Evaporation, or leak?

[Bluerooster]

Or both? Temps in the 90's for about 10-12 hours a day, Not a cloud in the sky, pond in full sun, full time, ~400sq ft, surface area, 3 sets of falls. have bean losing about 2" a day.

Nothing in danger, but I'm tired of having to top it up all the time. That's about 320 gallons a day!

 

[Lisak1]

1st way to test - turn off any waterfalls or pumps. Most "leaks" turn out to be in the plumbing. But at those temperatures I'd hesitate to try it during the day. You can also check for damp spots around the waterfall and the entire perimeter of the pond. A low edge can cause a surprising amount of water loss. Things can settle and pull the liner down allowing for water loss.

Can you try not adding water and see if it continues to lose water? That's another way to find out if it's a low edge or a liner leak up high.

 

[Ray G]

It is a leak! In Australia we would typically have over 100F temps often in summer. Long summers. My evaporation would be up to 1/4 inch per day max. At your rate of loss (2" per day) that is over 1 foot per week.

 

[mgmine]

Go you have a waterfall? If so then it could be splashing out.

 

[poconojoe]

Agree with Lisak1. The first thing you should do is take all the plumbing out of the equation by shutting off you pump(s). Do it at night when it's not as hot. Top off the pond and leave it till morning. It would be advisable to have an aerator running during this time to keep the water oxygenated. If you don't have an aerator, use a pump to just get some surface splashing going.

 

[poconojoe]

Go you have a waterfall? If so then it could be splashing out.

Good point. A waterfall is the culprit in many situations and for many reasons. Splashing out, no liner underneath the rocks, poor shape of a liner under the rocks, poor design and placement of the rocks, hole in the liner under the rocks, and as mentioned...leak in the plumbing feeding the waterfall.

 

[Lisak1]

It is a leak!

That's what most automatically think. But a "leak" generally isn't a leak at all. Much more likely that it's a low edge or a plumbing failure.

And water loss from evaporation varies dramatically from one area to another. What you have to do is figure out what is normal for YOUR pond.

 

[Ray G]

I agree with the plumbing failure. I include that as a leak. I dont mean just the liner. Plumbing leaking is often a bit issue.
Taking everything into account as Bluerooster estimates the daily loss at 320 gallons a day it is hard to imagine that is splash from a waterfall or anything above ground as I am sure we would all notice 320 gallons per day splashing beside the pond. however plumbing leaking below ground OR water leaking behind a waterfall could easily be the culprit as that is a lot of water lost each day.
If it were evaporation then the water would become very hard quickly as the salts in the water are not evaporating at all. that is a lot to replace each day. Lets assume it is a 3,000 gallon pond then the entire volume of water is evaporating in less than every 2 weeks. THat is a lot of waterchange.

 

[poconojoe]

Now that you mention it, 320 gallons a day is an awful lot of water!
I once had a softball sized hole in my liner on the bottom of the pond. That was 300 gallons a week to top off. The OP is losing 320 a day! That's a major leak!
I would think there would be some obvious evidence somewhere with that amount of water loss.
If the surrounding soil isn't wet, then it has to be escaping underground somehow.

 

[brc]

2" a day in any pond is a lot.. That's gotta be a leak.

Splashing from the waterfall could maybe do it - just a tiny bit of water being out around the clock can add up to a lot of gallons. But, it's unlikely, especially if the pond didn't do this last year.

More likely, is that some organic material has affected the flow of water around one of the waterfalls. Based on the time of year, I'm guessing you are bringing an existing pond back up. In my experience, there are often leaks this time of year due to dead leaves and such causing the little bit of water that goes behind a waterfall, to get "stuck" back there, and find its own way out.

 

[addy1]

I have to walk our steam and fix all sort of issues after winter, deer walk it, ground hogs, plants take off in the spring and over grow, rocks shift, a constant fix it job. Once it has run a bit and and I fix all the "leaks" all is usually fine for the summer, except yanking excess plant growth.

 

[Bluerooster]

When I first installed the bog, I had a leak in the liner. Which was easily detected. The ground was pretty wet and would not dry up.
Got that repaired, and have seen no sign of wet ground anywhere around the pond since. I made up a gauge of sorts, to determine the exact amount of water loss, per day. I'll get back to you with that figure in about 4 more hours. (it may be less than my initial estimation) Judging exact water loss looking at the current level, compared to the water line on a sloping surface can be misleading.

 

[poconojoe]

Bluerooster, I have a small digital meter that screws onto the end of my garden hose. This way I know exactly how much water I'm adding. You can get them on Amazon for around $15 U.S.

 

[Ray G]

When I first installed the bog, I had a leak in the liner. Which was easily detected. The ground was pretty wet and would not dry up.
Got that repaired, and have seen no sign of wet ground anywhere around the pond since. I made up a gauge of sorts, to determine the exact amount of water loss, per day. I'll get back to you with that figure in about 4 more hours. (it may be less than my initial estimation) Judging exact water loss looking at the current level, compared to the water line on a sloping surface can be misleading.

Good idea. As your original estimate would lead to your whole pond being empty in 8 days (which is a heck of a lot of waterloss.

 

[Bluerooster]

OK, as of right now, 24 hours after top up. I've lost exactly 1 inch. (about 150 gallons give or take) I suspect a small leak somewhere, along with evaporation. I'll be out of town all this week, so I'll shut down the pump this weekend, and see what happens over night.