While i figured evaporation was going to add up , and being on city water. I opted to build a 3000 gallon cistern . Now anyone new to ponding or just in the planning stages would think thats an insane amount of water you'll never use that. When in actuality i wish i had gone even bigger so i didn't have to monitor the evaporation rate ever. I collect half the rain from my roof, it runs down the gutters and into the pond. as the pond over flows this drops into the cistern.
Now the cost when i was building it was the biggest concern. as 80 large aqua blocks and a liner that was 35 x35 is not cheap.
As usual in building budgeting up to 35% more than your estimate is always a good idea. As i did go over the original costs as when i was digging what did i come across? but the old 1920's construction trash dump in building the house.
they use to dig a hole and throw all the left over cuts of lumber , tin cans left over roofing, ceramic tile and yes the whiskey bottles. Now i could have opted for a thick layer of sand but i know mother nature all too well and know in a cold climate she can push a boulder a foot a year underground , so some broken shards of glass or nails were all too easy to push into the liner and puncture it. my solution was to line the entire pit with 3/4", azek or "pvc " sheathing.
Long story short it was costly but it is now a one time expense and my water level in the pond ALWAYS is a constant only the cistern fluctuates you never seen the liner or water drop. But if memory serves me it did run over 4,500 dollars in materials alone, and that was before Bidennomics. So today i'd bet 6500 would be in the right neighborhood
Ok just did a quick look up 5600 for aquablocks 1500 for liner and 350 for a small pump and 300 bucks for 2 inch flex grand total over $7500 bucks sorry my financial estimate was a bit poor is used the official costs are up only 20% when in actuality its closer to 40% so bring on the free rain water.
so 5 years ago when the cistern went in the price was a bit hard to chew, today i am more than grateful for pulling the trigger.