How do I open my pool in the spring?

Open a pool in this order: clear and remove the cover, put the hardware back, bring the water to the right level, start the filter, then test and balance the water before anyone swims. The water work is the part that matters. A pool that looks clear in April can still have the wrong chemistry, so do not skip the testing.

Plan the day

Pick a dry, mild day and expect it to take most of a weekend: the cover work is an afternoon, but the water needs a day or two of filtering before it is ready. A health department guide for pool operators, from the Portsmouth Health Department, notes that refilling can take time too: its spring checklist says filling "may take several days to refill pool", so plan ahead.^[1] You will usually only top up a pool that held its water over winter, but if yours was drained, the same warning applies.

The same guide treats the weeks before opening as the hard part. It says the effort you put in before opening day is what lets the equipment do the work for you the rest of the season, and that the end of the operating season is the best time to inventory your equipment, prioritize and complete repairs, and prepare your facility for winter weather.^[1] If you did not do that last autumn, now is the time to look over the ladder, rails, skimmer lids and pool deck for damage.

Remove the cover and reinstall hardware

Before you pull a cover off, pump or siphon off the standing water and brush off leaves so debris does not slide into the pool. Clean the cover, let it dry fully, and store it somewhere dry and secure. Mildew and mice are the usual reasons covers fail early.

Put back the ladders, handrails, diving board and anything else you removed. The guide's winter checklist for public pools tells operators to remove ladders and diving boards and store them inside,^[1] so if you did the same, put them back now. Check that every bolt is snug and that nothing wobbles before anyone uses it.

Set the water level and restart the filter

Fill with a hose until the water sits at about the middle of the skimmer opening, so the skimmer can draw water without sucking air. Reinstall any plugs and gauges you removed, and check the pump basket, the skimmer basket and the pump lid seal.

Then start the pump at its own switch and watch the pressure gauge settle. Water should flow from the returns and the pump should prime within a minute or so. If it will not prime, shut it off rather than letting it run dry. Run the filter around the clock for the first day or two. Follow the filter manual for startup; sand, cartridge and diatomaceous earth filters each have their own procedure. Valves that sat all winter can stick, and the guide recommends operating all valves at full range to prevent sealing up.^[1]

Leave heaters, automation panels and anything wired or gas-fired to a licensed pro. Do not restart a heater or open its gas line yourself.

Test and balance the water

Buy fresh test reagents or strips. The Portsmouth guide says all reagents should be replaced at the beginning of each new season, and that test kits are not 100% accurate, so treat them as close estimates and keep them cool and dry.^[1] Its warning is plain: "Operating a pool without testing is like driving a car with your eyes closed."^[1]

Work through the readings in this order.

Balance first. The guide says that when filling a pool at the beginning of a season, it is important to get the water in balance as soon as possible.^[1] Adjust total alkalinity before you chase pH.

pH. The guide says pool water should be kept at a pH of 7.2 to 7.8, with 7.4 the optimum.^[1]

Chlorine. The guide says the Portsmouth Health Department follows the Virginia Department of Health standard under which the free available chlorine residual for pools is continuously maintained within the range of 1.0 – 3.0 parts per million.^[1] That is a public-pool standard, so check your chlorine product's label for a home pool.

Stabilizer. If the pool is outdoors, cyanuric acid, or stabilizer as it is commonly known, should be added to pool water at the beginning of the pool season;^[1] once the proper level of stabilizer is achieved (40 – 60 ppm), the guide says to check it weekly.^[1] Your chlorine product may already contain it, so test before you add more.

Shock if the water is dull. Super chlorination means raising the free chlorine residual of the pool water to 5 to 10 ppm.^[1] Do it in the evening and follow the product label.

When you add acid or other chemicals, keep swimmers out. The guide says acids and bases may be directly added to pool or spa water as per label instructions as long as there are no people in the water, and the pool stays closed until the chemicals are completely dissolved or dispersed.^[1] Never mix anything with chlorine except water.^[1]

Stop and call a pro if

• The water is green, black or stays cloudy after a few days of filtering and corrected chemistry. There may be a circulation or filter fault.
• The pump will not prime, leaks or makes a grinding noise.
• There is any electrical or gas issue: a light that trips the breaker, a heater that will not start, a buzzing motor or a gas smell.
• The shell, plumbing or deck is cracked or leaking. The Board for Contractors says that if the work you are considering is valued at $1,000 or more, a valid Virginia Contractor’s License is required.^[2]
• The water level dropped a lot over winter. That points to a leak.
• You are unsure which chemicals to use or in what amounts.

Getting help in Virginia

If you would rather hire it out, read how much it costs to open and close a pool in Virginia and whether to open and close it yourself or hire a pool company. For regular care after opening, see how to clean a swimming pool. Browse pool and spa services or more pool and spa answers.

When you are ready, describe the job once and local pool pros quote it.