How To Find Leak

[fry61]

Hi all, we have a large pond which we think is leaking;seems to be loosing more than evaporation. It holds approx 500,000 litres & is plastic lined (industrial reservour stuff) Question, is there a gismo that I can buy,borrow or bodge that will tell me where the leak is? I was thinking along the lines of resistance test between water (full of fish so no high volts) & surrounding soil;resistance would be lower where hole in liner & soil probe were close & closer would give lower reading. Help would be great, it's an awful lot of buckets to empty,regards Bob.

[Guest jhfozzy]

Found a couple of good google links,

 

Link

 

Link 2

 

From HERE

 

Best idea seems to be the first one, turn the pump off temporarily to remove the chance of it being that, if it keeps falling, watch the water level fall until it stops, then your leak will be near the water line. Obviously, remove the fish if it gets too low.

 

Sounds logical.

 

John.

Edited August 20, 2009 by Fozzy

[richyb66]

Are you sure the fish aren't drinking it?

[baj25]

Don't be daft Richy- if the fish are anything like me, they'll drink 2 pints and pee 4!!

[fry61]

We've done as suggested by Fozzy & corked the fish;no joy; there's near 500 feet of perimeter to check once/if the water stops going down; was hoping for an easier answer than spendind hours bent double checking the new water-line --- cheers for input so far.

[Guest jhfozzy]

Would it be worth using the dye method in one of those links? It suggests getting a dye block on a float and leaving it a bit to see where the (albeit small) current takes the dye.

Edited August 20, 2009 by Fozzy

[fry61]

Unfortunately Fozzy the "leak" is consuming about 100 litres an hour;every hour; so current flow would be very small,probably less than wind driven movement across the 3000sq.foot surface. On a weeky drain it's a big bucket-ful -- 17,000 litres & will take 30+ weeks to empty the pond;guess I'll have to keep looking,thanks for your input.