Hydro Plant not allowing water flow through

In my city, I have a hydro plant that is sitting across a river quite near my city. This dam holds back all of the water and there is a significant drop in water level before and after. When I say significant difference, I mean that on the up-river side the river is lapping at the edges of the river and at the down-river side, the river is totally empty.
However, my problem is that the hydro plant doesn't let any water through, and therefore is not generating any power (0MWh out). I can't for the life of me work out why this is happening, and it's bugging me because I don't want to have to buy another solar plant just yet.
The river in question runs out of a lake, joins with another river and then runs out into the sea. Although I do have water pumps on the upriver side of the dam, they are not consuming anywhere near enough water to totally drain the river.
Are there any ideas as to why I can't get my free river power?
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Why is hydro power plant not working cities skylines?
to get the dam to work, you just need the water to fill all the way to the top. then it should work. if you are flooding areas then probably the water level is never getting high enough. never raise the dam too high for the highest potential water level the water can reach if a dam were there.Why is my dam not working cities skylines?
If your dam keeps turning on and off, then your dam is not getting enough of the water it needs. Either lower the dam's height, find a more suitable location or relocate your city's drains to the high side of the dam.How do you increase water flow in cities skylines?
Canals and quays may be used to direct water flow, as well as the landscaping terraforming tools. Mayors need to provide their city with water and sewage services. Most cities will extract water using shoreline water pumping stations to provide water for the citizens.How does the hydro power plant work cities skylines?
The hydro power plant is a power-generating structure capable of generating between zero to 1,600 megawatts. The hydro power plant must be built over a river with each end point connecting to some form of land. It is unlocked by meeting the Small City milestone.What Happens When a Reservoir Goes Dry?
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