SECTION P-1101  GENERAL
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P-1101.2 Disposal.All rainwater from roofs and storm water from paved areas, yards, courts and courtyards shall drain to an approved place of disposal. For one- and two-family dwellings, and where approved, storm water is permitted to discharge onto flat pervious areas, such as streets or lawns, or area drains provided that the storm water flows away from the building.
P-1101.2.1 Area drain. Area drains shall be provided on all premises in the locations required by items 1 through 6 below:
1.   Paved areas, courts, open shafts in excess of 5000 square feet.
2.   Driveways of any area which slope downward toward the building.
3.   Terrain which slopes downward toward the building within 10 feet of the building's exterior walls.
4.   Terrain which creates a low elevation such that standing water is possible.
5.   Terrain which slopes downward toward adjacent property in such a manner as to concentrate the flow of runoff.
Exception: Where terrain slopes toward a natural watercourse such as a creek, stream or river, an area drain shall not be required.
6.   At the low point of any swales on the property.
Exception: Where terrain slopes toward a natural watercourse such as a creek, stream or river, an area drain shall not be required.
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P-1101.9Backwater valves. Storm drainage systems shall be provided with backwater valves as required for sanitary drainage systems in accordance with Section 714.
Exception: Storm drainage systems and private on-site stormwater management systems located outside the 100-year floodplain or connected to the public storm sewer.