Old house, leaking concrete cistern

[jbclem]

My 100 year old house has two concrete cisterns for rainwater collection. One holds water, but the other one, a 14 ft deep x 5 ft diameter cylinder, leaks and won't hold more than a foot of water. I'd like to ask for suggesions on sealing the leak(s). Is there a particular type of concrete patch that I should use, and is there a sealer that should be applied on the inside walls? Any ideas would be helpful.

John

 

[Valveman]

Never had much luck patching concrete tanks. Will the top come off? You might just drop a new poly tank inside the concrete one?

 

[BlueSkyHigh]

I know this may come across as funny, but what about getting a mess of that as-seen-on-TV "Flex Seal" stuff or equivalent?

 

[wpns]

You might try some of those paint-on waterproofing paints, but when my new cistern wouldn't stop leaking they finally coated it inside with pool cement, and it's been fine for 15 years. Finishing the bottom can be tricky, but the walls were easy.