
Storm sewers draining low point inlets
Any type of area
30
25
Culverts, Bridges, Channels and Creeks
Any type of area less than 100 acres
30
45
Culverts, Bridges, Channels and Creeks
Any type of area greater than 100 acres but less than 1,000 acres
45
50
Culverts, Bridges, Channels and Creeks
Any type of area greater than 1,000 acres
60
50
In connection with the design of facilities such as Low Point Inlets, Culverts, Bridges, Channels and Creeks shown in Table 6-4, the discharge for a 100-year return frequency storm and the resulting possible damages therefrom shall be evaluated to determine if said damages are sufficient to warrant the enlargement of the planned facility. In any areas where stormwater runoff concentrates at low points of grade or where discharge in excess of the design discharge flows across private property, the following information shall be shown:
(a) 
The 100-year design discharge.
(b) 
The depth of inundation of this discharge.
(c) 
An evaluation of the possible damages resulting from the above information.
(d) 
Area:
The area used in determining flows by the "Modified Rational Formula" shall be calculated by subdividing a map into drainage areas within the basin contributing stormwater runoff to the system.
(e) 
Spread of water:
During the design storm, the quantity of stormwater that is allowed to collect in the streets before being intercepted by a storm drainage system is referred to as the "spread of water." In determining the limitations for carrying stormwater in the street, the ultimate development of the street shall be considered. The use of the street for carrying stormwater shall be limited to the following.
SPREAD OF WATER
(i) 
Arterials. One traffic lane on each side to remain clear.
(ii) 
Major Collectors. Two traffic lanes to remain clear.
(iii) 
Minor Collectors. One traffic lane to remain clear.
(iv) 
Local streets. Six (6) inch depth of flow at curb or no lanes completely clear.
(v) 
The capacity of straight crown streets can be determined from Plate 2. Plate 2 applies to all street widths having a straight cross-slope varying from 1/8 inch per foot to 1/2 inch per foot. 1/4-inch per foot cross-slopes shall be used unless prior approval is granted by the City.
(vi) 
Arterial or collector streets shall not be crossed with surface drainage. At any intersection, only one street shall be crossed with surface drainage and this shall be the lower classified street.
(f) 
Storm sewer design:
Stormwater in excess of that allowed to collect in the streets shall be intercepted in inlets and carried away in a storm sewer system. Storm sewer capacity shall be calculated by Manning's formula:
Q = 1.486/n AR 2/3S 1/2 where:
Q is the discharge in cubic feet per second;
A is the cross-sectional area of flow in square feet;
R is the hydraulic radius in feet;
S is the slope of the hydraulic gradient in feet per foot;
n is the coefficient of roughness (n = .013 for new concrete pipe)
(i) 
A storm drainage conduit must have sufficient capacity to discharge a design storm with a minimum of interruption and inconvenience to the public using streets and thoroughfares. The size of the conduit is determined by accumulating runoff from contributing inlets and calculating the slope of a hydraulic gradient from Manning's Equation.
(ii) 
To determine the capacity of specific inlets, Plates 3 through 6 shall be used. In using the plates for the selection of inlet sizes, care must be taken where the gutter flow exceeds the capacity of the largest available inlet size. Inlets shall be sized to intercept all flow in the approaching gutter, for the design storm, where possible.
(iii) 
Beginning at the uppermost inlet on the system, the hydraulic gradient for the selected conduit size shall be plotted between each contributing inlet to ensure that the selected conduit will carry the design flow at an elevation below the gutter profile. At each point where an inlet lateral enters the main conduit, the hydraulic gradient of the storm sewer must be 1.5 feet below the gutter grade.
(iv) 
At the discharge end of the conduit (generally a creek or stream) the hydraulic gradient of the creek for the design storm must coincide with the gradient of the storm drainage conduit. The hydraulic gradient of the creek or stream for the design storm can be calculated by use of the HEC-2 Computer Program.
(v) 
Concrete pipe conduit shall be used to carry the stormwater. Manning's Equation shall be used to determine the various hydraulic elements including the pipe size, the hydraulic gradient, capacity of the conduit and the velocity.
(vi) 
Storm sewer pipe sizes shall be so selected that the average velocity in the pipe will not exceed fifteen (15) feet per second nor less than two and one-half (2.5) feet per second.
(vii) 
Storm sewer systems shall be installed in all areas when either of the following apply:
1. 
The runoff can be carried in a pipe of sixty inches (60") in diameter or smaller; or
2. 
Where it is necessary for the protection of adjacent facilities that the stormwater be carried in an enclosed facility.
PLATE NO. 2
PLATE NO. 3
PLATE NO. 4
PLATE NO. 5
PLATE NO. 6
(g) 
Open channel design:
Stormwater runoff in excess of that allowed to collect in the streets in developed areas and runoff in undeveloped areas may be carried in open channels (not in the street right-of-way). Open Channel capacity shall be calculated by Manning's Formula and roughness coefficients shall be as follows:
Type of Lining
Roughness Coefficient "n"
Maximum Permissible Mean Velocity
Earth (Bermuda Grass)
0.035
5 ft. per sec.
Concrete Lined
0.015
12 ft. per sec.
Weathered Rock
0.030
8 ft. per sec.
(i) 
Open channels shall be constructed with a trapezoidal cross-section and shall have side slopes no steeper than 4:1.
(ii) 
Should it be necessary to construct a channel with side slopes steeper than 4:1, security fencing of a minimum of six feet (6') in height shall be constructed on both sides of the channel.
(iii) 
Reinforced concrete lined channels shall conform to the following:
1. 
Channels draining an area with a "CA" factor of 250 or less shall be lined with reinforced concrete in a manner which will contain the design frequency storm plus one foot (1') of freeboard within the concrete lining.
2. 
Channels draining an area with a "CA" factor of more than 250 but less than 500 shall be concrete lined to contain the runoff from a five (5) year return frequency storm with the balance of the required design frequency storm contained within grassed slopes no steeper than three (3) horizontal to one (1) vertical and with a minimum of one foot (1') freeboard.
3. 
