Water loss in a negative edge pool can be confusing. Are you losing 8" in the surge tank or in the pool.

Normal losses of up to 1/4" per day look hugely magnified when they show up in a surge tank.

I just checked with DH. We lost 12 inches in 2 1/2 weeks from the pool itself. The spa is actually down about 2 1/2 feet.
Does this make sense?
Thanks!

Is the pool running and if so is it overflowing the negative edge?

I too was concerned when we were losing over 1/4 inch per day. My PB came back and found out that the skimmer was not fully grouted. After he repaired this we now have no water loss. I would start looking around the pool skimmer and definately call your PB. Hope this helps.

In hotter parts of the country, it is fairly typical to lose 100" or more a year but it will depend on the location and time of year. Winter is less than the yearly average while summer can be twice the average.

Here is a link that might be useful: Evaporation rates

You all are great - I really appreciate information!

We are in central California. Average temps lately are 28 at night and 68 in daytime.

The pool has not been running, and the pool cover has been on the entire time.

The PB was out this morning and claims it is normal. Now we are seeing rust around the light fixture rings. The rings and fixtures are all stainless steel and plastic, so they should not be able to rust. More mysteries!

Have the bonding circuit checked. If there is rust, it's usually due to either improper pool water chemistry or stray current causing corrosion.

Scott

Why isn't the pool running? Temps are 28 and the pool is only 2 months old. Has it been winterized?

"Have the bonding circuit checked. If there is rust, it's usually due to either improper pool water chemistry or stray current causing corrosion. "

My guess is that they didn't chip back the tie wires on the niche. Stray current against stainless usually turns black, not rust colored.

If your pool is not running, is it possible that the water is running back through the pipes to the surge tank and going out the overflow?

In Southern California- in weather thats 70's at night and mid to high 80's in the day with a pool temp of around 83 I get about 2" a week in evap. A little more 3" if I push it to about 85 87.

This seems to be about my running average.

Davegvg

Sorry - I guess, being a novice, I didn't give enough info. We are still building the house, so power to the pool is intermittent. We are just getting hooked into the grid this week (PG&E finished running lines to the property about 1 week ago and electrician is now connecting to the house & pool). We plan on keeping the pool active through the winter, so we are not winterizing. Is this an error? Current temps are about as cold as it normally gets all winter.

I have definitely checked the overflow - it is and has been for at least 2 weeks - dry.

racket: I would guess you are correct, since this PB seems to do everything wrong!

poolguynj: We immediately checked the chemicals - they are good. I will have DH check the bonding circuit. Please - what is a bonding circuit? DH might know (he's an electronic engineer), but I have no idea.

dancingsams,
With no equipment running, your pool and spa should not lose more than 1/4" to 1/2" per day. If your spa drops 2-1/2' in a couple weeks that's pretty dramatic. Sounds like you are not living in house and don't monitor on a daily basis. You have a lot of areas that can be actual water leakage and some that may make it look like a leak but could just be mechanical if you have several different water levels in the project.

Like I said, neg edges can be complicated, they can look like they're leaking when they're not, especially with the pump off. Multiple levels, water can siphon, or leak past check valves, equipment pad elevation, freeboard in your surge tank, there's all kind of things to look at way beyond a standard pool.

Your best next step would be to get the pool full and running, overflowing and circulating through the surge tank. Mark the water level IN THE SURGE TANK and monitor, with your autofill OFF. Measure after 24 hours. Keep in mind that if your pool, surge tank and negative edge wall face is, say, 1200 square feet combined, and your surge tank is, for example, 100 square feet, a 1/4" loss will look, in the surge tank, like a loss of 3 inches or more

Just to add a little to cascades comments. PB's don't all plumb negative edge pools alike. Some use skimmers in the pool and some don't. Some run the surge tank as an integral part of the system and some just use it like a water feature.
How it's plumbed is important to solving any problem you may be having. Or, how it's plumbed may be the problem. Good luck.

A scientific approach is needed when determining whether or not your pool is leaking. Timeframes and level losses need to be accurately measured and recorded. Speculating and estimating just leads you astray.

Here's a pretty definitive article:

Linky Thing: Evaporation Rates in the U.S.

Click on the contour map included to see the rate (in inches per year) for your area.

Good link. That generally explains why east coast pools don't need autofills.

We have been refilling the pool - it takes a while! DH is following your suggestions. It's true, we are not yet living in the house. That discussion goes in the "building a home" forum, as the house is not done yet - we are still in drywall stage. I appreciate the links, especially the one on evaporation rates. I will get back to you all when there is more information on our part.

THANK YOU!