A. Increased stormwater runoff shall be minimized. Stormwater runoff from the subdivision shall be collected and conveyed by a drainage system approved by the City Engineer. The storm drainage system shall be designed by a registered civil engineer for ultimate development of the watershed and shall be capable of collecting and conveying runoff generated by a 10-year flood. The system shall provide for the protection of abutting and off-site properties that may be adversely affected by any increase in runoff attributed to the development; off-site storm drain improvements may be required to satisfy this requirement. In addition, retention ponds, drainage swales and/or check dams may be required to reduce off-site peak storm flow generated by projects to the historic flow.

B. Improvements shall be designed in accord with Sonoma County Water Agency criteria. Drainage improvements for runoff shall be engineered to minimize erosion through the use of rocked culvert inlets and outfalls, energy reducers, the location of culverts, etc. Design features shall include reseeding exposed slopes as well as minimizing the use of artificial slopes.

C. Fences along lot lines adjacent to proposed or existing surface drainage channels shall be designed in conformance with plans and designs approved by the City Engineer.

D. Curbs, gutters and cross gutters shall be designed in subdivisions to grades, cross-sections, layout and location as required and approved by the City Engineer.