If you mean the two fold purpose of a hydroelectric dam as a water reservoir and power source, yeah. But, IRL, water is less dependable than in C:S so reservoirs make sense for the purpose of storing water. In C:S, water always flows, there is no rainfall mechanic nor drought mechanic. Groundwater doesn't exist, and we can't build canals (the most common way of utilizing water from reservoirs, AFAIK).