Northeast Pool and Spa Show: Where’s the ECO?

The 2015 Northeast Pool and Spa Show is coming up this January. It is a big deal. All the players are there. It is the BIG event for pool people on the East Coast. They have hundreds of classes, seminars and presentations.

And not one on Natural Pools…

Just in case you forgot how beautiful a natural swimming pool is.

Just in case you forgot how beautiful a natural swimming pool is.

As a natural pool builder I just shake my head in amazement. Do we even share the same planet?

A natural pool uses no chemicals, has a tiny pump if any, and is the most wonderful magical swimming experience you can imagine.

Toxic pools use massive amounts of chemicals that take a lot of energy to make, they have energy guzzling pumps and lots of PVC materials, and is like swimming in a giant cup of noxious chemicals.

How in the world is it possible the pool pros aren’t pushing natural pools as the best swimming experience? Apart from the swimming experience, the two paragraphs above explain very clearly why the pool industry is not pushing Natural Pools. With Natural Pools there isn’t anything to sell! You build it and walk away. With a toxic pool you build it and guarantee a lifetime of product sales in chemicals, pumps, filters etc.

This image shows how much energy toxic pools consume, and this does not include all the energy it takes to make the chemicals. A natural pool consumes nothing.

This image shows how much energy toxic pools consume, and this does not include all the energy it takes to make the chemicals. A natural pool consumes nothing, or at the very most it uses a small pump (about 100W).

Natural Pools have to come through customer demand, not industry supply. The pool industry is just fine with what they are selling and don’t want to stop selling it. But if customers stop buying things change.

Demand a natural pool. If you have a toxic pool, convert it to a natural one. Lets get right of toxic pools and increase natural aquatic ecosystems that are good for humans, plants, and the planet.

Converting a toxic pool to a natural pool is even more ecological. Not only do you create a natural swimming pool using less energy but you also remove a toxic one.

Joining Professional Organizations for Landscapers

Eco Brooklyn is an NY ecological landscaping company currently working on a project to build a natural swimming pool (read more here.) Natural pools are a new service that Eco Brooklyn is adding to our long list of amenities.

In an attempt to gain publicity for Eco Brooklyn’s green contracting services, we considered joining a few professional organizations. Here is a list of those organizations and the membership fees our company would apply for:

  • American Society of Landscape Architects– Affiliate Member (individual): $322 or Corporate Member (company): $1,950
  • Association of Professional Landscape Designers– Industry partner: $400 or Professional member: $240
  • Genesis 3 Design Group– Silver Sponsor (cheapest option): $3,000
  • Association of Pool and Spa Professionals- Builder/Installer membership: $575

The benefits of joining these organizations include having your company’s name posted on their website, being able to tout your membership on your website or to customers, and sometimes access to professional practice networks.

In the end, Eco Brooklyn decided these benefits weren’t for us. We already have enough business  in our multidisciplinary field – a wide range of interconnected services from gut renovations, green roofs, gardening, ponds/waterfalls, and more.

Our jobs almost never fall only under one category – say landscaping – because green building is such an interconnected process, so we decided that advertising ourselves in any one specialty isn’t a thorough representation of the business we do.

However, this is a personal choice so if you are a green contractor, waterscaper, landscaper, or salvage and renovation company interested in pursuing such a membership, the above organizations are the ones we recommend.

natural pool contractin

Eco Brooklyn's natural swimming pool. A natural pool has two zones, the swimming area (center) and the regeneration area surrounding it, which will be filled with gravel and plants to clean the water.

 

green contracting nyc

Here is an example of a completed natural swimming pool

Natural Mosquito Repellent

Brooklyn’s beautiful summer days coax us outdoors to converse and lounge in our parks, backyards, and porches. In the heat of the summer, water features are a welcome cooling sight and draw the abundance of people looking to maximize their free time. However, these same water features are also home to pesky mosquitoes, diminishing the quality of our outdoor experiences.

At Eco Brooklyn, we are developing natural methods of mosquito control. These methods aim to diminish the mosquito’s presence while maintaining the balance of our fragile local ecosystems. We have a mosquito-repellant service with several components and options, which we make available to the community in an attempt to combat the mosquito problem on a larger scale.

