Section 124 - Abandoned Pipelines and Conduits(a) Abandoned pipelines, conduits, and all appurtenances (such as pumps, standpipes, or positive closure structures) that are located within a levee section, within the projected levee section, or within ten (10) feet of the levee toes shall be completely removed, when practical, and disposed of outside the floodway. (1) When the invert of an abandoned pipeline or conduit within a levee is above the design flood plane elevation, the pipeline or conduit must be removed.(2) An abandoned pipeline or conduit located within one (1) foot of the surface of the levee slope shall be removed.(3) When the invert of an abandoned pipeline or conduit within a levee is six (6) feet or less below the design flood plane elevation, the board may require the removal of the pipeline or conduit.(4) The side slopes of an excavation to remove an abandoned pipeline or conduit from within a levee must be one (1) foot horizontal to one (1) foot vertical or flatter.(5) After any pipeline, conduit, or appurtenance is removed from a levee, approved backfill shall be keyed into the levee section with each lift and compacted in four- (4) to six- (6) inch layers with a relative compaction of not less than ninety (90) percent, per ASTM D1557-91, dated 1991, which is incorporated by reference and above optimum moisture content.(6) Compaction tests by a certified soils laboratory will be required to verify compaction of backfill within a levee or within the projected levee section.(b) Abandonment of pipelines and conduits within a floodway must be in a manner consistent with the following: (1) After any pipeline, conduit or appurtenance is removed from a floodway, open-trench backfill must be placed in a manner consistent with the local conditions. Erosive stream reaches will require methods that compact the backfill to at least the density of that of adjacent soils. Compaction tests by a certified soils laboratory may be required to verify compaction within the floodway.(2) Abandoned pipelines or conduits within the berm and within thirty (30) feet of the top of the streambank must not be filled with concrete but may be removed if exposed by bank erosion.(c) If it is determined by the board that it is impractical or detrimental to the levee to remove an abandoned pipeline or conduit from a levee section, the pipeline or conduit must be completely filled with concrete. (1) Concrete to be used to fill an abandoned pipeline or conduit must be a three- (3) sack cement mix, or equivalent, with aggregate having a maximum size of three-eighths ( 3/8) inch, and a water content sufficient to produce a six- (6) to eight- (8) inch slump.(2) A detailed plan for filling an abandoned pipeline or conduit with concrete may be required to be submitted for approval by the board prior to start of work.(3) A pipeline or conduit to be filled with concrete must have a minimum cover of three (3) feet below the waterward levee slope.(4) See Figure 8.07 for illustrated details on sealing abandoned pipelines and conduits.(d) Concrete pipes may be plugged with concrete at each end as an alternative to complete filling. The length of each plug shall be a minimum of two (2) feet or twice the diameter of the pipe, whichever is greater.Cal. Code Regs. Tit. 23, § 124
1. New section and figure 8.07 filed 9-30-96; operative 10-30-96 (Register 96, No. 40). Note: Authority cited: Section 8571, Water Code. Reference: Sections 8608 and 8710, Water Code.
1. New section and figure 8.07 filed 9-30-96; operative 10-30-96 (Register 96, No. 40).