Channels draining an area with a "CA" factor of more than 500 but less than 2,000 shall be constructed with a reinforced concrete pilot channel not less than twelve feet (12') in width and having at least six-inch (6") curbs, a four-inch (4") depressed invert, and an appropriate edge protection as accepted by the City Engineer. The remainder of the channel shall consist of earthen side slopes with proper vegetative cover on slopes not steeper than 3 to one.
(iv) 
Natural channels may be preserved when draining an area having a "CA" factor of more than 2,000 or when the developer desires to preserve natural channels within his addition for purposes of aesthetics and/or open space. An application for preservation of a natural channel shall be submitted to and approved by the City prior to approval of the preliminary plat. This application shall contain the following information furnished by the developer's engineer.
1. 
Topographic, hydrologic and hydraulic information sufficient to properly evaluate the proposal and showing that: (i) before any site work has begun, all land having an elevation below the fifty (50) year return frequency flood elevation is contained within an easement dedicated to the public for the purpose of providing drainage; (ii) the channel easement has a minimum hydraulic capacity to accommodate a fifty (50) year return frequency storm based on a fully developed watershed; (iii) that all minor channel improvements, such as reshaping, realignment, etc., are protected with sodding, backsloping, cribbing, or other bank protection that is designed and constructed to control erosion from the fifty (50) year return frequency flood. An analysis shall also be made to determine the effects of the 100-year flood.
2. 
When the natural channel to be preserved is one which has had Floodplain Information developed the floodplain boundary limits of the 100-year return frequency storm shall be as shown.
The subdivider shall dedicate a right-of-way on all open channels of sufficient width to provide for excavation of the open channels of proper width, plus 10 feet on each side to permit ingress and egress for maintenance.
(h) 
Culvert design:
(i) 
At locations of creek crossings with proposed roadway improvements, it is sometimes necessary to receive and transport stormwater under the roadway in culverts. The quantity of flow shall be determined by the Modified Rational Formula, and the capacity of the culvert shall be calculated by Manning's Formula.
(ii) 
Design of culverts shall include the determination of upstream backwater conditions as well as downstream velocities and flooding conditions. Consideration shall be given to the discharge velocity from culverts, and the following limitations are allowed.
CULVERT DISCHARGE - VELOCITY LIMITATIONS
Culvert Discharging on to
Maximum Allowable Velocity
(fps)
Earth (Bermuda Grass)
5
Paved or riprap apron
12
Shale
6
Rock
8
Generally, all culverts shall be designed with a free outfall and the following head losses shall govern the design of the culvert:
1. 
Frictional Head Loss hf = Sfl
hf = Sfl where
Sf = Slope of frictional gradient in feet per foot
L = Length of culvert in feet
2. 
Head Loss due to change in velocity
hv = v22/2g - v12/2g where
v2 = Velocity in culvert;
v1 = Velocity in channel above culvert;
g = Acceleration due to gravity
3. 
Head Loss at upstream entrance to culvert due to entrance and change in:
he/2g = v22 where v1 is equal to or less than six (6) feet per second
he = v22/2g-0.5 v12/2g where v1 is greater than six (6) feet per second section
(i) 
Stormwater mitigation:
Stormwater detention facilities to reduce runoff rates will be required due to a change in land use resulting in an increase in runoff or inadequate storm drainage systems. Inadequate storm drainage systems to be considered include, but are not limited to existing downstream structures, channels and identifiable flood prone areas.
(i) 
Detention facilities shall be in compliance with all applicable design requirements of local, state or federal ordinances, laws or regulations, including the regulations for dam safety of the TCEQ and environmental regulations of U.S. Army Corps of Engineers 404 permitting requirements.
(ii) 
Stormwater detention basins are used to temporarily impound (detain) excess stormwater, thereby reducing peak discharge rates. These basins are used to provide the detention required to reduce the proposed peak discharge rate down to at least that of the existing conditions to satisfy the following requirements:
1. 
Compliance with City ordinances.
2. 
Preservation of existing floodplains along major creeks.
3. 
Prevention of overloading inadequate downstream storm drainage facilities.
4. 
Prevention of erosive conditions in watercourses.
(iii) 
The following general criteria serve as minimum requirements for detention pond design in the City of Midlothian:
1. 
The 100-year frequency storm for ultimate development watershed conditions must be used to determine the volume of detention storage required. In addition, the outlet structure must be designed such that the peak discharge is reduced to pre-development flow rates or less as specified below:
a. 
Discharge from the 2-year design storm shall not exceed the pre-development flow of a 1-year storm;
b. 
Discharge from the 5-year design storm shall not exceed the pre-development flow of a 2-year storm;
c. 
Discharge from the 10-year design storm shall not exceed the pre-development flow of a 5-year storm;
d. 
Discharge from the 25-year design storm shall not exceed the pre-development flow of a 10-year storm;
e. 
Discharge from the 50-year design storm shall not exceed the pre-development flow of a 25-year storm; and
f. 
Discharge from the 100-year design storm shall not exceed the pre-development flow of a 100-year storm.
2. 
The outlet structure shall consist of a series of openings, baffles, orifices, etc., in order to throttle the flow from the pond. The use of any type of culvert or weir structure without the use of openings, baffles, orifices, etc. is not permitted without the written approval of the City Engineer.
3. 
A non-erodible emergency spillway or overflow area must be provided at the maximum 100-year pool level.
4. 
The outflow structure must discharge flows into the natural stream or unlined channels at a non-erosive rate.
5. 
Detention basins to be excavated must provide positive drainage through the pond with a minimum slope of 0.30%. The steepest side slope permitted around the detention pond is 4:1.
6. 
Earthen embankments used to impound a required detention volume must have a minimum top-width of 12 feet, must contain a non-permeable core, and must be based on a geotechnical investigation for the site. The geotechnical investigation must be performed by a licensed engineer. Earthen embankments higher than six feet must conform to 30 Texas Administrative Code, chapter 299 and other applicable dam safety requirements.
7. 
Security fencing with a minimum height of six feet may be required to encompass the detention storage area if the location, velocity, depth, or slopes justify restricted access to the general public as determined by the City Engineer. The fence must be designed to allow access for maintenance, while not restricting storm water flow into or out of the detention basin.