Our service uses three main tools to reduce mosquitoes:

1. Landscaping Mosquito repellent plants – yards, pots and living walls.

2. Water features for mosquito predators – Fish and Dragonfly ponds.

3. Natural oils applied to the skin and garden area surfaces.

New York and Brooklyn were originally full of marshes, rivers and wetlands, which most probably had lots of mosquitoes. The difference now is that those areas are gone, and so are all the creatures and plants that kept mosquitoes at bay.

Now, with little left but clogged gutters and putrid waterways like the Gowanus Canal, there are few predators to the mosquito. Add to that the introduction of non-native mosquitoes from Asia that have even less predators here, and you have a real mosquito heaven (for the mosquito that is. Not for us humans).

Mosquitoes are a problem worldwide.  A wide variety of defenses have been put into effect to reduce the impact of the insect, some with more success than others.

Many of these methods have negative affects on the surrounding environment and may in fact be simultaneously attacking the mosquito’s natural predators. Broad-spectrum insecticides such as the organic pesticide Pyrethrum may kill mosquitoes and other insect pests, but they also kill beneficial pest-controlling insects such as ladybugs and lacewings.

Any attempt to reduce mosquito numbers must be founded in the natural lifecycle of the mosquito itself. The mosquito lays its eggs in standing water and hatches as larva before changing into pupae, then emerging and taking flight. Any standing water greater than a bottle cap’s full can serve as a mosquito-breeding site.

As such it is very important to eliminate small containers that have the potential to fill with rainfall and remain inactive. The elimination of all rainwater collection sites, however, is far from necessary. Slightly larger ponds can be effective methods of mosquito control by acting as habitats for the mosquito’s natural predators.

Some of the mosquito’s natural predators are dragonflies, damselflies, bats, and numerous fish species. While bats do consume mosquitoes, they are at most 5% of their diet. Extensive bat preservation policies, while beneficial to the bat, may not in fact greatly diminish the inhabiting mosquito population. Many fish will consume mosquitoes, but some are better adapted to the task than others.

Fish

The highly touted mosquitofish Gambusia affinis can consume 42-167% of its body weight in mosquitoes per day.  Its mouth is faced upwards towards the sky, allowing for more efficient consumption of mosquito larvae. It can tolerate various temperature changes in the water, salinity, decreased food supply, and organic pollutants and is compatible with goldfish, koi, and karp.

A nonnative species, it was first introduced to New York’s waters as a biological control for mosquitoes. However, mosquitofish were found to be ill-adapted to the cooler waters. Most importantly, it is not compatible with native species and very few instances of coexistence exist.

As such EcoBrooklyn does not recommend the introduction of mosquitofish into existing garden ponds. If your brownstone garden already includes a fish pond, we recommend finding a hardy native fish species that can reproduce in the local climate, such as the fathead minnow.

Dragonflies and Damselflies

Fish are not the only mosquito predator reliant on a pond source. Dragonflies and damselflies lay their eggs in foliage above or below the waterline of a pond. They then hatch as aquatic predators, consuming mosquito larva to feed and grow.

Depending on the species, this stage of life takes 1-2 months to 5 years. The larva then climb out of the pond via a plant stalk or rock and seek protection in nearby foliage before taking flight and attacking mosquito adults.

The life cycle of dragonflies and damselflies therefore shadows that of the mosquito, but the predator-prey relationship remains the same effectively controlling mosquito populations. Adult dragonflies and damselflies return to water features to feed and sun themselves, and eventually lay eggs in the pond.

Eco Brooklyn offers a dragonfly pond building service as a component of its mosquito solutions. Dragonfly ponds are a beautiful addition to a brownstone garden, and the insects provide welcome entertainment on a summer’s eve.

15% of North America’s 307 dragonfly species are in danger of extinction, and a new dragonfly habitat can help the graceful insects to reestablish themselves while also providing a welcome solution to the mosquito problem!

