Hi everyone,
I�m in the early stages of managing a 50-year old, 4-acre pond in Oklahoma, and the lack of rain over the past couple of years has gotten me more interested in increasing the �normal� water level. The primary goal is to increase the odds that during such extended drought conditions, we�re retaining enough water to sustain the fish population. The secondary goal is to make it deeper just because that�s what I want.
I�m contemplating the best way(s) to accomplish this; your ideas and opinions would be appreciated!
We all like pictures, so I will take a shot at including some photos and providing some background to set the scene�
This pond is the result of a pretty good-sized dam (33� elevation, 50,000 cu. yd. soil) that was constructed jointly by local authorities and federal Soil Conservation Service as a flood prevention project in 1966.
The surface area is approximately 4 acres, average depth perhaps 4 feet, max depth 11 feet and plenty of 2 feet depth at the upper end of the pond where much sediment has wandered in over the years. (There are also two other secondary inlets that have carried a lot of sediment in; all noted in photos below.)
The photo above shows the pond at approximately 3� below �normal� water level. Also illustrated by arrows are points where substantial amounts of sediment have accumulated creating much shallower areas; and one arrow highlighting the large distance between primary spillway and top of dam. Additionally, you can see the length and height of the dam itself.
In the photo below, the slopes at these two locations are vastly different� just can�t see it very clearly here.
The original SCS design of the dam and primary spillway specified 19 feet of freeboard; as built, I believe the actual distance is 17 feet.
Recently the original spillway riser and drain valve were replaced, having rusted out. The metal riser was replaced with heavy walled polyethylene pipe, along with a new gate valve and corrugated steel crown. (See photos.)
The new riser is positioned at same elevation as previous one, with 17 feet of freeboard.
And as you can almost see in the pic below, the drought last year has caused water level to recede well below the drain valve (still have 5 feet of water depth in some areas; 12 inches in others).
I believe the pond basin is basically a smooth bathtub shape, and the opportunity to completely empty the reservoir and re-work the bottom would be enjoyable. But between cost of doing so and the current good quality of fishing, pumping out the whole thing is not currently on the radar.
So� if a person wanted to increase water depth in this pond, how would you recommend that be accomplished?
Look forward to hearing some great ideas! Thanks, in advance, for your input.