8. 
A maintenance ramp must be provided for equipment access in detention basin design for periodic desilting and debris removal. The slope of the ramp must not exceed 6H:1V, and the minimum width must be 12 feet.
9. 
Basins with permanent storage must include dewatering facilities to provide for maintenance.
10. 
The design of detention facilities must include provisions for collecting and removing sediment deposited after collecting and releasing stormwater.
11. 
A non-erodible pilot channel must be provided to convey runoff from entry points of concentrated flow into the pond to the outlet structure of the pond during low flow conditions. Erosion protection must be provided adjacent to the pilot channel to prevent undermining of the pilot channel due to scour. This type of channel is not required for permanent pool basins (i.e. wet ponds).
12. 
The developer or owner is required to enter into a Detention Facility Maintenance Agreement with the City prior to receiving final acceptance of the public improvements within the development or before receipt of a certificate of occupancy.
(Ordinance 88-14, sec. 6.16, adopted 7/26/88; Ordinance 98-11, sec. 1(D), adopted 2/10/98; Ordinance 2001-39, sec. 1(5), adopted 8/28/01; Ordinance 2001-39, sec. 1(5)–(10), adopted 8/28/01; Ordinance 2004-17 adopted 4/6/04; Ordinance 2017-15 adopted 3/28/17; Ordinance 2025-64 adopted 11/11/2025)
1. 
General:
The design and construction of the water distribution system to serve the development shall be in accordance with good engineering principles, with the Rules and Regulations for Public Water System as published by the Texas Department of Health (TDH), with the requirements of the State Board of Insurance and the City of Midlothian’s standards. No construction shall commence prior to the approval of the plans and specifications by the City Engineer and the appropriate state regulatory agency (when applicable).
All facilities shall be of sufficient size to provide adequate capacity for ultimate development and in accordance with the City’s Water Master Plan. Pipelines shall be sized to meet the domestic requirements plus an appropriate allowance for fire protection. The developer shall cause a hydraulic analysis to be performed on the development to ensure that minimum fire flow requirements will be met, unless this requirement is waived by the City Engineer and the City Fire Chief based on the availability of pertinent engineering-based data. For a residential subdivision, in addition to normal usage the minimum fire flow requirement is 1,000 gallons per minute at a residual pressure of 20 psi for a minimum duration of 60 minutes. Nonresidential developments shall meet the minimum requirements imposed by the current edition of the Fire Code for the City of Midlothian. The City reserves the right to require larger pipelines than those required for the proposed development. The design criteria for water demand shall be submitted to the City with the plans and specifications.
If the proposed subdivision is located beyond the area presently being served by the water distribution system, the developer shall be required to provide the off-site improvements necessary to transport water to the area being developed. Individual water wells for the lots will not be considered an acceptable method of serving the development.
2. 
Line Size:
The minimum pipeline size to serve residential areas shall be six (6") inches in diameter and the minimum pipeline size serving commercial, business, industrial, and multifamily shall be eight (8") inches. All water lines shall be looped with no dead-ends, unless otherwise approved by City Engineer. Dead-end lines shall be provided with a flush valve or fire hydrant at the end. Dead-end lines shall not exceed 1000 feet in length without prior approval of the City Engineer. Pipelines shall be sized to provide sufficient supply for fire flows in accordance with the minimum criteria of the State Board of Insurance and other governing authorities.
3. 
Pipe Material:
Water pipelines shall be ductile iron (polywrapped), polyvinyl chloride (PVC) C-900, C-905, C-909 or concrete steel cylinder. In general, all water pipelines shall be minimum Class 150. Class 200 shall be used when pressure exceeds 125 psi. Ductile iron pipe shall be a minimum Class 50 with a cement mortar liner. All pipe shall be new and approved by the Underwriters’ Laboratory and shall be acceptable to the Texas State Fire Insurance Commission for use in water distribution systems without penalty. PVC water pipe shall also bear the seal representing class of pipe.
4. 
Fittings:
All fittings shall be cast iron or ductile iron (polywrapped) and shall comply with American Water Works Association Standard Specification (AWWA) C110 or (AWWA) C111. Below grade fittings shall be either mechanical joint, push-on joint or flanged joints. Adequate thrust blocking shall be provided at all fittings. Above grade fittings shall be flanged joints. Concrete steel cylinder pipe fittings shall be of the same material as the pipe.
5. 
Fire Hydrants:
Fire hydrants shall be located at each street intersection and at intervals on the interior of each block. Spacing of fire hydrants in single-family residential areas shall not be over 400 feet apart along the street. Spacing of fire hydrants in the commercial, industrial or high density residential areas shall not be over 300 feet apart along the street. In all cases, the fire hydrant shall be within 500 feet of any portion of a building. If special conditions exist, the Fire Chief may require additional hydrants for fire protection.
All fire hydrants shall be installed with a minimum six (6) inch lead off a minimum six (6) inch main. There shall be a gate valve installed between the main and hydrant. Fire hydrants shall be located between three (3) and five (5) feet back of the curb, or if in a subdivision not requiring curbs, within 3-5 feet of right-of-way abutting property.
All fire hydrants shall be three-way feed with one pumper nozzle of 4.5 inches and two hose nozzles of 2.5 inches (NST threads). The operating nut shall be a 1-1/2 inch pentagonal and shall open by turning to the left/counterclockwise.
Fire hydrants shall be painted to meet the City’s requirement for color code. In general, the fire hydrant will have a bright silver base (preferably “flynt aluminum”) with differing bonnet and cap color which corresponds to the main size it is located on as shown in the table.
Fire Hydrant Color Code
Main Size
Color of Bonnet and Cap
Private (All Sizes)
Red
6 inch
Silver
8 inch
Green
12 inch or larger
Blue
6. 
Gate Valves:
All gate valves shall be resilient seat gate valves. All gate valves sixteen (16) inches and larger shall be furnished with bypass valves. Valves shall open by turning counterclockwise and shall have a 2-inch operating nut.
