How to Close a Ground Pool in Michigan for winter: Step-by-Step Guide

If you live in Michigan and own a ground pool, you already know how brutal the winters can be. Freezing temperatures, heavy snow, and ice storms can wreak havoc on your pool if it isn’t properly winterized. Learning how to close a ground pool in Michigan the right way will save you money, prevent costly repairs, and make pool opening in spring a lot easier.

In this guide, we’ll walk through everything you need to know about closing your ground pool in Michigan, including the supplies you need, the exact steps to follow, and some expert tips for Michigan’s unique climate.

Why Closing Your Ground Pool in Michigan Is So Important

Unlike warmer states, Michigan experiences extended periods of freezing temperatures. If water is left in the plumbing lines, skimmer, or pool equipment, it can expand as it freezes, leading to cracks, leaks, or even full equipment failure. Properly closing your ground pool ensures:

• Protection against freeze damage
• Longer lifespan for pumps, filters, and heaters
• Cleaner water when reopening in spring
• Lower maintenance costs over time

Skipping or rushing pool winterization in Michigan can lead to thousands of dollars in repairs come spring.

When Should You Close a Ground Pool in Michigan?

One Common question homeowners ask is: “When is the best time to close a ground pool in Michigan?”

The answer: mid-to-late September through October.

You want to wait until the water temperature is consistently below 65°F. If you close too early, you risk algae growth under the cover. If you wait too long, freezing weather can catch you off guard.

Pro Tip: Use a pool thermometer to track your water temp. When it dips under 65°F, it’s time to winterize.

Supplies You’ll Need to Close a Ground Pool in Michigan

Before you begin, make sure you have all the right supplies on hand. Here’s a checklist:

• Winter pool cover (safety cover or tarp-style)
• Water tubes or pool cover weights
• Winterizing pool chemicals (shock, algaecide, chlorine tablets)
• Air compressor or pool line blower
• Winter plugs for skimmers and return lines
• Pool antifreeze (specifically for Michigan’s freezing temps)
• Skimmer guard or Gizzmo device
• Telescoping pole, pool brush, and leaf net

Step-by-Step Guide to Closing a Ground Pool in Michigan

Here’s a detailed pool closing process designed for Michigan winters:

1. Clean Your Pool Thoroughly

Before winter, you want your pool water as clean as possible. Brush the walls, vacuum the bottom, and skim all debris. A dirty pool left under a cover all winter can turn into a nightmare when you reopen in spring.

2. Test and Balance Pool Water

Balanced water is key to preventing corrosion and scaling. For Michigan pools, check:

• pH: 7.2–7.6
• Alkalinity: 80–120 ppm
• Calcium Hardness: 200–400 ppm
• Chlorine: 1–3 ppm

Use a pool test kit and adjust chemicals as needed.

3. Add Pool Closing Chemicals

Michigan winters mean your pool will sit untouched for 6+ months. Add:

• Pool shock to kill bacteria
• Algaecide to prevent algae growth under the cover
• Winterizing chemical kit for long-term water care

Distribute chemicals evenly around the pool for best results.

4. Lower the Water Level

One of the most important steps in closing a ground pool in Michigan is lowering the water below the skimmer. This prevents freeze damage.

• For vinyl liner pools: drain to about 1 inch below the skimmer.
• For fiberglass/concrete: go 4–6 inches below skimmer.

Never drain completely — that can cause structural damage.

5. Blow Out and Plug Pool Lines

This is where most Michigan pool owners make mistakes. Any water left in the pipes can freeze, expand, and crack your plumbing.

• Use a shop vac, air compressor, or pool line blower.
• Blow out water from the skimmer, return lines, and main drain.
• Insert winter plugs to seal the lines.
• Add pool antifreeze to protect against freezing (extra insurance for Michigan winters).

6. Protect Pool Equipment

Your pump, filter, and heater need winter prep, too.

• Drain water from the pump and filter.
• Remove drain plugs and store them in the pump basket.
• Disconnect hoses.
• If you have a heater, follow manufacturer’s instructions to winterize it.

If you can store the small equipment indoors, its safer.

7. Install the Winter Pool Cover

A strong, secure cover is crucial in Michigan because of snow loads.

• Choose a mesh safety cover or a heavy-duty tarp cover.
• Secure it tightly with water bags, weights, or anchors.
• Make sure there are no gaps for debris or critters to enter.

FAQ’s On: How to close a ground pool in Michigan

Do I Need Antifreeze to Close a Pool in Michigan?

Yes. Because Michigan temperatures can dip well below freezing, pool antifreeze is strongly recommended for lines and skimmers, even after blowing them out.

How Much Does It Cost to Close a Ground Pool in Michigan?

• DIY Pool Closing: $100–$200 (supplies + chemicals)
• Professional Pool Closing Service in Michigan: $250–$500 depending on pool size and equipment.

Can I Leave My Pool Open All Winter in Michigan?

Not a good idea. The freeze-thaw cycles will damage plumbing, equipment, and the liner. Always winterize in Michigan.

What Happens If I Don’t Winterize My Pool in Michigan?

• Cracked pipes and plumbing
• Broken pumps, filters, or heaters
• Algae blooms in spring
• Thousands of dollars in repairs

Pro Tips for Michigan Pool Owners

• Use a Leaf Net: Place it over the pool cover to catch falling leaves. Makes spring opening much easier.
• Check the Cover Periodically: Heavy snow can weigh down a cover. Remove excess with a roof rake or pool cover pump.
• Store Accessories Properly: Ladders, rails, and skimmer baskets should be dried and stored indoors.
• Document Your Closing: Take pictures of how everything is winterized. It’ll help you reopen faster in spring.

Closing a Ground Pool in Michigan: DIY vs Professional Service

Some homeowners choose to DIY pool closing, while others hire professionals.

• DIY Pool Closing in Michigan: Cost-effective if you’re comfortable with the steps. However, mistakes (like not blowing out lines properly) can be costly.
• Professional Pool Closing in Michigan: Experts guarantee your pool is protected and often provide warranties on their work. Ideal for busy homeowners or those unsure about handling pool equipment.

Protecting Your Ground Pool from Michigan Winters

Closing a ground pool in Michigan is all about protection and preparation. By cleaning, balancing chemicals, blowing out lines, and installing a durable winter cover, you’ll ensure your pool stays safe through the coldest months. Come spring, you’ll be glad you invested the time — your water will be cleaner, your equipment safer, and your pool ready for another season of enjoyment.