A dragonfly pond by Carole A. Brown

A dragonfly pond should vary in depth, with a segment around 2 ft in depth and flat rocks such as slate on the shallow side. Water plants should be included in the deeper parts of the pond to serve as nurseries, with perching sedges and rushes on the side for adults. It is also recommended that a small wildflower grassland be planted on the side of the pond.

The pond should include erect and submerged plants to allow for dragonflies and damselflies at all stages of the life cycle. A small pump can be included to keep the water clean and oxygenated, although this is not necessary for larger ponds. While the best dragonfly ponds are 20 feet wide, this width is not practical for a NY lot nor is it necessary to maintaining a healthy population.

In fact, adapted whiskey barrels, fountain basins, and earthen or plastic lined ponds can all provide welcome habitats as long as there are sloped sides and varying depths. The dragonfly larvae like to hide in the depths of the water to escape predation, but sufficient plant cover may substitute for that in the case of shallower ponds.

A simple stake in the pond can substitute for erect perching plants. It is very important that the pond be 70% in the sun and that no fish are added to the water.

Fish consume dragonfly larva as well as mosquito larva and are therefore incompatible, unless we design the pond to have two sections so there are safe places for the larvae to escape.

Once the pond is built we jumpstart it with a few spadefulls of soil from a nearby pond with a known dragonfly population.

The following plants work well in a dragonfly pond:

Deepwater -submerged plants

Curly pondweed – Potomogeton crispus

Water Starwort – Callitriche spp

Hornwort – Ceratophyllum demersum

Spiked Water Milfoil – Myrophyllum spicatum

Deeper water Floating Plants

Stiff-leaved Water Crowfoot – Rannunculus circinatus

Frogbit – Hydrocharis morus-ranae

Broad-leaved pondweed – Potomegetum natans

Amphibious Bistort – Polygonum amphibium

Yellow Waterlily – Nurphar lutea

Fringed Waterlily – Nymphoides pelatata

Shallow water emergent plants

Flowering Rush – Butomus umbellatus

Water Horsetail – Equisetum fluviatile

Bur-reed – Sparganium erectum

Water Plantain – Alisma plantago-aquatica

Common Spike Rush – Eleocharis palustris

Bog Bean  – Menyanthes trifoliate

Plants

EcoBrooklyn also installs plants as  a direct means of mosquito control. We offer several plant-based services:

-vertical frames planted with mosquito repellant plants, to be hung on the walls of porches, balconies, and other outdoor activity areas. The frames are made of cedar or pine as both of these woods repel mosquitoes.

-plant troughs filled with mosquito repellant plants, placed near outdoor activity areas

-herbal oil concoctions designed to specifically repel mosquitoes; these can be applied directly to the skin or sprayed on the surfaces of an outdoor activity area

-dried mosquito-repellant plants placed into sachets to be hung in desired locations

Below we have organized known mosquito repellant plants into two categories: native and nonnative species. Edible plants are subcategorized. We work with clients to offer aesthetically pleasing plant combinations.




Once planted, it is advised that plants be brushed before engaging in outdoor activities in order to release some of the scent. The compounds citronellal, geraniol, geranial, and pulegone are all known to repel mosquitoes. Plants containing these compounds are the most effective.

It is important to note that the plants themselves will not repel mosquitoes, it is the oil within their leaves that acts as a repellent. This is why brushing the leaves (resulting in small breaks) helps to repel mosquitoes. Our plant troughs and vertical installations  are meant to be a reliable supplier of leaves for your own herbal concoctions while also aesthetically ameliorating your home.

We highly recommend troughs consisting of edible mosquito repellent plants, which provide the additional ecosystem service of providing food.

Herbal solutions

While there are many variations of mosquito repellant liquids, they are made similarly.

The first method uses actual plant leaves from mosquito repellant plants. These are steeped in water, strained, and then the liquid is added to isopropyl alcohol.  Any combination of plants works well as well as using a single plant per batch.