Gate valves shall be located at intersections to allow the isolation of lines for repairs. Valves shall be placed so that not more than 50 lots will be out of service while a line is shut down for repair. All valves shall be installed in the vertical position with a valve box and cover centered over the stem. A two (2) foot square and six (6) inches thick concrete pad shall be constructed around the top of the valve box.
7. 
Testing and Sterilization:
All water pipelines shall be hydrostatically tested in accordance with the City’s standard specifications. The test shall include service lines, fire hydrants, flush valves, etc. and all testing shall be accomplished in the presence of a representative of the City of Midlothian. The developer shall be responsible for all expenses required to hydrostatically test the pipelines.
All facilities shall be flushed and sterilized. The developer will be required to submit samples to an approved laboratory for certification as being free of bacteria. A sample is required for each 1000 feet of main. The developer shall be responsible for sterilization and resterilization as necessary and all expenses associated with the sterilization. This shall be performed in the presence of a representative of the City Engineer.
8. 
Location and Installation:
All water mains shall be located under paving five feet from back of curb on the north/east side of the street. Installation shall be at the line and grade as shown on the plans. The mains shall have a minimum of 42 inches of cover in open areas. Water lines under existing streets and proposed streets shall have a minimum cover of 42 inches from the finish grade. Special attention shall be given to water lines in unimproved streets in order to provide for the future grading of those streets.
Water lines shall be embedded and backfilled as required by the City’s standard construction details. For trenches located in streets, the backfill shall be compacted to a minimum of 95% Standard Proctor Density. Jetting will not be allowed.
All bends, fittings, etc. shall have 2,000 psi concrete thrust blocking provided.
(Ordinance 88-14, sec. 6.17, adopted 7/26/88; Ordinance 98-11, sec. 1(D), adopted 2/10/98; Ordinance 99-11 adopted 2/23/99; Ordinance 2001-39, sec. 1(11)–(15), adopted 8/28/01; Ordinance 2004-17 adopted 4/6/04)
1. 
General:
The design and construction of the sewer collection system to serve the development shall be in accordance with good engineering principles, with the Design Criteria for Sewerage Systems as published by the Texas Department of Health (TDH) and with the City of Midlothian’s standards. No construction shall commence prior to the approval of the plans and specifications by the City Engineer and the appropriate State Regulatory agency.
All facilities shall be of sufficient size to provide adequate capacity for ultimate development. Sewer lines shall be sized to meet the peak-day dry-weather flow plus an appropriate allowance for inflow/infiltration. The minimum sewer pipeline size shall be six (6") inches in diameter. The City reserves the right to require a pipeline of a larger size than that required by the development. The design criteria and calculations shall be submitted to the City Engineer with the plans and specifications.
If the proposed subdivision is located beyond the drainage area presently being served by the sewage collection system, the developer shall be required to provide the off-site and on-site improvements necessary to transport the sewage from the area being developed. Any lift station, force main and/or gravity sewer pipe improvements required as a result of the proposed development shall be the developer’s responsibility. Septic type systems will be considered in accordance with current city ordinances and Ellis County regulations.
2. 
Pipe Size and Grades:
The minimum line size shall be six inches (6") in diameter. Sanitary sewer lines shall be designed to have a minimum mean velocity flowing full of 2.5 feet per second (fps). The minimum slope of the sewer lines shall conform to the minimums recommend[ed] by the TDH and maximum velocity shall not exceed 10 fps.
3. 
Pipe Material:
Sanitary sewer pipe shall be polyvinyl chloride pipe (PVC-SDR 35), in accordance with the City’s standard specifications.
All pipe shall be new and approved by the Underwriters’ Laboratories, Inc. and the PVC pipe shall be colored green and bear the seal representing class of pipe.
4. 
Manholes:
Manholes shall be located at all intersections of sewer pipelines, changes in grade, changes in alignment and at distances not to exceed 500 feet. Manholes shall be constructed of precast reinforced concrete pipe or cast-in-place concrete. Brick manholes will not be allowed. Where PVC pipe enters manholes, a resilient pipe to manhole connector or gasket shall be used to provide a watertight connection.
All manholes shall have 24-inch standard manhole rings and covers. All covers shall have pick bars and should be stamped CITY OF MIDLOTHIAN SANITARY SEWER per the Standard Construction Details. Watertight rings and covers shall be furnished in areas located within the 100-year floodplain, or as directed by the City Engineer.
5. 
Drop Manhole:
Drop manholes shall be used at locations where the elevation of the incoming sewer line is 2.0 feet or greater from the elevation of the outgoing line. Construction shall be the same as the standard manhole. The drop piping shall be PVC-SDR 35 pipe.
6. 
Cleanouts:
Cleanouts shall be constructed at the upper end of all sewer mains. Cleanouts shall be constructed of the same material and same size as the sewer main. The top shall have a cast iron boot with cover. A two-foot square by 6-inch thick, 2,000 psi concrete pad shall be placed around this boot.
7. 
Force Main:
Force main materials and installation shall be in accordance with Section 6.15 [6.17], Water System, and as directed by the City Engineer and a Regulatory Agency (when applicable).
8. 
Lift Stations:
Lift stations shall be designed in accordance with the criteria of the Texas Department of Health. Design data will be submitted and approved on a case-by-case basis by the City Engineer.
9. 
Testing:
All sewer pipe shall have deflection tests performed on them. This test shall be conducted after the final backfill has been in place at least 30 days. No pipe shall exceed a deflection of 5 percent. Test shall be performed using a “go - no go” mandrel.
All sewer lines shall be tested for infiltration/exfiltration. The preferred method of testing the pipe would be by using the “Low-Pressure Air Test” in accordance with City of Midlothian Standard Construction Details. All testing shall be conducted in the presence of a representative of the City Engineer. All expenses for this work shall be the developer’s responsibility.
10. 
Location and Installation:
All sewer mains in local streets shall be constructed at the centerline of the street. In collector and arterial streets, the sewer line shall be located a minimum of three (3) feet back of curb or as directed by the City Engineer. Sewer mains shall be constructed to the line and grade as shown on the plans. Horizontal curves shall not be accomplished by mechanical means and shall be achieved by pipe flexure and not joint deflection. The minimum radius for PVC sewer pipe shall be determined using the following Formula:
R = 300 x D
Where
R
=
minimum allowable radius of curvature
D
=
pipe diameter
(R and D are in same dimensional units)
Manholes shall be located at lot lines whenever possible. Manholes are not to be located in the bottom of bar ditches or in drive approaches.
