If circumstances prevented installing a bottom release pipe in your pond during construction, there’s another effective alternative. Add a siphon drain.
As outlined in previous newsletters, stagnant bottom water creates water quality issues. If you don’t have an aeration system, periodically discharging dead zones becomes more important. Fish can use greater areas of the water column. “Mucky” bottom layers will be reduced with higher oxygen content.
Common installations are constructed with four to six-inch plastic pipe for longer life. Intakes are placed at desired depths. Piping is run up the face of the dam, buried just under the surface across the top, and dropped off the back slope to a length just below the intake level. Accessories can be added to automatically initiate flow during high water events and stopped when water elevation returns to normal pool.
The key to successful siphons is AIRTIGHT seals and joints. They MUST be securely connected. If the slightest leakage occurs, air will seep into the system and interrupt flow.
Dam height and related engineering must be analyzed to determine if your pond is a candidate for a siphon. Appropriate governmental agencies must be consulted if your lake’s in a flood control program. Professional dirt contractors can assist with this evaluation. Now might be a good time to plan such a project while lake levels are low.