Hi Morana,
Generally most native animals that find their way in to a Natural Swimming Pool are welcome. Frogs are fine, and the occasional turtle may dig around and stir up sediments but shouldn't be a problem.
Fish eat mosquitoes but they also eat the natural predators of mosquitoes.
A Natural Swimming Pool contains so many other creatures that predate mosquito larvae, dragonfly larvae, water boatmen, tadpoles, newts, the list goes on, that the mosquitoes don't stand a chance.
Strange as it may seem, a forgotten bucket of water will be teeming with mosquitoes within days, but the pool will be completely free of them. Indeed, I have not seen any mosquito larvae in any Natural Swimming Pool.
Hi Jesse,
my larger pool (20m x 15m total area with a 5m x 11m swimming zone) cost me around £6000. This doesn't include my labour of course. Probably a fair ratio would be around 50-60%
Yes they are certainly aesthetically more pleasing and far easier to maintain than a conventional outdoor pool.
Yes I agree.
Natural Swimming Pools, fit so neatly within permaculture principles and have the power to engage a wider audience, rekindling the notion a lot of us have forgotten through detachment, that being immersed in nature, is being healthy!
Hi Jason,
Yes, runoff water is not good for Natural Swimming Pools because of the nutrients it brings in. The pool should be constructed to prevent this entering.
There is no reason why any lining technique shouldn't be applied to Natural Swimming Pools. Clay pools should be deeper to reduce the sediments kicked up by swimmers. A synthetic liner is easier to install and easier to clean if debris becomes an issue.
1) The entire volume of water should be circulated within 24 - 48 hours.
2) There is no disadvantage in introducing air. A waterfall is mainly for cosmetics but should not cause any problems.
3) Circulate the water in the swimming area vertically to disturb the water stratification (i.e. the cooler lower water churned up with the upper warmer water.)
4) There are calculation/approximation methods available, but even measuring all the parameters necessary (wind speed, vapour pressure, etc) is tricky and will only give you a snapshot of the evaporation rate. It is best to get information from a local pool supplier for the average water loss through evaporation.
5) I know of no issues myself. Natural Swimming Pools have been made in Australia and work fine. I found a paper on a Caribbean wild ponds and incredibly they contained no mosquitoes. Just like in Natural Swimming Pools, predators, like dragonfly larvae, control them.
And sadly, as far as this summer is concerned, the UK has has not warmed up that much since you've been away.
Hi Katrin,
sadly fish won't work with a Natural Swimming Pool. In order to keep the water clean and clear for swimming the nutrient levels have to be kept low. Plants then compete for those nutrients and suppress algal growth. The fish will have to be fed and fish food is a whopping great dose of nutrients being dropped in the water. Even if the fish just feed off plants in the pool, sediments will be introduced as the fish uproot the plants and it is those plants that are needed to condition the water.
Food plants - yes! I'm trying with water cress, mint, rhubarb and even water lily tubers (although I haven't eaten one yet because they are too valuable and are supposed to taste like potato)
Ever eager to explore potential new food from the pool, I gathered a bucket full of water snails, boiled and shelled them and fried the morsels with garlic. They were horrible. Like pieces of car tyre but grittier. I fed them to the chickens. It's a bit convoluted but those eggs were a yield from the pool.
Hi Shawn,
I see no reason why this could not be made to work. In fact, I was planning to experiment with this idea. I have the poly tunnel tubes ready to go over my small pool to start experimenting. I plan to enclose the whole pool and see what happens.
Hi Graham,
the only maintenance is pulling out some organic matter in the autumn, usually just dragging some decaying vegetation out with a rake. This removal of organic matter will compensate for the nutrients the pool has collected throughout the year.
The key is to construct the pool so as to minimise the nutrients entering the pool, (for example constructing the edges to prevent surface run-off water entering the pool).
The higher plants (lilies etc.) in the pool will compete for what nutrients are left in the water and deprive algae and duckweeds.
I did some simple heat calculations based on our intermittent summer weather and came to the conclusion that insulating the lower part of the pool was beneficial to keeping the temperature "swimmable" - especially for smaller pools. I usually swim in the pool most days. I have even built a sauna to bring the pool alive in the winter!
