Among the problems: contamination from raw sewage and oil, vinyl pool liners ripped by downed trees and other debris, and electronic pool components corroded by salt water, according to pool professionals. Some of the contaminants are chlorine-resistant.
Extra costs range into the thousands of dollars.
"The closest to the shoreline, we're seeing almost like a black tar -- the odor is almost like sulfur -- in the very bottom of the pool," said Robert Grant, president of Spa & Pool Medic Inc., a Bethpage- and Shoreham-based company. "Some of the stuff is so bad that in the concrete pools, we actually have to resurface the pools."
Concern over post-Sandy pool contamination has prompted the state Health Department to draft new recommendations that soon will be shared with local health departments, said spokesman Peter Constantakes.
The pool at Marcel and Susan Junger's Atlantic Beach home -- midway between Reynolds Channel and the Atlantic Ocean -- recently featured murky, dark-green water with brown floating particles.
Susan Junger, 71, said Sandy left the pool cover "loaded with disgusting goop," some of which leaked into the pool.
"It's horrible," she said. "All of the sewage and all the crap from the ocean and the streets landed in my pool."
Pool industry in deep
Sandy's toll has put extra pressure on the pool industry during its busiest season from April to July, said Lawrence Caniglia, executive director of the Northeast Spa & Pool Association trade group.
Ten additional staff to service damaged pools were hired by Bay Shore-based Ultimate In Pool Care, said owner Ed Cohen, while employees average 12-hour workdays at Long Island Swim-Pool Service in Island Park, president Barry Vineberg said.
"We actually found pools that were completely filled with salt water, with fish swimming in them," he said. "We've never seen anything like this."
Andy Levinson, owner of Jet Line Products -- a Farmingdale-based distributor of pool supplies and equipment to dealers -- said his company has "already sold double" of a popular pool heater compared to last year, "and that's directly related to storm damage."
"Thousands of pools were affected. Many people don't even realize the damage they've had yet," he said. "They were worried about their house, not their pool."
Christopher Cawley, 50, of Massapequa, said trash, wooden pier remnants and sand filled his pool. But with 3 feet of water in the crawl space of his house, Cawley said, "The pool was the least of our concerns."
After opening the pool earlier this month, Cawley discovered cracked tile and was advised that the pool bottom needed to be plastered.
The post-Sandy focus for Ira Aronson, 65, of Oceanside, was on repairing his roof and clearing out the foot of water in his basement. "Now the pool is the priority because it's starting to get warm and I have five grandchildren that want to go in it," he said.
Aronson said he had to replace underground wiring, a pump and heater. "I'm in the neighborhood of $12,000 to $15,000," he said, adding he did not have flood insurance. "The pool is all out of pocket. . . . It's very difficult to swallow."
Owners tackle the expense
Flood insurance policies purchased from the National Flood Insurance Program and managed by the Federal Emergency Management Agency do not cover swimming pools, said FEMA spokesman Ray Perez. The agency's individual assistance program doesn't extend to pools either, he said.
Grant said a lack of insurance coverage is leading many customers to keep pools closed "because they just can't afford the extra out-of-pocket expense to do any kind of repairs from the storm."
Repair costs are even greater for municipalities or commercial businesses that operate larger pools with more expensive equipment.
Five of the 23 pools owned by Hempstead Town sustained Sandy damage so far totaling more than $220,000 for new pipes, pumps and valves, said spokesman Mike Deery.
The Olympic-size pool at Lido Beach's Malibu Shore Club -- owned by the town and operated by Dover Group NY -- sustained about $50,000 to $100,000 in electrical work and other damages, said Dover president Butch Yamali.
Seawater flooded pump rooms at Babylon Town's spray parks at Venetian Shores in Lindenhurst and Tanner Park in Copiague, said Deputy Town Supervisor Tony Martinez. The town spent about $330,000 on engineering and electrical repair work, said director of communications Kevin Bonner.
The spray parks will open June 22 as scheduled, said Martinez, adding, "We want to make sure that our facilities are available to our residents who have suffered so much due to Sandy and may not be able to use the pools in their backyards."
HOW TO OPEN A DAMAGED POOL
Soon-to-be-issued recommendations from the New York State Health Department:
Pools should be cleaned, disinfected and refilled with clean water. When the circulation system is running, pool water should be disinfected following guidelines for inactivating Cryptosporidium, an extremely chlorine-tolerant parasite often associated with sewage-contaminated water.
If structural repairs are needed or electrical components flooded, contact local building code enforcement officials to determine whether an inspection or electrical compliance certificate is required.
Consider consulting with an experienced pool professional or a licensed engineer if floodwaters entered the pool.
Check with a pool design expert to avoid possible structural damage from draining pools.
Be sure pool chemistry and clarity have returned to normal operating levels before swimming.
SOURCE: STATE HEALTH DEPARTMENT
Recommendations from pool experts:
Hire a qualified electrician to inspect electrical components and outlets before trying to start the motors or components yourself.
Consider changing your liner if the pool experienced flooding by seawater; oil in the water will make the liner more brittle.
If purchasing a new pump, check with a qualified dealer about a $400 LIPA rebate for energy-efficient pumps.
Ask a pool professional to dump pool water if any surge water entered the swimming pool; do not try to do it yourself.
SOURCES: INDUSTRY EXPERTS