1503.7 Drawings and Specifications. The Authority

Having Jurisdiction may require the following information to be included with or in the plot plan before a permit is issued for a gray water system, or at a time during the construction thereof: (1) Plot plan drawn to scale and completely dimensioned,

showing lot lines and structures, direction and approximate slope of surface, location of present or proposed retaining walls, drainage channels, water supply lines, wells, paved areas and structures on the plot, number of bedrooms and plumbing fixtures in each structure, location of private sewage disposal system and expansion

area or building sewer connecting to the public sewer, and location of the proposed gray water system. (2) Details of construction necessary to ensure compliance

with the requirements of this chapter, together with a full description of the complete installation, including installation methods, construction, and materials in accordance with the Authority Having Jurisdiction. (3) Details for holding tanks shall include dimensions, struc tural calculations, bracings, and such other pertinent data as required. (4) A log of soil formations and groundwater level as deter mined by test holes dug in proximity to proposed irrigation and/or disposal area, together with a statement of water absorption characteristics of the soil at the proposed site as determined by approved percolation tests. Exception s : (1) The Authority Having Jurisdiction shall permit the

use of Table 1504.2 instead of percolation tests. (2) The Enforcing Agency may waive the requirement

for identification of groundwater level and/or soil absorption qualities based on knowledge of local conditions. (3) The absence of groundwater in a test hole three (3)

vertical feet (915 mm) below the deepest irrigation or disposal point shall be sufficient to satisfy this

TABLE 1503.4 LOCATION OF GRAY WATER SYSTEM ⁷

For SI units: 1 foot = 304.8 mm Notes: 1 Building structures do not include porches and steps, whether covered or uncovered, breezeways, roofed carports, roofed porte cocheres, roofed patios, carports, covered walks, covered driveways, and similar structures or appurtenances. 2 The distance shall be permitted to be reduced to 0 feet for aboveground tanks where first approved by the Authority Having Jurisdiction. 3 Underground tanks shall not be located within a 45 degree angle from the bottom of the foundation, or they shall be designed to address the surcharge imposed by the structure. The distance may be reduced to six (6) inches (153 mm) for aboveground tanks when first approved by the Enforcing Agency. 4 Where special hazards are involved, the distance required shall be increased as directed by the Authority Having Jurisdiction. 5 These minimum clear horizontal distances shall apply between the irrigation or disposal field and the ocean mean higher high tide line. 6 Add 2 feet (610 mm) for each additional foot of depth more than 1 foot (305 mm) below the bottom of the drain line. 7 For parallel construction or crossings, approval by the Authority Having Jurisdiction shall be required. 8 The distance shall be permitted to be reduced to 11 ⁄ 2 feet (457 mm) for drip and mulch basin irrigation systems. 9 The distance shall be permitted to be reduced to 0 feet for surge tanks of 75 gallons (284 L) or less. 10 The minimum horizontal distance may be reduced to 50 feet (15 240 mm) for irrigation or disposal fields utilizing gray water which has been filtered prior to entering the distribution piping.

308 2022 CALIFORNIA PLUMBING CODE

section unless seasonal high groundwater levels have been documented to rise to within this area. (5) Distance between the plot and surface waters such as

lakes, ponds, rivers or streams, and the slope of the plot and the surface water, wherein close proximity.