Sewer lines shall be embedded and backfilled as required by the City’s standard construction details. For trenches located in streets, the backfill shall be compacted to a minimum of 95% Standard Proctor Density. Jetting will not be allowed.
11. 
Adequate Sanitary Sewer Capacity
a. 
No subdivision shall be finally approved unless assurances have been provided by the subdivider that the subdivision will be served by adequate collection and treatment facilities for sanitary sewage disposal.
b. 
The capacity of the existing or planned collection mains and treatment facilities to serve the subdivision shall be adequate to accommodate expected sanitary sewage flows generated by the development under engineering design standards specified by the City Engineer, taking into account existing and future connections to the collection mains and treatment facilities to which the lots in the subdivision are to be connected.
12. 
Determination of Capacity of Sewer Facilities.
a. 
Carrying capacity determination.
The City Engineer, using accepted engineer standards and practices, shall determine the carrying capacity of each sanitary sewer line operated by or in behalf of the City. Capacities shall be determined for each segment of a sewer collection line, and each collection facility appurtenant to such line, such as a lift station that potentially and separately limits the potential of a segment of the collection facility of which it is a part.
b. 
Reserved capacity.
The City Engineer, using accepted engineer standards and practices, shall determine the initial reserved capacity of each facility for which carrying capacity has been determined in section a. Reserved capacity for a given facility shall be determined initially by estimating the consumption of capacity attributable to existing connections and future connections attributable to development of lots in approved final plats. The City Engineer shall regularly update reserved capacity based upon approval of developments, as provided in section d.
c. 
Potential consumption of capacity.
The City Engineer, using accepted engineer standards and practices, shall determine the initial potential consumption of capacity of each facility for which carrying capacity has been determined in subsection a. Potential consumption of capacity for such facility shall be determined initially by adding to the reserved capacity of the facility the estimated additional consumption of capacity attributable to development of lots in approved preliminary plats for which no final plat has been approved. The City Engineer shall regularly update potential consumption of capacity based upon approval of developments, as provided in subsection d.
d. 
Capacity update.
The City Planning Director shall convey information to the City Engineer concerning the land uses and number of lots for each proposed or approved final and preliminary plat. The City Engineer shall regularly update his estimates of reserved capacity and potential consumption of capacity utilizing such information.
e. 
Overcapacity determination.
If the City Engineer upon his initial determination of carrying capacity, reserved capacity and potential consumption of capacity finds that one or more sanitary sewer mains has reached potential overcapacity, or actual overcapacity or 85% of carrying capacity, as described in subsections 15 and 16, he shall report such fact to the City Manager, who shall institute public notification. Thereafter, the procedures in subsections 15 or 16, as the case may be, shall govern the review of subdivision plats.
13. 
Reservation of Capacity.
a. 
Reserved status.
Except as provided in this section, approval of a final plat by the City Planning and Zoning Commission constitutes the City’s determination that capacity in the sewer lines serving the subdivision is reserved, so that each lot subject to the final plat may be connected to the City’s sewer lines; provided, however, that impact fees shall be paid at the time of such final plat approval pursuant to subsection d. Each lot in a final plat which has been approved for connection to a sewer facility with remaining capacity by the Commission shall be deemed to have reserved status in the City’s sewer facilities serving the lot. Each lot within a final plat that was approved prior to the effective date of this section shall be deemed to have reserved status.
b. 
Designation of status.
In the event a final plat application proposes development that, if connected to the City’s sewer lines, would result in the overcapacity of such facility or facilities, the Commission’s approval of the final plat shall be subject to a notation that capacity in affected sewer facilities is not reserved for all or a portion of the lots in the plat. In such event, a plat note shall be attached indicating which lots subject to the final plat do not have reserved status. Such lots shall be deemed to have non-reserved status.
c. 
Connections prohibited.
In no event shall any lot or land use be connected to a sewer line that is overcapacity, nor shall connection be made to any lot that is subject to a plat note or other designation of non-reserved status, unless unreserved capacity remains in the line or lines to which connection is proposed.
d. 
Payment of impact fees.
No lot finally platted after the effective date of this ordinance shall acquire reserved status nor shall any finally platted lot be connected to the affected sewer facility until impact fees have been paid for such lot. An owner seeking reserved status for a proposed subdivision after the effective date of this ordinance shall execute an agreement for payment of impact fees at the time of final plat approval.
14. 
Capacity Documentation.
a. 
Factors for calculation.
In calculating the carrying capacity, potential overcapacity or overcapacity of a sewer facility, the City Engineer shall take into account (1) the size and slope of gravity mains, (2) the size of force mains, (3) the pump capacity and (4) the size of wet wells.
b. 
Identification of facilities and area affected.
In making any determination concerning the capacity or overcapacity of a sewer facility, the City Engineer shall identify with particularity the line, line segment or facility affected, and shall outline the property potentially served by such facility.
c. 
Conventions.
In making a declaration of potential overcapacity or overcapacity of a sewer line or transmission facility, the City Engineer may establish reasonable thresholds below the carrying capacity of the facility in order to avoid partial designation of lots in proposed subdivisions for reserved status.
15. 
Declaration of Potential Overcapacity.
a. 
Potential overcapacity determination.
Upon determining that any sewer facility is at or beyond carrying capacity, based upon the potential consumption of capacity of such facility, either upon initial determination of potential consumption or following an update, and after documenting his finding in the manner provided in subsection 14, the City Engineer shall inform the City Manager and the Planning Director of such determination.
b. 
Public notice.
The City Manager shall cause to be published notice of such potential overcapacity in a newspaper of general circulation. The notice shall describe the sewer line(s), line segment(s) or other facilities affected by the determination.
c. 
Preliminary plat procedures.
