Contra Costa County Municipal Code Ch. 914-10 Levees

Adequate levees shall be provided in compliance with Section 914-2.002.

(Ords. 89-28, 78-5).

All levees in excess of three feet in height shall be designed by a licensed soil engineer and shall require the submittal of a soil report.

(Ord. 89-28).

For levees used in combination with open channels and waterways, the toe of the levee on the water side shall be placed at least two feet back from the top of the bank of channel or waterway. Levee side slopes shall not be steeper than two horizontal to one vertical.

(Ords. 89-28, 78-5).

Top width of levees constructed for the protection of reclaimed lands or the containment of open channels shall not be less than eighteen feet.

(Ords. 89-28, 78-5).

Top width of levees constructed for protection of any portion of the subdivision from surface waters shall not be less than five feet.

(Ords. 89-28. 78-5).

The degree of protection for which levees shall be designated shall be as follows:

(1) For watercourses and channels, levees shall provide the degree of protection as specified in Section 914-2.002 and shall include no less than three feet of freeboard;

(2) For those areas to be protected from waters of San Francisco Bay and San Pablo Bay from the southerly and westerly boundaries of Contra Costa County to the state highway bridge at Carquinez Strait, levees shall provide protection from tides and from waves created by wind action. Tops of curbs shall be not lower than elevation 7.5 U.S.G.S. datum;

(3) For those areas to be protected from the waters of Carquinez Strait and Suisun Bay from the state highway bridge at Carquinez Strait to Simmons Point on Chipps Island, levees shall provide protection from tides, flood flows in the Sacramento and San Joaquin Rivers, and waves created by wind action. The basis for flood protection shall be the U.S. Army Corps of Engineers' standard project flood, approximately equivalent to a recurrence interval of two hundred years. Tops of curbs shall be not lower than elevation 8.5 U.S.G.S. datum;

(4) For those areas within the delta area from Simmons Point on Chipps Island to the easterly boundaries of Contra Costa County, levees shall proviAe protection from tides, flood flows in the Sacramento and San Joaquin Rivers and all waterways tributary thereto, and waves created by wind action. The basis for flood protection shall be the U.S. Army Corps of Engineers' standard project flood, approximately equivalent to a recurrence interval of two hundred years. Tops of curbs shall not be lower than elevation 9.5 U.S.G.S. datum.

(Ords. 89-28, 78-5).

Approval of the design and construction of all levees within those areas described in Section 914-10.012 (2), (3) and (4), shall be obtained from the U.S. Army Corps of Engineers, California State Reclamation Board. San Francisco Bay Conservation and Development Commission, and any active operating local reclamation district within whose boundaries levees are to be constructed.

(Ords. 89-28, 78-5).

The jurisdiction for the control and maintenance of all required levees shall be determined by the county, except as to areas where reclamation districts or districts with similar powers have such responsibilities, in which case the district having that responsibility shall present assurances satisfactory to the county that it has the necessary means and will perform the continued necessary maintenance of those levees protecting the subdivision.

(Ords. 89-28, 78-5).