Sec. 4-188. Soils and Foundations; Section 1805, Dampproofing and Waterproofing

Section 1805.4.3.1 is added to read as follows: "Foundation Drainage." In no case shall a discharge pipe of foundation drainage be connected to a public sanitary sewer or a septic system.

Section 1805.4.3.4, Sump Pumps and Pits. Where subsoil drains do not discharge by gravity, the drains shall discharge to an accessible sump pit with an automatic electric pump. A battery back-up or water-powered back-up sump pump will also be provided. Sump pit shall be a minimum of twenty-four (24) inches in diameter, or eighteen (18) inches square and twenty-four (24) inches in depth and be provided with a fitted cover. The sump pump shall have adequate capacity to discharge all water coming into the sump as it accumulates, but in no case shall the capacity of the pump be less than fifteen (15) gallons per minute. The discharge from the pump shall be a minimum of one and one-fourth (1¼) inches and shall have a union in the discharge piping to make the pump accessible for servicing. Subsoil drains and sump pump discharge may discharge to a properly graded open area provided the point of discharge is ten (10) feet from any property line or Building Restriction Line (BRL). Where a continuously flowing spring or high groundwater table is encountered during the design stage, basement floors shall be designed at least two and one-half (2.5) feet above the groundwater's highest detected level. Alternatively, pre-approved methods of permanent dewatering shall be provided, and groundwater level shall be verified again before construction. If such condition is encountered after construction, and subsoil drains are pre-approved by the County, these drains must be piped to a storm drain or approved outfall where they shall be fitted with an accessible backwater valve. Residential sump pumps are not to be relied on for lowering high groundwater table.

Section 1805.4.3.5, Areaway Drains. All open subsurface space adjacent to a building serving as an exit or entrance shall be provided with a drain or drains. Such areaway drains shall be of approved material in accordance with the International Plumbing Code (IPC) and not less than two (2) inches in diameter and shall discharge by gravity or mechanical means. Areaway drains for areas exceeding 100 square feet shall be sized in accordance with Section 1114 of the 2015 IPC and be a pre-approved design.

Section 1805.4.3.6, Window Well Drains. Window well areaways shall have drains. Window well areaways ten (10) square feet or less may discharge to the subsoil drain through a two-inch minimum diameter pipe.

Section 1805.4.3.7, Foundation Weep Holes. Where subsoil drains are required by Section 1805.4.2, foundations of hollow core masonry shall have foundation weep holes. Weep holes shall be placed a maximum of 4-foot o/c intervals and shall discharge into the aggregate of interior subsoil drainage system.

Section 1805.4.3.8, Site Grading. The ground immediately adjacent to the foundation shall be sloped away from the building at a slope of not less than one unit vertical in twelve (12) units horizontal (1:12) for a minimum distance of 5 feet (914 mm) measured perpendicular to the face of the wall or an approved alternate method of diverting water away from the foundation shall be used. Consideration shall be given to the possible additional settlement of the backfill when establishing the final ground level adjacent to the foundation.