Following publication of notice of potential overcapacity, every preliminary plat thereafter approved shall be subject to a condition that a potential overcapacity in one or more sewer lines has been reached, and that the City cannot assure that final plat approval will result in reserved status for the lots in the subdivision.
d. 
Potential overcapacity for part of subdivision.
Where a proposed preliminary plat would result in a potential overcapacity for one or more sewer facilities, the plat shall be subject to a condition that a potential overcapacity in one or more sewer lines has been reached for a portion of the lots proposed in the plat, and that the City cannot assure that final plat approval for such lots will result in reserved status for all lots in the subdivision.
16. 
Overcapacity Declaration.
a. 
Overcapacity determination.
Upon determining that any sewer facility is at or beyond carrying capacity or at 85% of carrying capacity, based upon estimates of reserved capacity for such facility, either upon initial determination of reserved capacity or following an update, and after documenting his finding in the manner provided in subsection 14, the City Engineer shall inform the City Manager and the Planning Director of such determination.
b. 
Public notice.
The City Manager shall cause to be published notice of such overcapacity in a newspaper of general circulation. The notice shall describe the sewer line(s), line segment(s) or facilities affected by the determination of overcapacity. The notice also may announce a public hearing in the manner provided in subsection 17.
c. 
Final plat procedures.
Following publication of notice of overcapacity, or, in the event a moratorium is adopted as provided in subsection 17, every final plat thereafter approved shall be subject to a designation of non-reserved status for the lots contained in the plat that are to be served by the facility that is overcapacity, subject to appeal as provided in subsection f [sic]. Lots bearing such designation shall not be connected to any sewer facility that is overcapacity.
d. 
Partial overcapacity.
Where a proposed final plat would result in overcapacity for one or more sewer facilities, a portion of the lots subject to the final plat shall be designated for reserved status upon plat approval and the portion of the lots that cannot be adequately served shall be designated for non-reserved status. Lots in the final plat bearing a non-reserved designation shall not be connected to any sewer facility that is overcapacity.
e. 
Queuing of plats for reserved status.
Following publication of notice of overcapacity, or as authorized following adoption of a moratorium pursuant to subsection 17, approved final plats shall qualify for reserved status in the event capacity is added or prior reserved capacity is released, according to the order in which the final plats have been approved, provided that wastewater impact fees for the development shall be paid at the time the final plat is approved.
17. 
Public Hearing and Ordinance.
a. 
Effective date.
This section of the ordinance takes effect on September 1, 2001.
b. 
Public notice.
Whenever the City Engineer determines that a sewer facility has reached 85% of its carrying capacity based on the reserved status of finally platted lots, he shall inform the City Manager, who shall cause to be published notice of public hearings to consider adoption of a moratorium arising from a shortage of sewer facilities. The notice shall be published in a newspaper of general circulation in the City on the fourth day before the first public hearing. The notice shall identify the time and place of a public hearing before the Planning and Zoning Commission and a public hearing before the City Council concerning the moratorium.
c. 
Temporary suspension of permits.
On the fifth business day after the date of publication of the notice of public hearings on the moratorium, no application for final plat approval shall be further processed or approved nor shall any building permit be further processed or issued for construction of any structure on a lot that does not have reserved status on such date, nor shall any connection to an affected sewer facility be made to such lot. The temporary suspension on processing and approval of final plat applications and building permits expires if the City Council does not enact an ordinance imposing such suspension within the time period prescribed in subsection e.
d. 
Public hearings.
The Planning and Zoning Commission shall conduct the initial public hearing and shall make its recommendation to the City Council concerning adoption of a moratorium. The City Council shall conduct a second public hearing to consider the adoption of a moratorium ordinance.
e. 
Moratorium ordinance.
Based upon public testimony, the recommendation of the City Engineer and the recommendation of the Commission, the Council shall determine whether to adopt an ordinance suspending the processing or issuance of building permits for lots without reserved status pending addition of capacity to the affected sewer facilities. The ordinance shall be adopted by the City Council on two readings within twelve (12) days of the public hearing conducted by the Commission. The readings of the ordinance shall be separated by at least four (4) days. The ordinance shall incorporate the findings mandated by subsection f. The ordinance also shall expressly provide whether and the extent to which final plat applications may be approved during the pendency of the moratorium.
f. 
Findings required.
The City Engineer shall prepare a report to the Commission and the City Council that identifies each sewer facility that has reached the threshold specified in subsection a. [subsection b.] For each such facility, the report shall document the carrying capacity of the facility, the number of and consumption of capacity attributable to the actual connections utilizing the facility, the reserved capacity of the facility, the potential overcapacity of the facility, the amount of impact fee revenues collected that are earmarked for construction of improvements that add capacity to the facility, the capacity of any improvements which a subdivider has agreed to construct, and the time period necessary to alleviate the overcapacity of the facility. Such evidence, as may be modified based upon evidence obtained at the public hearings, shall be incorporated as the Council’s findings of fact within any ordinance suspending the processing or issuance of building permits under subsection e.
g. 
Duration of moratorium ordinance.
A moratorium ordinance adopted pursuant to this section expires on the 120th day following the date of adoption, unless the Council extends the moratorium utilizing the procedures in subsection h.
h. 
Extension procedures.
The Council may extend a moratorium suspending the processing and approval of final plat applications or building permits arising out of a shortage of sewer facilities by publishing a notice of a public hearing on such proposed extension in a newspaper of general circulation within the City at least fifteen (15) days prior to the date of the public hearing and at least twenty (20) days before the expiration of the moratorium. The City Council shall conduct the public hearing on the proposed moratorium extension. If the Council determines that the moratorium should be extended in whole or in part, it shall adopt an ordinance that incorporates written findings identifying the problem requiring the need for the extension, describing the progress made to alleviate the problem and specifying a definite duration for the extension of the moratorium. The extension ordinance shall identify any sewer facilities which are to be released from the moratorium based on addition of capacity and shall provide for complete or partial release in the event capacity is added to one or more sewer facilities during the pendency of the moratorium.
i. 
Relief procedures.
