You could have a look at ...

You could have a look at Spain's water governance system. Their water user's associations are decentralized and relatively small (I visited one of 1900 hectares), managed by the local communities. Every member has the right to vote for the WUA's decisions. They receive subsidies by the regional and national government, but make u the laws themselves. The small-scale and bottom-up nature of this governance makes that I think this could be an option for local water management and governance in developing countries.