Sumps and Ejectors.
§ 18-29-712.1 Building drains below sewer.
Building drains that cannot be discharged to the sewer by gravity flow shall be discharged into a tightly covered and vented sump, from which stack the liquid shall be lifted and discharged into the building gravity drainage system by automatic pumping equipment or other approved method.
§ 18-29-712.2 Check and gate valve required.
A gate valve located on the discharge side of the check valve shall be installed in the pump or ejector discharge piping between the pump or ejector and the gravity drainage system. Access shall be provided to such valves. Such valves shall be located above the sump cover required by Section § 18-29-712.1 or, when the discharge pipe from the ejector is below grade, the valves shall be accessibly located outside the sump below grade in an access pit with a removable access cover.
Exception: In single family residential buildings, only a check valve shall be required, located on the discharge piping from the sewage pump or ejector.
§ 18-29-712.3 Sump design.
§ 18-29-712.3.1 Sump pump.
The sump pump capacity and head shall be appropriate to anticipated use requirements.
§ 18-29-712.3.2 Sump pit.
The sump pit shall be not less than 18 inches (457 mm) in diameter and 30 inches (762 mm) deep, unless otherwise approved. The pit shall be accessible and located such that all drainage flows into the pit by gravity. An approved sump pit or tank within a building receiving the discharge from sanitary drains, storm water or combined drains shall be constructed of steel, cast iron, reinforced concrete pipe or other approved materials. The sump or tank receiving the discharge from subsurface soil drainage shall be constructed of vitrified clay tile or any of the above materials. Approved plastic or fiberglass liners may be used in conjunction with any of the approved materials referenced above. The pit bottom shall be solid and provide permanent support for the pump. The sump pit shall be fitted with a gas-tight removable cover adequate to support anticipated loads in the area of use. The sump pit receiving sanitary flow shall be vented in accordance with Article § 18-29-9.
(Amend Coun. J. 3-27-02, p. 82090, 3)
§ 18-29-712.3.3 Discharge piping.
Discharge piping shall meet the requirements of Section § 18-29-712.2.
§ 18-29-712.3.4 Maximum effluent level.
The effluent level control shall be adjusted and maintained to at all times prevent the effluent in the sump from rising to within 2 inches (50 mm) of the invert of the gravity drain inlet into the sump.
§ 18-29-712.3.5 Ejector connection to the drainage system.
Pumps connected to the drainage system shall connect to the building sewer or shall connect to a wye fitting in the building drain a minimum of 10 feet (3.05 mm) from the base of any soil stack, waste stack or fixture drain. Where the discharge line connects into horizontal drainage piping, the connector shall be made through a wye fitting into the top of the drainage piping.
§ 18-29-712.4 Sewage pumps and sewage ejectors.
A sewage pump or sewage ejector shall automatically discharge the contents of the sump to the building drainage system.
§ 18-29-712.4.1 Capacity.
A sewage pump or sewage ejector shall have the capacity and head for the application requirements. Pumps or ejectors that receive the discharge of water closets shall be capable of handling spherical solids with a diameter of up to and including 2 inches (50 mm). Other pumps or ejectors shall be capable of handling spherical solids with a diameter of up to and including 1 inch (25 mm). The minimum capacity of a pump or ejector based on the diameter of the discharge pipe shall be in accordance with Table § 18-29-712.4.1
Exception: Grinder pumps or grinder ejectors that receive the discharge of water closets shall have a minimum discharge opening of 1 1/4 inches (32 mm).
§ 18-29-712.4.2 Duplex equipment required.
Where six or more water closets are connected to a sewage ejector, the system shall incorporate duplex pumping equipment.