Cresswater Natural Pools · Living-water design & build · Marrow Brook & the Whitlow Fen · Est. 2012

Chlorine was never the point. Clear water was.

Cresswater builds pools with no sanitizer in them at all — a planted regeneration zone doing the filtering, gravel and root and zooplankton instead of chemistry, and water that reads like the brook the town is named for. Ninety-six living pools across the Fen, swum in every summer since the first one, and not a jug hauled to any of them.

Issue 9 of the water journal mailed this spring · 96 living pools since 2012 · zero sanitizer dosed, ever · (555) 026-4819

Services & rates

Living water, priced from

Prices are from last season’s Whitlow Fen builds and cover dig through the first clear season on a straightforward lot; clay, springs and listed gardens are priced at the free walk. Every build carries the water ledger — a season-by-season record of what the zone did — and the conversion line exists because most pools are one planted bay away from water you would rather swim in.

Natural pool, full buildfrom $88,000

Swim zone and regeneration zone, EPDM membrane, low-flow circulation, planting, first clear season

Chlorine-to-living conversionfrom $41,000

Your existing shell re-zoned: a regeneration bay added, plumbing re-aimed, the chemical habit retired

Swim pondfrom $56,000

The informal version — clay-lined, planted margins, a dock instead of a deck

Regeneration retrofitfrom $18,400

A planted bay for a pool that keeps fighting its own chemistry — the filter stays, the jugs go

The habitat plantingincluded year one

Eleven species graded by depth, stocked at commissioning, weeded and thinned twice a season

Living-water care plan$96 / month

Monthly visit: plant thinning, substrate rinse, flow check, the water ledger

A planted regeneration zone beside a natural swim pool

How the water clears

Half the pool is a garden

A living pool is two bodies of water in one shell: the swim zone you float in, and a regeneration zone of gravel, rushes and watermint that the whole volume passes through roughly once a day. The plants take up the nutrients, the biofilm on the gravel eats the rest, and the zooplankton graze whatever would make the water green. No sanitizer, no algaecide, no smell — and the hydraulics are the opposite of a chlorinated pool’s: slow, gentle turnover on purpose, because the filter is alive and rushing it would wash its dinner away.

Services

The living system, in order

01

The regeneration zone

Between a third and half of the surface, graded from shallow gravel to planted shelves: rushes, watermint, iris, hornwort — eleven species stocked by depth at commissioning. This is the filter. It is also, half the time, the part of the garden people like best, and the frogs move in without being asked.

02

The swim zone

Membrane-lined, stone-finished, two metres at the deep end and free of plants on purpose — nothing grows where people swim, because everything that clears the water lives next door. The boundary is a wall or a shelf, drawn at design, and the finish underfoot is the same pebble aggregate a conventional pool would wear.

03

Circulation, slow on purpose

One low-energy pump moves the whole body through the planted zone about once every twenty-four hours — a deliberate contrast with the four-hour filter turnover of a chlorinated pool, and the number every conventional builder who visits one of ours asks about first. The water also passes a skimmer and a fine drum screen, because leaves are leaves in any philosophy.

04

The season and the ledger

Spring: the zone wakes, the water clouds briefly, then clears as the zooplankton catch up — the ledger photographs it every year as proof of the pattern. Autumn: the margins are cut back, the net goes on, and the care plan’s monthly visits keep the whole thing honest for households who would rather swim than garden.

The Cresswater promise

Clear by biology, not by dose

The journal is the proof and the ledger is the receipt: fourteen seasons of photographs showing the same spring cloud clear into the same June water, across ninety-six pools. No sanitizer was dosed into any of them, no algaecide, no UV lamp even — just surface area, plants, grazing animals and patience, in that order. The guarantee below is short because the system it describes has been running since before some of our clients were born.

The first clear season

A living pool clouds green for a few weeks in its first spring while the biology establishes, then clears and stays clear. If the water has not settled by the Fourth of July of the first season, the correction visits are ours until it does — ninety-six pools, and the clause has been needed twice.

How it goes

Walk to first swim

The same sequence on every job — the only variable is your project.

  1. Week 1

    The walk & the water test

    We walk the lot, test the well or mains water you will fill with, and read the sun — a regeneration zone is a solar-powered filter, and shade decides its size. The concept and the fixed quote follow inside ten days, planting plan included.

  2. Weeks 2–4

    Dig, membrane, margins

    Excavation of both zones in one shape, the EPDM membrane in a single sheet with no field seams, gravel substrate washed in by the truckload, and the shelf grades set to the planting plan — every species has a depth it insists on.

