I have a 20 acre pond in Eastern Virginia that we have to do some spillway improvements on soon. In order to do so we have to lower the water level 4', max depth is 9.5' and the average depth is probably 7-8'. We are supposed to start the drawdown middle of next month, May 15th and we will need to have it at that level for approximately one month. Everything i have read discourages summer drawdowns for obvious reasons. How concerned should I be about the fishery and is their anything i can do to make it less stressful for the fish. There is no power at the location. Any help or advice would be greatley appreciated.
Fish the snot out of the pond and take out 100's and 100's of pounds of fish. Even without power there, air can be run a long, long ways underground from electricity where the compressor is located to the pond, then spread out into the pond. If that is not an option, then since you are removing over 50% of the volume of water in the pond, you really should remove about 50% of the fish population by weight. The quickest way to do that is to get an electroshock boat in there once the pond is drawn down and take out every fish that doesn't meet your management plan plus more. With the renovation and draw down, the fish population will rebound back VERY quickly.
Waiting until it's drawn down makes pretty much the whole fish population accessible to the shock boat and it is a perfect time to have that done. 20 acres, plan on a whole day going around the pond a few times. Have a fishery plan in place so you aren't wasting time that day deciding what to take out and what to leave. I'd plan on taking out a LOT of fish due to the pond size. Contact some church groups, food pantries, hunters feeding the hungry, Boy Scouts, Girl Scouts and other organizations that could use the fish or help clean the fish so that they can go to organizations that could use the fish. Make the organizations aware that the fish will NOT be cleaned and ready to put in the fridge or freezer right from the pond.
If it's an older pond, that draw down would be the perfect time to add fish habitat to the shallow areas too.