(1) 
An applicant for approval of a final plat or a building permit affected by the moratorium may request a waiver from the moratorium from the City Council by submitting a written petition claiming that he has a vested right to the plat or permit under Tex. Loc. Govt. Code ch. 245 or at common law, or pursuant to a right acquired under an approved development agreement. The Council shall act upon the waiver request within ten (10) days after receiving the written request.
(2) 
The Council shall release an applicant from the moratorium who proposes to build capital improvements that add capacity to the affected facility, upon construction and acceptance of such improvements, in the manner provided in subsection 19.a.
18. 
Release of Capacity Reservations.
a. 
Termination of reserved status.
Finally platted lots having reserved status shall retain such status for a period of three years following the date of final plat approval, after which reserved status shall terminate, unless extended by the City Manager or the City Manager’s designee for good cause upon written request of the lot owner, which extension shall not exceed ninety (90) days in duration. If a building permit has been issued for any lot prior to the expiration of reserved status and remains in effect on the date such status would otherwise terminate, but connection has not yet been made to sewer lines serving the property, reserved status shall be extended automatically until the building permit expires. The date on which reserved status terminates for any lot shall be considered the date on which lots that have applied for reserved status pursuant to subsection 16.e may qualify.
b. 
Release of capacity.
Upon termination of reserved status for lots subject to an approved final plat, the capacity formerly reserved shall be released for use by lots that have applied for reserved status pursuant to subsection 16.e, in the order in which such final plats were approved. The City shall notify the owners of finally platted lots who have applied for reserved status and who can be served by the released capacity that they have attained reserved status. Upon such notification, such lots shall be deemed released from any applicable moratorium.
c. 
Termination of attained reserved status.
Reserved status for finally platted lots that have been attained as a result of the release or addition of capacity shall terminate three years from the date it was attained. The date on which attained reserved status terminates shall be considered the date by which such lots qualify for reserved status pursuant to subsection 16.e.
19. 
Declaration of Capacity
a. 
Determination of added capacity.
Upon addition of capacity to a sewer facility resulting from improvements to the facility, the City Engineer shall determine the new carrying capacity of the facility, the extent to which finally platted lots on non-reserved status can be accommodated by the additional capacity, and whether a potential overcapacity still exists. If the improved facility can adequately provide service to all finally platted lots, the City Engineer shall declare that the overcapacity has been cured and report such fact to the City Manager. If the added capacity cannot serve all finally platted lots on non-reserved status, the City shall notify the owners of finally platted lots who can be served by the added capacity that they have attained reserved status in the manner provided in subsection b. The addition of capacity to a sewer facility subject to a moratorium imposed under subsection 17 may result in termination of the moratorium, in accordance with the provisions of the ordinance establishing the moratorium.
b. 
Public notice.
In the event the City Engineer makes a declaration of added capacity, the City Manager shall cause notice to be published in a newspaper of general circulation. The notice shall describe the sewer line(s), line segment(s) or other facilities affected by the determination of capacity, and whether a potential overcapacity still exists. Notice also shall be sent to any owner of a finally platted lot on non-reserved status who has requested notification in the event that capacity becomes available.
c. 
Developer-constructed improvements.
If, following a declaration of overcapacity pursuant to subsection 16, the owner of a finally platted subdivision agrees to construct improvements that add capacity to a sewer facility serving the property, such additional capacity shall be reserved for the subdivision notwithstanding the fact that other final plats have been approved prior to the final plat for which capacity is being added. Any capacity in excess of that needed to serve the lots in the subdivision shall be released for use in accordance with this section and allocated in the manner provided in subsection 16.e. Construction of sewer improvements shall be in accordance with all City design standards, including oversizing for and extension of facilities shown on the City’s approved master plans.
d. 
Development using temporary facilities.
Following a declaration of overcapacity pursuant to subsection 16, the owner of land that would be otherwise be served by the overcapacity facilities may temporarily utilize an on-site sewage disposal system. The temporary on-site sewage disposal system must meet all applicable codes and regulations for a permanent on-site sewage disposal system. Notwithstanding the requirements of Section 14-47 [sic] of the City Code of Ordinances, a temporary system authorized by this subsection may be permitted without the necessity of obtaining a waiver of connection requirements. An owner must comply with the annexation requirements of Section 14-47, Subchapter C. A temporary on-site sewage disposal system may be utilized for the duration of the period during which an overcapacity exists. Upon a declaration of capacity for the facilities to serve the property, the owner must cease utilizing the temporary on-site sewage disposal system and must comply with Section 14-47, within twelve months of the date of declaration unless otherwise allowed by the City. An owner who proposes to utilize a temporary on-site sewage disposal system must provide assurance that the lot or lots served by the system may be connected to the City’s sanitary sewer system. At the City’s option, such assurance based on current costs may be made by: (1) the owner installing sanitary sewer lines in accordance with applicable codes and regulations, for connection to the City’s sanitary sewer system; or (2) the owner providing financial security, by cash escrow, bond, or other instrument acceptable to the City Attorney for the installation of sanitary sewer lines for connection to the City’s sanitary sewer system.
Editor’s note–The user is directed to article 13.03 of the Code of Ordinances for regulations pertaining to sanitary sewer connection.
e. 
Plat notation removal.
The owner of a final plat that it is [sic] subject to a plat note designating all or a portion of the lots within the subdivision for non-reserved status may remove such notation through replat procedures set forth in section 4.17 [sic].
(Ordinance 88-14, sec. 6.18, adopted 7/26/88; Ordinance 98-11, sec. 1(D), adopted 2/10/98; Ordinance 2001-34, sec. 1(B), (C), adopted 8/14/01; Ordinance 2001-39, sec. 1(16)–(19), adopted 8/28/01; Ordinance 2004-17 adopted 4/6/04)
1. 
All services for utilities shall be made available for each lot in such manner so as to eliminate the necessity for disturbing the street pavement, curb, gutter, sidewalks, and drainage structures when connections are made.
2. 
Water service lines shall be a minimum of 1-inch Type “K” copper, and shall be provided with a corporation at the main and a curb stop located at least two (2) feet outside of curb with cover not to exceed 1-1/2 feet.
3. 
