CPP SMOOTH CORE / n-10
FLASHBOARD RISERS
For pond and wetland water level control

Flashboard Riser water level control structures, with their Increase-Decrease style of incremental movable boards, have been used for centuries to control water levels in ponds, polders and marshes. The movable board or log system has been installed in log headwall channel rails, concrete channel rails, fabricated metal pipes and now fabricated CPP Smooth Core/n-10 pipes. CPP Smooth Core/n-10 Flashboard Risers are ideal for adjusting the water level of small ponds or water containment basins. They are fabricated from HDPE (High Density Polyethylene) plastic which will not rust. Durable HDPE plastic is also more resistant to sediment abrasion then other raw materials.

INSTALLATION GUIDELINES

CPP Smooth Core/n-10 durable plastic Flashboard Risers are lightweight, and easy to transport to isolated pond locations. Because water soaked, movable muck soils will be surrounding any flashboard riser system, the riser must be anchored in an unmovable concrete pour to prevent headwall washout. A minimum twelve-inch concrete foundation is recommended under the invert of the outlet stub, and around the half circle headwall-footing base. The plastic headwall riser’s corrugated exterior walls will provide a positive interlock for the concrete pour. Additional concrete maybe needed at the headwall wings depending on the quality of native site materials used to backfill around the plastic flashboard riser structure. Concrete should also be poured at the stub-out connection joint to secure a watertight joint for the outlet drainpipe. A plywood horseshoe saddle or a partial backfill over the outlet pipe beyond the coupling stub joint will provide a concrete form. A CPP MASTIC based watertight coupler should be applied to the joint prior to the pour of concrete.

CONCRETE FOUNDATION FLANGE	OUTLET STUB CONNECTIONS
A Twelve-Inch extension is provided below the bottom of the outlet stub pipe for securing this structure into a concrete foundation footing.	A view of the exit side stub-out for receiving CPP Smooth Core/n-10 high volume flow outlet pipe. Connections here should be made with CPP MASTIC watertight couplers, and concrete encased to prevent muck soil movement.