Article II — Flood Control and Tract Drainage

Facilities for the control of tract drainage and floodwaters in Schedule "A," "B," "C," "D," "E," "F" and "G" land divisions are established as follows:

• A. The minimum design for facilities which control drainage water generated within a land division or floodwater flowing into or crossing a land division shall be based on a storm having a frequency of once in 100 years. Hydrologic and hydraulic calculations for the design of drainage facilities which control drainage water generated within a land division shall be submitted for approval to the Director of Transportation. Hydrologic and hydraulic calculations for the design of flood control facilities to control floodwater flowing into or crossing a land division shall be submitted for approval to the flood control agency having jurisdiction and to the Director of Transportation.

• B. The use of streets for flood control and drainage purposes may be prohibited by the Director of Transportation if the use thereof is not in the interest of the public health, safety and welfare.

• C. When the Director of Transportation permits the use of streets for flood control and drainage purposes, the 10-year frequency design discharge shall be contained between the tops of curbs or asphalt concrete dikes, and the 100-year frequency design discharge shall be contained within the street right-of-way. If either of these conditions is exceeded, additional flood control facilities shall be provided.

• (Ord. 18 § 2, 2008, RCC § 16.36.090)

• A. The flood control engineer shall review the hydrologic calculation submitted by the land divider and determine the adequacy of peak discharges of offside floodwaters impinging upon the land division from which protection must be provided. The land divider may consult with the flood control engineer or his/her representative as to the adequacy of the flood control facilities proposed.

• B. Improvement plans for flood control facilities to control floodwater flowing into or crossing a land division shall be approved by the appropriate flood control agency and the Director of Transportation.

• C. After receipt of an acceptable tentative map, the flood control engineer will recommend conditions to be imposed. He or she shall also furnish a flood hazard report to the land divider and such governmental agencies as may require the same.

• (Ord. 18 § 2, 2008, RCC § 16.36.100)

• A. Improvement plans for drainage facilities to control drainage water generated within a land division shall be approved by the Flood Control and Water Conservation District and Transportation Department.

• B. In land divisions where lot grading is not proposed, the following criteria are established:

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City of Wildomar, CA

WILDOMAR CODE

§ 16.32.110

§ 16.32.110

1. Where land division streets on sustained gradients cross natural drainage courses, adequate culverts shall be provided to accommodate the 100-year storm with maximum ponding to an elevation two feet below the road centerline profile grade, provided diversion of ponded water into another drainage area will not result therefrom.

2. Runoff in natural drainage courses exceeding the 100-year storm may be permitted to overtop the roadway in dip sections where, in the opinion of the Director of Transportation, topography, soil conditions, adjacent development and available allweather routes indicate its feasibility. If a deep section is permitted, the roadway embankment slopes shall be adequately protected.

3. Culverts of adequate size, but not less than 18 inches in diameter or equal, to prevent the 100-year storm from overtopping the roadway shall be provided in dip section or as approved by the Director of Transportation. Smaller culverts may be approved by the Director of Transportation.

4. Streets crossing improved channels shall be provided with culverts of adequate size to permit passage of the channel design flow or such other type of crossing as approved by the appropriate flood control agency and the Director of Transportation.

5. Asphalt concrete for lining of channels shall not be permitted.

6. When a land division substantially changes, concentrates or increases the natural flow of surface water onto adjacent property, facilities shall be required to direct the water to an adequate outlet, or the land divider shall obtain a recordable easement or written agreement for drainage purposes across the affected property.

• (Ord. 18 § 2, 2008, RCC § 16.36.110)

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City of Wildomar, CA § 16.36.010

SUBDIVISIONS