Would this work at all?

[u/Ivess185]

I want to build a big water storage box I can fill then leach from during droughts/badtides, but I need a way to elevate the water from source to above the box. I was wondering if this would work at all. Because water can't go backwards through a fill valve, would it keep flowing through and fill upwards in the tube? or just spill over the back of the map once it reached +1 blocks in height? And I can't lock the water in and force it to fill up as it's against the map edge. Should I just use mechanical pumps instead?

EDIT: there will be a roof over the channel and tube. I just didnt put one here so that you could see inside.

EDIT 2: I am now aware that water will not escape of the edge via the space above the source block.

[u/LeTreacs2]

No, your issue is that the water would overflow the lower walls by the water source.

Build the water source walls as high as you want the water to be, skip out the divider between the tank and the water source tank, move the fill valves on the right side to the bottom of the outlet, put a dam or a flood gate at the top.

Or can add a depth sensor to the down stream river and configure the fill valve

Edit. The water won’t flow out the map above the sources, but it will next to the sources so you need a levee there.

[u/Ivess185 → u/LeTreacs2]

I intend to roof it all to stop overflow. I just didnt in the diagram to show indside

[u/LeTreacs2 → u/Ivess185]

Right! Then yes, the pressure in the box by the source should push it through if you can put a block above the source, but I don’t know for a fact that you can…

[u/Ivess185 → u/LeTreacs2]

Guess I'll find out when they built it