What could possibly get pumped from the sump? Normally perhaps just seepage due to rain (in our house it would be water softener recharge water, if we had a sump pump), but in case of accidents - clothes/dishwasher water, broken sewage line??? I doubt the volume of water gained is worth the risk.

I have (barn) downspout lines which head towards the pond, but dump above ground and filter through grass before reaching it so I am not worried about bird poop or anything else that might be on the roof when it rains.

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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