Article II — GENERAL CRITERIA AND STANDARDS

This chapter shall apply to any new residential, commercial, industrial, institutional or utility development.

(Ord. 508 §2.01, 1991).

The maximum allowable release rate of stormwater originating from the proposed development shall not exceed 0.15 cubic feet per second per acre and shall not exceed the predetermined safe carrying capacity of any limiting downstream restriction. If more than one detention basin is involved in the development of the area upstream of the limiting restriction, the allowable release rate from any one detention basin shall be in the direct ratio that its drainage area bears to the entire drainage area of the watershed.

(Ord. 508 §2.02, 1991).

The increased stormwater runoff resulting from the proposed development will be detained on-site by the provision of appropriate wet or dry bottom reservoirs, by leach trenches, by storage on flat roofs, parking lots, on streets, or by other acceptable techniques. Storage will be sufficient to store flows from twenty- five-year storms of four-hour durations in excess of the runoff from the site before development. Control devices shall limit the discharge from storage to a rate no greater than that prescribed by this chapter.

(Ord. 508 §2.03, 1991).

Measures which retard the rate of overland flow and the velocity in runoff channels such as swales or ponding are encouraged to par-tially control runoff rates.

(Ord. 508 §2.04, 1991).

Stormwater control systems may be planned in coordination by two or more property owners as long as flood or stormwater hazards are not increased at intervening locations.

(Ord. 508 §2.05, 1991).

A.

If detention storage is provided within a floodplain, only the net increase in storage volume above that which naturally existed on the floodplain shall be credited to the development. No credit will be granted for volumes below the elevation of the regulatory flood at that location unless compensatory storage is also provided.

B.

Facilities in Floodway Fringes. An exception to the policy in subsection A of this section is authorized when the floodways and floodway fringes have been established for floodplains by state or federal agencies. Under those conditions, detention facilities may be authorized in floodway fringe areas and no compensatory storage will be deemed necessary.

(Ord. 508 §2.06, 1991).

The total tributary area must be used in calculating the allowable release rate. The required storage volume will be based on the project area only, with extraneous flows from upland areas being bypassed or discharged via overflow spillways or other devices.

(Ord. 508 §2.07, 1991).

All computations, plans and specifications related to the implementation of this chapter must be prepared and sealed by a pro-fessional engineer registered in California.

(Ord. 508§2.08, 1991).