  3. Weeks 5–6

    Plant, fill, circulate

    The circulation set goes in — one small pump, a drum screen, the skimmer — then the fill and the stock plants, and the commissioning photographs that start the water ledger. The pool now does its green-to-clear trick; we tell you it is coming so nobody panics.

  4. Season one & after

    Clear water, kept

    Monthly care-plan visits through the first season, the ledger photographed at each, and the handover hour where you learn the two tests a living pool actually needs — clarity against the disk, and nothing else. No jugs were ever ordered.

2025 — 2026, the Fen

Ponds we have built

Six living waters from last season, photographed in the hour they are used — which on the Fen is late afternoon, with tea. Owners will walk you their regeneration zones with more pride than their decks.

The Marberry plot
The Marberry plot — 34-ft swim zone, regeneration bay behind the wall
Whitlow Fen conversion
Whitlow Fen conversion — chlorinated 1996 shell, living since May
The Hollow swim pond
The Hollow swim pond — clay-lined, dock and planted margins
Brookside retrofit
Brookside retrofit — the planted bay that retired the jugs
The zone in July
The zone in July — watermint in flower, water reading four metres
Aerial of the Alder lot
Aerial of the Alder lot — swim zone left, filter right, frogs throughout
96
living pools built across the Fen since 2012
24 hr
whole-body pass through the planted zone — slow on purpose
0 mL
sanitizer dosed into any of them, in fourteen seasons
11
plant species in the standard habitat mix, graded by depth

Fair questions

Questions about living water

The five every Fen kitchen reaches once the word “no chlorine” lands. The water line answers seven to five, Marrow Brook time.

Is it really safe to swim in untreated water?

It is treated — by biology instead of a bottle. The zone strips the nutrients algae would eat, the zooplankton graze the rest, and the water passes a drum screen and a skimmer like any pool’s. European living pools have been swum in for decades on exactly this design; ours test clearer than the brook beside them most summer weeks. What you give up is the sanitizer residual, and what you get back is water your eyes and swimsuits stop complaining about.

What about mosquitoes?

Mosquitoes want still, sterile water — a larvae-eating paradise with no predators. A living pool is the opposite: circulating, predator-full, with dragonfly larvae and daphnia hunting the surface film. The Fen’s ninety-six pools are the town’s least mosquito-y acreage in July, and the journal has run the count twice to prove it.

How much work is a living pool?

Less than a flowerbed and more than a chlorinated one: margins cut back in autumn, plants thinned in spring, the drum screen rinsed monthly. The care plan does all of it for ninety-six dollars a month, and about two-thirds of our households take it — the rest take the pruning hooks and the ledger, and do it themselves with the journal’s calendar.

What does a Fen winter do to it?

Nothing dramatic, which surprises people. The zone drops its foliage, the pump slows to its winter trickle, ice sits on the swim zone while the planted margins sleep under it, and spring brings the brief green cloud that clears by June. The ledger photographs the same pattern every year — it is the biology’s heartbeat, and after fourteen seasons we stopped worrying about it in writing.

Can our chlorinated pool become one?

Usually, and it is the quieter half of our work: a regeneration bay added beside or behind the shell, the returns re-aimed to feed it, the equipment pad simplified — the salt cell or the chlorinator comes out, and the jugs go back to the store. The conversion line on the rate card covers it, the walk decides the size of the bay, and the finish you already own, pebble or plaster, stays exactly where it is.

Word of mouth

The Fen, swimming clear

We expected a pond and got a pool that happens to be alive. The water is soft in a way I cannot describe except that the kids stopped asking for goggles, the regeneration bay flowered all June, and the monthly visit is fifteen minutes of pruning and a photograph. Fourteen seasons of jugs, gone in one conversion.
Bettina Larssen · Conversion, Whitlow Fen
The first spring clouded green and I called in a panic. They sent the ledger instead of a chemical — the same cloud, the same week, photographed across thirteen pools — and it cleared on the exact schedule they said it would. That ledger is now my favourite thing about the property, which is a strange sentence about a spreadsheet.
H. Okonkwo-Brandt · Full build, the Hollow
Two frogs, one dragonfly squadron, and water my mother, who grew up on a lake, pronounced cleaner than her childhood swimming hole. The zone does the work, the pump costs less to run than the old chlorinated one did, and my son has learned every plant by name. We swim from May to October and I never once bought a jug.
The Ferreira-Nash family · Swim pond, Brookside

Free walks across Marrow Brook & the Whitlow Fen · (555) 026-4819 · hello@cresswater.example

Come walk a living pool

Tell us the yard and the water you fill with. The walk is free, the concept and planting plan follow inside ten days, and the first clear season is guaranteed in the contract. hello@cresswater.example