Sanitary sewer service lines shall be a minimum of 4-inch, shall meet the same requirements for sanitary sewers described above, shall be constructed from the main to the lot property line using ways and necessary bends, and shall have a minimum cover at the property line of four (4) feet, where possible.
4. 
Sewer services shall be located five (5) feet downstream from the center of each lot and as approved by the City Engineer.
5. 
Sewer services shall have a cleanout located at the property line and a 2' x 2' x 6" reinforced concrete pad which shall be poured around the cleanout. Provisions shall be made to connect the house sewer without disturbing the cleanout.
6. 
The subdivider shall make arrangements with all other appropriate utility companies for the extension of their respective utility lines and service to and within the addition and for any costs or refunds of such cost.
(Ordinance 88-14, sec. 6.19, adopted 7/26/88; Ordinance 98-11, sec. 1(D), adopted 2/10/98; Ordinance 2001-39, sec. 1(20), adopted 8/28/01)
1. 
Every application for a subdivision plat, an amendment to zoning regulations, or a development site plan relating to the development of property within the City shall be accompanied by a completed Trip Generation Threshold Analysis Worksheet substantially in the form set forth in Appendix E[1] to the Subdivision Regulations that has been prepared by a Professional Engineer licensed to practice in the State of Texas with experience in Transportation Engineering. The completed Trip Generation Threshold Analysis Worksheet shall be used to determine if, based on the number of proposed lots and the uses for which the property to be subdivided may be developed pursuant to applicable zoning regulations, the proposed development is expected to generate into and out of the property onto adjacent roadways:
a) 
500 or more vehicle trips per day; or
b) 
50 or more vehicle trips in the peak direction (i.e., inbound or outbound) during the peak traffic hour for the proposed development (typically a.m., p.m., or Saturday peak).
Trip generation rates shall be based on the most recent edition of the Institute of Transportation Engineers (ITE) Trip Generation Manual; provided, however, the City Engineer shall have the authority to authorize use of a different standard proposed by the applicant upon a determination that such other standard is more likely to be more accurate with respect to the vehicle trips that will be generated by the uses proposed to be developed on the property.
[1]
Editor’s note—Appendix E is included as an attachment to this chapter.
2. 
If the information provided on the Trip Generation Threshold Analysis Worksheet indicates the vehicle trips that will be generated by the proposed development and use of the property is anticipated to equal or exceed the levels identified in subsection 1, above, a Traffic Impact Analysis (TIA) that complies with the requirements of subsection 3, below, shall be prepared and submitted with the applicable development application. The City Engineer shall have the authority to require a TIA for developments that are not anticipated to equal or exceed the vehicle trip generation levels identified in subsection 1, above, but may impact a specific area or location, where there may be a known safety issue, or where there is likely to be change in the type of vehicles entering onto, exiting from, or traveling over the same roadways and/or through the same intersections, such as an increase in commercial vehicle or tractor-trailer vehicles entering onto, exiting from, and/or traveling on a roadway or traveling through an intersection which, prior to the development of the property, was primarily traversed by passenger vehicles traveling to and from residential developments within the area of such roadway or intersection.
3. 
Prior to commencing the preparation of a TIA, the applicant and the applicant’s representative who will be involved in the preparation of the TIA should meet with the City Engineer and/or other appropriate City Engineering Department staff in order to establish the requirements and scope related to the required TIA.
4. 
A TIA should include at least the following information:
a) 
Vicinity Map that includes the property that is the subject of the application and the study area of the TIA;
b) 
A Site Plan showing, as a minimum:
i. 
the proposed layout of the buildings, internal roadways, and parking areas to be constructed on the property to be developed; and
ii. 
all points of vehicle ingress and/or egress from the property onto adjacent roadways;
c) 
Existing Lane Use Assignments (inclusive of authorized travel direction and turning movements) and Traffic-Control Devices for all roadways and intersections within the required study area;
d) 
Existing Traffic Volumes (for each peak period) for all roadways and intersection within the required study area;
e) 
Projected Site Traffic Distribution Percentages based on full development of the property at the most intense permitted uses;
f) 
Projected Peak Hour Site Traffic Volumes (for each peak period) based on full development of the property at most intense permitted uses;
g) 
Horizon Year(s) Lane Use Assignments and Traffic-Control Devices;
h) 
Projected Horizon Year(s) Traffic Volumes (for each peak period) based on full development of the property at most intense permitted uses; and
i) 
Summary of Recommended Improvements, based on the changes in existing trip generations within the required study area resulting in the new trips generated by the proposed development necessary to:
i. 
prevent roadways and intersections within the study area with an existing Level of Service grade “C” or higher from dropping by more than one Level of Service; and
ii. 
prevent roadways and intersections within the study area with an existing Level of Service “D” or lower from dropping below the existing Level of Service.
5. 
The minimum study area for the TIA shall include all thoroughfares, intersections, freeway ramps, and driveways serving the development within approximately one (1) mile of the property. The City Engineer shall have the authority to require the study area of the TIA be extended beyond the one (1) mile boundary of the property to include critical locations which impact a specific area or location where there may be a known safety issue or where there is likely to be change in the type of vehicles entering onto, exiting from, or traveling over the same roadways and/or through the same intersections, such as an increase in commercial or tractor-trailer vehicles entering onto, exiting from, and/or traveling on a roadway or traveling through an intersection which, prior to the development of the property, was primarily traversed by passenger vehicles traveling to and from residential developments within the area of such roadway or intersection.
6. 
The TIA shall be prepared and sealed by a Professional Engineer licensed to practice in the State of Texas with experience in Transportation Engineering. The applicant shall submit three (3) copies of the TIA for review. In addition, an electronic copy, with all files used as part of the traffic analysis (i.e., Synchro, HCS, etc.) shall be provided with the TIA.
7. 
A TIA relating to the development of property located adjacent to roadway facilities controlled by and under the jurisdiction of the Texas Department of Transportation (TxDOT) shall also contain such information and otherwise be prepared in compliance with TxDOT guidelines. The applicant shall be responsible for coordinating and obtaining review and approval of the TIA by TxDOT when required by TxDOT.
(Ordinance 2022-33 adopted 6/28/22)