Pool opening checklist for Ohio

Later than people in warmer states and earlier than most Ohio owners do. The National Weather Service's 1991 to 2020 normals put the average last spring freeze at April 29 for Akron-Canton, April 23 for Cleveland and May 4 for Youngstown. Frost, which it defines as 36 degrees or colder, hangs on into mid-May in many places. You want the risk of a hard overnight freeze mostly behind you before water is sitting in the pump and filter again.

Once that point passes, sooner is better than later. Water under a winter cover warms up in May sunshine, and as it warms, the chlorine left from closing runs out and algae gets going. A pool opened in the first half of May usually needs one good shock and a few days of filtering. The same pool opened in mid-June, after a few 80 degree afternoons, can be green and take a week or more.

A practical target for most of our region is to open about two to three weeks before you want to swim. For a Memorial Day pool, that means early May. In the snowbelt parts of Geauga and northern Portage and Summit counties, a week later is often more comfortable.

• A fresh test kit or strips, and the chemicals you will need: chlorine, pH increaser and decreaser, alkalinity increaser, and shock
• DE powder if you have a DE filter, and your filter's manual
• A cover pump, a leaf net, a brush and a vacuum
• A garden hose long enough to top up the pool
• Somewhere clean and dry to store the cover
• The drain plugs and parts you stored in the pump basket last fall

Check the forecast. A dry day with no hard freeze in the following week is ideal.

Pump the standing water off the cover first. A solid winter cover in Ohio can be carrying rainwater, melted snow and a mat of leaves by April. Pull the heavy debris off with a leaf net, then pump. If you drag the cover off with that water and debris still on it, a lot of it ends up in the pool.

With a mesh safety cover, clear the leaves and release the springs from the anchors with the installation tool. Then screw or tap the deck anchors down flush so no one trips on them over the summer.

Clean the cover, let it dry fully, and fold it for storage. A cover stored wet mildews, and a folded solid cover left in the sun on the lawn can kill the grass under it in a day or two.

Pentair's opening advice starts here: before anything is switched on, remove the winterizing plugs and put the drain plugs back in the pump. Work through the pad methodically:

• Remove the winter plugs from the return fittings and the skimmer gizmos or plugs.
• Reinstall the drain plugs in the pump, filter and heater.
• Reinstall the pump basket, the skimmer baskets and any fittings stored for the winter.
• Put back ladders, rails and diving board hardware, checking the bolts.

Then look closely for damage. A plumbing line or pump housing that froze may have cracked over the winter, and Pentair notes that cracks in frozen pipes and lines do not leak until they thaw. Check fittings, unions and valve bodies for hairline splits before you run water through them, and again once the system is under pressure. If you see a crack, stop and call a pool professional.

Bring the water up to the middle of the skimmer opening. Fiberglass pools should have been closed with water in them, so this is usually a top-up rather than a refill.

Start the pump with the filter's air relief valve open so air can escape, and close it once a steady stream of water appears. Watch the pump basket fill and the pressure gauge rise. A variable-speed pump like the Pentair models in our packages can be run at a higher speed for the first day or two to move water through the filter quickly, then turned down for normal running.

If you have a DE filter, add fresh DE through the skimmer in the amount your manual gives, and write down the starting pressure once it is coated. Pentair's FNS Plus guidance is to backwash when the pressure reads about 10 psi above that original starting pressure. That number is your baseline for the season.

Check that the lights work, and test the GFCI protection on the pool circuits. If a heater is part of the system, follow its manual for startup rather than just switching it on.

Test before you add anything. The Centers for Disease Control and Prevention recommends a pH of 7.2 to 7.8 for home pools, and a free chlorine level of at least 1 ppm, or at least 2 ppm if you use stabilized chlorine or cyanuric acid. Adjust in a sensible order:

1. Total alkalinity first, because it steadies pH.
2. pH next, into the 7.2 to 7.8 range.
3. Then shock the pool to burn off anything that grew or collected over the winter.
4. Then bring free chlorine back to the normal range and hold it there.

Pentair points out that when pH climbs above 7.8 the water can cloud, scale and irritate skin, and chlorine does not work as well. That is why pH comes before the shock. Spring rain and snowmelt usually leave Ohio pools low in alkalinity and chlorine, so expect to add both.

Brush the walls and floor, vacuum out the sediment and run the filter continuously for the first 24 to 48 hours. Test again the next day and adjust. The CDC advises testing chlorine and pH at least twice a day once people are swimming, so start the habit now.

A winter of snow load and frost heave can knock a fence out of line, and a gate that closed perfectly in October may not in May. Before the first swim:

• Walk the whole barrier fence. Look for leaning posts, gaps near the ground and anything stacked against it that a child could climb.
• Open each gate and let it go. It should swing shut and latch on its own. The model code for pool barriers, Section 305 of the International Swimming Pool and Spa Code, calls for self-closing, self-latching gates.
• Check that every main drain cover and suction outlet cover is in place, uncracked and screwed down. The Consumer Product Safety Commission explains why: drain suction can trap a swimmer.
• Test any door or pool alarms.
• Put the life ring and reaching pole back out.

Fiberglass. Look over the surface for stains at the waterline and around fittings. Use the brushes and cleaners made for fiberglass, because harsh abrasives can dull the gel coat.

Vinyl liner. Look for wrinkles, pulled beading and small tears, especially at the steps and around the skimmer. Frost and a low winter water level can both move a liner. Catch a small tear early and it can often be patched.

Concrete. Check the plaster and tile line for chips, and look at the coping and deck joints, where frost does most of its work.

Do not panic, and do not dump everything in at once. Clear the debris, get the filter running, balance pH, then shock heavily and keep the filter going around the clock. Clean or backwash the filter as the pressure rises, because it will clog quickly while it catches dead algae. A bad start can take several days. Our guide to fixing green or cloudy pool water covers this in detail.

The first stretch after opening is when problems show themselves. Keep an eye on the filter pressure, because a sharp rise means it is catching a lot and needs cleaning. Check the water level daily for a week. A drop of more than evaporation on a warm, windy day can point to a leak that the winter caused. Look under the equipment for drips once everything has been running a few days. And keep testing. Spring in Northeast Ohio swings between cold rain and the first warm spell, and both throw the chemistry around, so small, frequent adjustments beat one big correction on a Saturday.

Plenty of Ohio owners open their own pools, and after the first year it takes a morning. The first opening is the one where a professional helps most, especially if you are not sure how the equipment was winterized. We offer pool openings, weekly cleaning and closings, and we check the equipment and water as part of it. Some customers have us open the pool the first season and then do it themselves after watching once.

Whichever way you go, write down what you did, the chemical readings and the filter's starting pressure. Next spring, that page saves you an hour.