Without buttressing and making a bow shape, a 10ft tall block wall can be blown over by a strong wind, let alone water. The rebar would just assure it would all fall over together. I am thinking there would be a lot more to it than a simple line of block with rebar to hold back water.
I would imagine it being cheaper and easier to dozer up a proper dam/berm, then line the basin with impermeable material. It would probably look better too.
I agree. The block wall will tip over rather quickly. no matter how much reinforcement you put inside it. Look at all the dams that are built to retain water. NONE are made from block, NONE are built in a straight line.If you want to build a block wall, reinforce it with rebar and concrete, that's ok, but to get it to hold and not fall over with the water pressure you will have to backfill behind the block wall, and properly compact the soil while backfilling, which means getting moisture in it and compacting with a sheepsfoot roller. I would carry the soil out 30 feet behind the top of the10' block wall.
For the RPE liner, remember that you have to cover it with dirt to protect it from the UV rays. I am seeing lifespans of 3-10 years exposed and 20 years (or more) when they are covered with dirt and protected from the UV rays. In your location, I would suspect that exposed time to be even shorter than that.
It might just be cheaper to make the whole thing from dirt, THEN install the liner and cover the liner.
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