India has had good luck building solar panels over irrigation canals. The shade substantially reduces the evaporation losses in the canal system. The framing is a bit tricky of course.

This is actually fantastic news. I wonder if you're also utilising their secondary purpose (shading and improving microclimat https://www.sciencedirect.com/science/article/abs/pii/S00489...)

I learned about it on this episode of Volts

Fascinating consequences

https://www.volts.wtf/p/pakistans-solar-boom