Only get your money back if you sell or if the irrigation adds to the value of the crops I think.

On the sell side....are there any other properties in the area that you could comp this large impoundment to vs one that doesn't?

I don't know the area or the costs but if your annual crop value increases as a result of the irrigation....your ROI is paid over years.

If you were in the US I'd say you could also look at tax benefits based on improvements to the property. No idea how that works in your neighborhood though.

Might even be a program through the government available to help fund the project for water conservation.

Could always make the pond/lake on a smaller scale by using a canal from the raging river to feed it but not capture the raging river itself.

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