(A) Sewage facilities, if required. Sewage systems shall in all respects conform with the city’s Comprehensive Plan and meet the requirements, in all respects, TCEQ and Collin County. The city shall make the final determination of the adequacy of facilities proposed. The systems shall be designed according to the city standards, as established by the City Engineer, with approval by the Council. The developer shall install all sewage facilities at the developer’s cost.
(1) Necessity and adequacy. Sanitary sewer facilities, if required by the city, county, or state, shall be furnished and installed to adequately service the subdivision. The necessity or adequacy of the sewerage facilities provided by the developer shall be determined by the city.
(2) Minimum size main. The minimum diameter of sewer mains shall be 8 inches. Six-inch diameter sewer mains may be acceptable only for short distances, not to exceed 400 feet, and only in locations approved by the city. Peaking factors shall be determined by the City Engineer.
(3) Location. Sewer lines shall be located in street rights-of-way or in easements (minimum width 15 feet), and shall be a minimum of 6 feet deep to the invert, unless a shallow depth is approved by the City Engineer. Easements shall be provided for sewer lines that parallel state numbered highways.
(4) Alignment and grades. All sewers shall conform to the requirements of TCEQ.
(5) Lift stations. All lift stations shall be designed and constructed with 2 or more sewage pumps, and the stations shall be capable of pumping the design maximum flow with the largest pump out of service. Detailed design data, plans, and specifications of the pumps shall be submitted to the City Engineer with the final plat. The City Engineer shall designate the peaking factor. Lift station design shall meet the requirements of TCEQ.
(6) Force mains. At design for maximum flows, a cleansing velocity of at least 2 feet per second shall be maintained. Where necessary, automatic air release/vacuum valves shall be placed at high points in the force main to prevent air locking. Air valves shall be kept to a minimum as determined by City Engineer. Reasonable pressures in the force main shall be a maximum of 20 psi, unless higher pressure is accepted by the City Engineer and approved by the city.
(7) Meter station. When meter stations are necessary, the plans for the station shall be submitted to the city and the treatment authority for review with the construction plans for the subdivision.
(8) Cleanouts. Standard cleanouts shall be constructed at the ends of all sanitary sewers where no future extensions are planned. Two-way cleanouts shall be installed and located at or near the property line of each lot connected to the sanitary sewer. Other cleanouts may be required at other locations as determined by the City Engineer.
(B) On-site wastewater systems. On-site systems shall be designed and constructed according to TCEQ Construction Standards for On-Site Wastewater Facilities, and the requirements of Collin County and the city for on-site wastewater systems. The final construction plans shall contain data and typical design of the system for on-site disposal of wastewater. The city requires a residential lot of 1 acre minimum area per residential unit for the installation and use of an on-site (septic) wastewater system.
(Ord. 487, passed 7-18-2000; Am. Ord. 737, passed 7-20-2016) Penalty, see § 155.999