Section 281.836. Trench excavation.

(1) All pipe trenches shall be excavated to a depth which will provide a minimum cover of 30 inches from the bed of the stream to the top of the pipe. This minimum cover shall  control   except  where  special conditions at certain water crossings may warrant a  lesser  or  greater depth of cover.

(2)    Appropriate trench excavation methods shall be employed to minimize material from the  pipe  trench   flowing  into   the  stream,  giving  due consideration to the soil, terrain, cover, side  slopes  and  weather conditions involved.

(3)   The pipe trench excavation shall stop some distance from the stream to leave a protective plug of 10 to 20 feet of  unexcavated  material  at  each bank. The  plugs shall be left in place until the pipe-laying operation across the stream has begun. Bypassing of water in the trench to the side by diversion ditches or by pumping may be required  at  certain water crossings.

(4)   The trench in the stream bed may be backfilled if the material used does not cause excessive siltation. Stone, coarse  aggregate  or  washed gravel shall be used where backfill is required and where use of existing material will cause excessive siltation.

(5)   Pumping or draining from trench excavations shall be made on either side of the pipeline and not into the waters of the state. The owner shall secure the necessary approval of private landowners before  discharging water from the trench excavation onto private lands.

History: 1979 AC.