This is me breaking the ice and surviving my first winter swim.
Hi Julia,
that is a very good point you bring up. The pool edges have to be constructed to prevent nutrient rich surface run-off from the surroundings entering the pool.
Hi Ivan,
your thoughts are very welcome and informative and tie in with the option I gave a the beginning. Building two separate pools, one for plants to condition the water and one for swimming. They are interconnected only through "snakeproof" pipework.
Hi Alexa,
ducks are the angels of doom for a Natural Swimming Pool!...OK well I'm over dramatising.
Here are the reasons:
1) They pull up the plants in and round the pool. The plants are needed to condition the water in a Natural Swimming Pool.
2) They stir up sediments, introducing nutrients into the water. (nutrients leads to algae)
3) Their poo introduces lots more nutrients.
4) They are a health hazard albeit not a dangerous one. Swimmer's ich - cercarial dermatitis. Flatworm parasites that use both freshwater snails and waterfowl as hosts in their parasitic life cycles. On leaving the snail, they mistake swimmers for ducks and die as soon as they enter our skin. But it can cause an irritating itch.
A quack can send me into a Pavlovian response, I jump up, run out the door and shoo the wild ducks off the pools.
Hi Devon,
thank you for asking such good questions.
by "messing it up" I mean the following:
1) some fish will uproot plants. Plants are needed to condition the water in a Natural Swimming Pool.
2) fish stir up sediments, introducing nutrients contained within them into the water.
3) fish need feeding. This is bringing more and more nutrients into the closed system of the pool.
Nutrients lead to stronger plant growth. The plants most able to react to an influx of nutrients are algae. Single celled suspended algae make the water green and opaque. Filamentous algae form "blankets" over the surface.
In a large body of water, like a lake, with natural levels of fish stocks, the biology can cope with the increased nutrients so fish and swimming can coexist. In a smaller body of water, more of a swimming pool size, fish are not good swimming partners.
Devon Olsen wrote:thank you for the response David, yes i do plan to have a deep part of the pond, for fish and for water retention to help slow evaporation, this being the lowest portion of the pond would hopefully hold at least a few feet of water during even the toughest drought as well as provide a place for the fish to retreat during our cold winters... or at least thats the idea anyway
but i also want the largest section fo the pond, the uphill and shallowest end of the pond to be mostly shallow water with plenty of darker stones to help the water gather heat in the day time, do you think this will do what i hope to accomplish along the lines of keeping it warm enough for swimming or will the cool water coming up from the depths be a problem and prevent temps from warming up?
and contrary to sepp's recommendation to run the pond parellel to primary winds i am running my along with the suns path to maximize heat capture and minimize evaporation through the desicating winds of the area, mainly because that seems to be the best placement more than anything though...
personally i like swimming with fishies and have not found lake water or stream water to be too nasty or anything by any means, but thats my personal opinion, have you tried to build pools that incorporate fish and if so what have been your experiences with that? did you have "clean" sand at teh bottom or was it just local soil or pond scum built up over time?
brenda i looked at your blog, very pretty but now i have more questions lol, one of which i believe ill have to start a new thread for another day...
but do you pump water out of nessecity or just to supplement things, i just kinda looked at pics and didnt read through much so im not sure what the size of your pond is?
also, i hope this doesnt come across as offensive but the water seemed a touch browner than i would like in mine, this could be cus of when the pics were taken in accordance to digging and perhaps you arent yet done planting the edges? but does the water clear up at certain time of year as compared to other times of year or is always a slight touch of brown? (mind you i grew up swimming in the muddy virgin river in southern ut so murky water doesnt stop me from taking a dip lol)
Hi Devon,
cold water from depths won't naturally rise as it is more dense than warm water. The water is said to be stratified. So the sun will warm the upper layer of water, unaffected by the lower layers.
I also love swimming with fish. I swim in the sea, in rivers, in lakes, almost anywhere. I would love to have fish in my pools but they will mess it up, due to the increased level of nutrients they introduce.
Hi Julia,
you can have you Natural Swimming Pool anywhere. Some are even built right up to the back door.
