Scottsdale Pool Acid Wash The pool was drained and now the plaster is cracked
This page exists because it is the most expensive mistake in the subject, and it is almost always made by someone trying to avoid a $400 to $800 job.
Why an empty pool is a liability, not a clean slate
A pool shell spends its life holding tens of thousands of pounds of water. The plaster chemistry and the structure both assume that water is there. Remove it and three things start working against you.
Heat. Plaster is meant to stay wet. An empty shell in Scottsdale sun in July becomes an oven; the surface dries and shrinks, which produces crazing, a fine spiderweb of surface cracks. That can happen in hours. Draining in the afternoon and getting to it tomorrow is how a cosmetic job becomes permanent.
Hydrostatic pressure. Groundwater beneath the shell was balanced by the water inside it. Empty, the shell can be pushed upward. Across most of the Valley the water table is deep enough that this is uncommon, but it is likelier after sustained monsoon rain or next to heavy irrigation, and a popped pool is not repaired cheaply.
Time. The longer the shell sits empty, the worse both get.
How a proper drain avoids it
The method is mostly sequencing:
- Drain, wash and refill as one continuous operation. The pool never waits empty for a second visit.
- Work the cool part of the day, and avoid peak summer for elective work where the schedule allows.
- Keep the surface wet between stages rather than letting it bake.
- Check the hydrostatic relief valve where the pool has one; that is what lets pressure equalise instead of lifting the shell.
- Start the refill immediately.
- Balance on refill, because Valley fill water is hard and a freshly acid-washed surface is chemically raw.
What you are really buying is that sequence. The acid itself is cheap.
Where the water goes
Worth raising because it surprises people. Draining tens of thousands of gallons has rules attached that vary by jurisdiction, and the legal destinations are generally the sewer clean-out or an approved discharge point, not over the back wall.
Chlorinated or acid-treated water going somewhere it should not is a genuine problem. Ask the city before you drain.
If it has already happened
Surface crazing. Fine hairline cracking across the plaster. Frequently cosmetic, and worth having looked at before assuming the worst.
Wide or structural cracks. Shell repair, a different trade. An acid wash does not address it.
A shell that has visibly lifted. Specialist structural work, and a serious number.
Know which of the three you have, because only one of them is acid wash work.
What it costs to do it properly
| Work | Price |
|---|---|
| Drain and clean, no acid | $200 to $450 |
| Green pool cleanup | $250 to $600 |
| Acid wash | $400 to $800 |
| Large or luxury pool | $700 to $1,200+ |
From the pricing page. Against a cracked surface or a floated shell, that is the cheap end of the possible outcomes.
Get a quote
If the pool is currently empty, say so first so it is treated as urgent, because time empty is the variable that matters. We cover Scottsdale, North Scottsdale, South Scottsdale, Paradise Valley, Fountain Hills, Cave Creek, and Tempe.
Frequently Asked Questions
How fast can a drained pool be damaged?
Faster than most people expect. Plaster is meant to stay submerged; an empty shell under a Scottsdale summer sun gets very hot and its surface dries out fast. Crazing can appear within hours on a hot day, which is why a professional drain, wash and refill runs as one continuous job rather than being left open overnight.
What is pool popping?
Groundwater pressure pushing an empty shell upward, because the water that was holding it down is gone. It is much more common in high water table areas than across most of the Valley, but it is not impossible here, particularly after sustained monsoon rain or beside heavy irrigation. It is catastrophic and not cheaply repaired.
Where am I allowed to discharge the water?
That is set locally and it is a real requirement rather than a technicality. Tens of thousands of gallons of chlorinated or acid-treated water has limited legal destinations, generally a sewer clean-out or an approved discharge point rather than the street or a neighbour's yard. Ask the City of Scottsdale before you drain, and any legitimate pool company will already know the rules.
Can crazed plaster be repaired?
Surface crazing is often cosmetic and sometimes improves with a proper wash and balanced chemistry. Structural cracking in the shell is a different trade and an acid wash does not address it. Get a plain answer on which you are looking at before paying for a wash.