How much does a natural swimming pool cost?

---

Common factors include:

• Total water area. Many designs need a regeneration zone in addition to the swimming area, so you're excavating, lining and landscaping more than the area you swim in.
• Type of filtration. A large planted zone needs more land and earthwork. A compact engineered biological filter needs less space but adds equipment.
• Materials. These include the liner or concrete, washed gravel or other filter media, and aquatic plants.
• Site conditions. Access for equipment, soil, slope and groundwater all matter.
• Local builder availability. Few contractors specialize in natural pools, and travel costs can show up in a bid.
• Extras. Heating, lighting, decking, fencing and landscaping add to the total.

Generally, they cost at least as much to build. One independent pool guide advises budgeting at least as much as for a well-built conventional pool with the same swimming area, and often more, mainly because of the extra excavation and filter area.  Savings on chlorine and other chemicals are real but generally modest. If you're comparing a natural pool's cost with an inground pool's, ask builders to quote the same swimming area, finishes and features.

You won't be buying sanitizers, but upkeep doesn't stop. Typical tasks include skimming, brushing the swimming-zone walls, controlling leaves in fall, trimming and thinning plants, and servicing the pump and filter. Every few years the filter bed may need a deep clean. HomeGuide estimates about $15 to $80 per month if you hire someone for routine maintenance. Electricity for pumps varies with the design and local utility rates. We haven't found a reliable published figure for it.

HomeGuide estimates $50,000 to $175,000 to convert an existing pool, which is about the same as building from scratch. Conversion is more than a filter swap. The pool usually needs room for biological filtration, along with new plumbing and possibly changes to the shell.

HomeGuide lists these related costs: permits at about $100 to $300, a pool heater at $1,200 to $6,000, and fencing at $2,000 to $13,500. Local fees and barrier requirements vary, so check them before you finalize a budget.

Some homeowners take on parts of a project themselves. But an NSP still has to be designed, engineered, permitted and built to the pool rules that apply where you live, and mistakes in filter sizing, circulation or barriers can be expensive to fix. If you're planning a DIY build, get a professional design review and check with your local building department first. If you wouldn't try to DIY a regular, chemical pool, don't think that a natural pool will be easier to build. It is not.

• Get several quotes. Ask more than one experienced builder, and look for natural pool professionals in the ASPNSP Member Directory.
• Compare like with like. Ask for itemized quotes that separate excavation, the shell or liner, filtration, plants, electrical, barriers and landscaping.
• Ask about upkeep. Find out what maintenance the builder expects you to do and what they offer as a service.
• Visit a finished pool if you can. Ask past clients what upkeep has actually involved.

You can send questions to info@aspnsp.org.

HomeGuide gives estimates by size: about $25,000 to $50,000 for 500 square feet, $50,000 to $100,000 for 1,000 square feet, and $100,000 to $200,000 for 2,000 square feet. These figures don't account for every region or site condition, and prices change over time.