Have a look at Bill's pool. He came on one of my courses and went off to build this in his garden.
You could build it next to your existing rain garden but in order to minimise the possibility of nutrients being introduced into the pool water (nutrients=algae) it would best best not to have them hydraulically connected. However this can easily be achieved without seeing the pool edge by covering the join with gravel.
Hi Sandy,
the most costly item for a self built Natural Swimming Pool is the pool liner. You need to measure it up and get a quote. (here in the UK it's around £5 per square meter so I'm guessing around $1 per square foot).
I can't really advise on the snake issue. A conventional chlorinated outdoor pool will carry a similar risk so talk to a local pool installer to see how they deal with snakes. Better still get advice from a local ecologist. It maybe the case that any pool, Natural Swimming Pool or conventional pool, may not be appropriate to your area.
Many hundreds of Natural Swimming Pools have be made in Austria and Switzerland with synthetic liners. They endure pretty cold winters perfectly well.
No animals should be bought and introduced into a Natural Swimming Pool. The only animals in the pool are ones that have made there own way in there so they will be adapted to the pool conditions. The same rule of thumb should apply to the plants. Species native to the locality are going to be the best survivors and be most beneficial the local ecology.
There is no need to circulate the water during the winter in a Natural Swimming Pool. The native animals will look after themselves under the ice cap.
Morana Revel wrote:I am also faced with limited space.
I have 5 acres total about 3 times as long as it is wide. I know that there is a an underground stream of some sort that runs thru my property.
The problem is that where the water is closest to the surface is also on the same line as the 2 mobile homes that are on the property.
So there is the fence, several hundred feet and then a mobile home. The mobile home is set up as storage, so there would be no problem with run off or contamination. But the area is just very narrow and would not support mulitple ponds
Hi Morana,
I have built a very small pool to show how they can work with very limited space.
Devon Olsen wrote:from my limited understanding of the guest's techniques, the idea is to build two seperate ponds, one for swimming and one for critters, or at least seperate areas for swimming and critters
there is also shallower water in swimming areas to help make for warmer water
from my understanding there is also a fair bit of pumps and pipes involved in the process
but what if you lack the space for two sperate ponds or dont mind swimming where you might see fish if you donned a pair of goggles?
also what if you are not wanting to use pumps and such
how do you ensure clean, clear water and good water circulation?
also i have heard of getting some kind of bacteria for fish tanks to introduce to the sand so that the sand will pretty much eat whatever fish poo that comes into contact with it, if youve heard of this, what are your thoughts on using them in a swimming environment?
i really enjoyed the concepts in your youtube vids, and cant wait to take your ideas and apply them to my situation
for instance, i plan to incorporate a skinny point in the pond (only 6-8 ft wide) in between the main swimming part and the fish part, but i do not personally want any kind of physical barrier to stop anything that swims from going one direction or another
i also plan to make the skinny point the beggining of the main drop off from swimming/wading depth with a max of 10ft to drop down to 20-30ft
i almost wrote down the detailed description of my pond design plans, but i couldnt describe it without getting what seemed to me to be confusing so that all you get for now:)
Hi Devon,
I have built my pools with the planted zone and swimming zone incorporated within the single body of water. I enjoy swimming with any animals that venture into the swimming zone.
I suggested building separate planted and swimming pools only if there was a fear of animals (snakes) in the swimming zone.
If you don't want to pump the water then the pool will have to be large (around 1000 square feet) to rely on natural convection currents.
Fish are not recommended for Natural Swimming Pools. They stir up the sediments and introduce nutrients into the water. Nutrients (usually phosphorous is the limiting nutrient) lead to algae formation.
I wouldn't introduce any "special" bacteria. All the beneficial bacteria the pool needs will find its own way in there.
It sounds like you are planning a very deep pool that may be good for fish but as the water will be cold down there it will not good for safe swimming.
Hi Johan,
The low temperatures are not a problem in terms of the ecology of the pool. However, the rising winter groundwater will pose problems if the liner is laid directly on the pool floor. The ground water will make it "balloon" up. The liner will have to be trapped within an outer layer of concrete or stone flags on the floor and an external wall within the swimming zone.
Hello everyone.
