The off-grid water access guide for wood-fired hot tub owners

One of the first questions our customers with remote properties ask is, “How will I fill my hot tub with no running water, and no pump hookup?”

It's a fair concern, but 25 years of building and installing hot tubs in off-grid locations in Canada and beyond have shown that it’s possible. The question isn't whether you can source water without a hose; it's which method best suits your property, whether that’s lakes, rivers, ocean water, rainwater tanks, or trucked water supply. 

Learn more about each source, their fill methods, and what to do with the water once you're done tubbing.

Key takeaways

• Water access at a remote property is a logistics question, not a reason to rule out a wood-fired hot tub

• The right fill method depends on what's nearby: natural water sources, stored rainwater, and trucked supply all have practical solutions

• Cold-weather sourcing takes a bit more planning, but doesn’t need specialist equipment

• How you treat the water going in determines what you can do with it when you drain it

Where does the water come from? Your sourcing options

The simplest approach is to pull water directly from your natural environment. With untreated water from a clean source, it's also the most sustainable.

Lake or river

A lake or river is the most common source if you own a remote property. The main variable is elevation, not volume. The higher the tub above the waterline, the more pump power you'll need. Run an inline hose filter before water enters the tub to reduce sediment in the tub.

Ocean or saltwater

For coastal properties, the ocean is an almost unlimited supply. Unfortunately, not all hot tubs handle saltwater safely. AlumiTubs are built from marine-grade aluminum, the same alloy used in aircraft and boat hulls, which makes them fully compatible. Most cedar or plastic-lined tubs aren't. 

Always plan to change the water within seven days of use to prevent mineral buildup on interior surfaces.

Ready to see the tub built for exactly this? Learn more about the AlumiTubs Wood-Fired AlumiTub

Well or rainwater tank

While well water works fine, it it often has high mineral content (calcium, magnesium, or trace metals like copper) that can affect water chemistry over time. Use a pre-treatment hose filter before filling to handle this.

Rainwater is naturally soft and free, but storage is a challenge. You need a cistern or elevated barrel large enough to hold a full tub’s worth. A 1,000-square-foot roof collecting 1.2 inches of rainfall at 85% efficiency yields roughly 650 gallons.

Trucked or jugged water

If your property doesn’t have a natural water source, water delivery works anywhere. A quality 

hose filter and attention to water chemistry will extend the duration of each fill.

See how AlumiTub owners reach remote properties

How to fill the tub when there's no hose

The method depends on how far you are from your source. Here’s a practical option for every setup.

Submersible pump and hose

This is the standard approach for filling from a lake or river. A 1/3 HP submersible pump drops directly into the water source and pushes water through a hose to the tub, flowing at roughly 40 gallons per minute, meaning a full fill takes around 30 minutes with a good hose. 

If your tub sits well above the waterline, or you're running a hose across 70+ feet of shoreline, use a 1-inch lay-flat hose rather than a standard garden hose to maintain a higher flow rate over the longer run.

12V solar pump setup

A 12V DC solar pump runs silently off a solar panel and battery bank, draws no fuel, and can be set up to fill the tub automatically before you arrive. Some remote property owners have switched from a generator to a 12V solar system for exactly this reason. The pump connects directly to the tub's drain kit for a bottom-up fill, which is more efficient than filling over the rim. If you’re spending regular time at your remote property, this is the setup worth building toward.

Generator-powered pump

When solar isn't viable, or winter temperatures compromise battery performance, a generator-powered pump is your reliable fallback. It's louder and needs fuel, but it works in extreme cold when other systems struggle. That makes it the go-to for winter fills from frozen sources.

Gravity-fed from a tank or elevated barrel

An elevated storage tank above the tub lets gravity do the work with no power required. Fill rates are slower than a pump, so this method is better for top-ups than for filling from empty. Pair it with a cistern large enough to hold a complete fill, and you have a fully off-grid water system with no moving parts.

Filling in winter when the water source is frozen

Cold weather doesn't stop the soak; it just changes the process.

When the lake is frozen over, simply cut a hole through the ice and pump from beneath. AlumiTubs customer Kevin MacLean has done exactly this in temperatures as low as -21°C, cutting through the ice with a chainsaw or ice auger and lowering a submersible pump into the liquid water below the frost line.

Plan for ice that can exceed two feet thick in northern climates. Once the fill is done, drain or blow out the hose immediately. Water left sitting in a hose at -20°C will freeze and block it.

If you'd rather avoid cutting ice, a pond de-icer in a storage tank keeps a water supply from freezing through winter. Water stored this way may need treatment with a spa shock or granulated bromine before use, depending on how long it's been sitting.

Tub volumes vary by model and manufacturer. AlumiTubs range from 315 gallons for the small model to 650 gallons for the large, so know your capacity before planning your winter fill setup.

How often do you need to refill your wood-fired hot tub?

Less often than you'd expect.

A well-insulated tub retains heat between soaks, and your water-care approach determines how long the water stays clean. For short, chemical-free fills (like a weekend at the cabin or a few days of soaking), water can enter and exit without any treatment.

"Remote property owners often try to use water from their natural environment," says Laura Anderson, our owner and managing director. "When the tub is filled with water from a natural resource and left untreated, it can be released back after without consequence, conserving resources and working with nature rather than against it. This fresh-fill simplicity is a very elemental way to experience the hot tub."

For saltwater fills, change the water within seven days. For longer stays with treated water, always follow your water care routine.

What to do with the water when you're done

Connect a garden hose to the drain kit and run it where you want the water to go.

If you haven't used any chemical treatments, untreated water from a natural source goes straight back where it came from: lake, river, ocean, or garden. 

If you've added bromine or chlorine, neutralize the water before draining it anywhere near a natural body of water, as active sanitizers are toxic to aquatic life. Check the level with test strips, add a sodium thiosulfate neutralizer, and retest after 15 minutes. Once it reads clear, drain onto vegetated ground where water can filter through the soil before reaching groundwater.

The chemical-free approach, which most AlumiTub owners at remote properties prefer, skips this step entirely.

Water access is a solvable problem

Water access at a remote property is a logistics question, not a reason to rule out a wood-fired hot tub. Lakes, rivers, ocean water, rainwater, and trucked supplies are all available methods to fill up your hot tub in the wild. While the filling and draining methods will change depending on your site, the outcome doesn't. Turns out, nature is pretty good at providing.

AlumiTubs are built from marine-grade aluminum that handles saltwater and natural water sources without issue: no corrosion, no special treatment, no complicated winterization. Reserve now, pay later. Your guaranteed ship date is assigned at order.