Hey David, it almost sounds like the damming of the outflow has done you a favour... 5 foot deep water throughout is a possible recipe for a weed choked lake, especially with the level of sediment inflow you describe. It would likely be much worse then it is now without your added depth. Is the wooded area flooded significantly... re. more then 1 foot of water?

Are there any obvious flows of water into the lake that you could create sediment ponds in to trap out some before it gets to the main water body?

A good place to start with species control is to catch out as many Green sunfish and Bullheads you can. (You may need to resort to trapping out the bullheads if they are present in significant numbers).

From a structural standpoint, do you see any weak areas on the damn that could be a problem with the extra depth or in the event of a major inflow activity? (Sounds like the properly sized emergency spillway is in place and should be able to handle excess emergency flow... the fact that it is still 3 feet higher then current depth leads me to believe the damn was created with the intent of being able to store at least as much water as you currently have, without issue.) How much continuous in or outflow do you have? How much of the current outflow system would you say is used? (i.e. could;d even a small amount of extra inflow cause another rise in water height) Can the existing outflow be further impaired by beavers?

Lots of things to think about...

Owner/Builder of Ottawa Canada's first official off-grid home.

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