I’ve only just emerged from spending the last five years digging holes in my garden and making films about digging holes. While I’ve been down there, I’ve failed to keep up with the dizzying social media phenomena so forgive me if I’m a little clunky on here. I have been kindly invited by Paul to talk about my hole digging adventures contained within my DVD, “Natural Swimming Pools – A Guide to Designing and Building Your Own” published by Permanent Publications.
A Natural Swimming Pool, or Organic Pool (I prefer “Organic Pool” because it is easier to say and a more accurate description) is a swimming pool that employs plants and animals to create hygienic water without the use of any nasty chemical disinfectants. It’s a beautiful example of how being permaculture minded, doesn’t mean you have to miss out on luxury.
The DVD is a self-build guide and a documentary of the pool building process. First, I show to make a small Organic Pool, step by step. Then, I show how to make a larger pool and how sometimes pool making can go wrong. The idea being, if you can see my mistakes, you can neatly side step all of that wasted effort. I’m happy to answer any questions you may have.
If a pool is filled with water containing lots of nutrients then problems with algae can occur.
Rainwater is usually the best quality water available as is contains very few nutrients. However, a lot of pools are filled with tap water and are usually fine. It just depends on the quality of water you have available. If it is drawn from ground water that contains leachates from agricultural fertilizers then that is a recipe for algae. (Most ponds in our countryside are polluted like this nowadays). If the water is drawn from a deep well then that may well be fine - it's all down to the water quality.
Modern DVD players will take NTSC and PAL. This DVD has been produced in PAL format and the language English, because that's all I speak. I have sold quite a few of these DVDs to the US and there has not been a problem playing the DVD.
I will also check with situation the publishers regarding the Amazon listing information.
Has there been an example of this occurring in a Natural Swimming Pool? Many thousands of Natural Swimming Pools have been created and there have been no reported health issues.
Hi Lisa,
thank you for the welcome to Permies - I like it here.
I build my pools with pond liners. It is a bitter pill to swallow, but I figure building a pond, is probably one of the better uses of plastic. A pond made with a liner is not fed from the ground water so the ground water level is not a determining factor. (A pond or Natural Swimming Pool is best filled with rainwater.) If such a pool was allowed to run dry, the liner plastic would photodegrade in the sunlight. Also a clay lined pool would crack - although I have attempted, I have so far failed to line a pool with natural materials.
Hi Ivan,
A Natural Swimming Pool can be constructed with two separate pools, one for the plants and animals, and one for swimming. Their only interconnection would be via pipework. The swimming area could look similar to a conventional pool. So the issue is really, if is safe to swim in a conventional chlorinated outdoor pool swimming in your area then a Natural Swimming Pool should be just as safe.
1) Yes, you could have a pool without any gizmos but it would have to be large enough to allow natural convection currents to provide all the circulation (around 1000 square feet). The pool also needs to be carefully shaped to aid the convection.
2) Everyone is very receptive! The only trouble with neighbours we have, is they are often popping round with their children for a swim.
Hi Jodi, thank you for the welcome. I would suggest studying the local environment. If there are ponds or lakes with plenty of biodiversity then a Natural Swimming Pool should work fine.
Hi Kim, no I haven't made a pool in a hot climate like Texas. I know they have been made in Australia with (probably) a similar climate so it should be possible. Unless the pool is really big, you may have issues with "dumping" the heat from the house into the pool water. If the pool gets too hot, that can lead to problems.
Hi Dave, there are several ways to reduce evaporation. Reduce the surface area to volume ratio of the pool. Reduce the air flow over the water i.e keep the wind off with hedges and fences. Have a lot of surface covering plants with floating leaves - like water lilies. Keep the temperature of the water as low as possible by having the pool a greater depth. Also careful care of pool edge construction to make sure there are no capillary bridges "sucking" water out of the pool into the dry surroundings.
Air lift pumps are ideally suited to pools that require a large amount of water to be circulated at low pressure using very little energy. They have been used for years in fish farming and dredging. The application to Natural Swimming Pools is a novel but natural place for them. They are no good for powering fountains, but hey... what are we trying to achieve? A pool for swimming or the water gardens of Palais de Versailles?