The second method involves mixing 2 ½ teaspoons of any combination of essential oils (basil, cedarwood, cinnamon, citronella, juniper, lemon, myrrh, palmarosa, pine, rose geranium, rosemary) with 1 cup of 190-proof grain alcohol. These concoctions can be applied directly to the skin or used in a spray bottle. If applied to the skin, it may take some experimentation to determine what combination of oils works best with one’s body chemistry.

As described by the above overview, there are many natural means of combating the mosquito problem in Brooklyn. EcoBrooklyn is constantly improving its services through experimentation in the Green Show House and offers its solutions to the community.

These solutions aim to repel mosquitoes, add to the aesthetic value of Brooklyn brownstones, and support native species and the local ecosystem.

Eco Brooklyn is a Natural Pool Installer

For the past couple years we at Eco Brooklyn have invested a lot of time learning how to create natural ecosystems in the New York environment. Our work has paid off with the near completion of the gardens at the Eco Brooklyn show house.

Here is a sneak preview of our front yard pond and back yard natural swimming pool. With these two showcases we hope to provide natural swimming pool installation and pond services for the New York area.

We have been doing a lot of building with salvaged materials and low energy design in an attempt to reduce the footprint on the world. We gradually moved into the gardens of the brownstones because as a green builder it all becomes connected.

The gray water and compost from the house goes into the gardens. The rain from the green roof passes down the living walls and into the dry wells in the yards. This kind of design reduces the footprint on the world but also very directly on NYC. If everyone built like this we would not have sewage running into our waterways and we would be able to swim in them.

Keep in mind the pictures below are taken in a “normal” Brooklyn brownstone front and back yard….add a little green building knowledge, some hard work, inspiration from Manahatta and Presto! you get this:

Show House back yard pool

Back Yard pool

Back yard pool. Honestly, it is more of a dunking pond but it’s a pool by NY standards!

Front Yard pond

Natural Pools

We at EcoBrooklyn engage in a number of exciting green building projects and experiments throughout the year, but with the hot months ahead at the top of our list is the natural pool for the show house and with its completion so close we can almost feel the cool, energetic, life infused water on our toes.

A “Natural pool” is more about incorporating nature into the design and functions of the pool, harnessing natural processes to maintain quality, swimable water and blurring the line between built and naturally occurring.

A healthy body of fresh water has a number of checks and balances that keep it in balance. A Natural Pool simply recreates these elements. Nature does the rest.

A Natural Pool has the swimming area and then another area called the regeneration zone. This zone contains plants and, most importantly, surface area usually in the form of gravel that microbes can live on.

The plants and microbes compete with algae for food and since you pack it with surface area the microbes beat out the algae. In essence you create an environment where food (leaves, soil, bugs, and other organic matter) is scarce, so what food there is becomes eaten by plants and microbes instead of algae.

The process is fairly flexible and can be as simple or complex as you like as long as you have a few basic elements:

-No chemical fertilizers/ pesticides used adjacent to the site

-Natural filtration system

-A variety of different plants, surface area and microbes to promote a balanced ecosystem

The beauty of natural pools

The primary appeal of a natural pool is the absence of the typical cocktail of harsh chemicals designed to kill pretty much everything in the water, except the swimmer more or less.

The second attraction is the positive ecological effect; this is something you can build with salvaged and recycled materials while helping to reinstate local/native ecosystems.

As with most things green there is a degree of time and thought investment not usually associated with the typical energy sapping, chlorinated eyesore.

there’s no competition really

 

Maintenance is still simpler and less expensive, but one needs to learn and follow a set of steps and rules, which as one grows with the pool these steps become second nature, or perhaps first nature…

Thankfully there are always pioneers braving new frontiers and providing the general populace with valuable resources and tools to implement in their own projects.  The Europeans especially have been at the forefront of the natural pools race for over a decade now. They have built massive public natural swimming pools that cater to thousands of people with great success.

beautiful design

wide range of options

Below is a list of websites and organizations specifically geared towards natural pool construction; they provide excellent technical suggestions for all types of designs and constraints as well as helpful trouble shooting for any problems that may arise.  Also they can provide you with competent local green contractors and builders in your area familiar with this sort of construction.

Eco Brooklyn hopes to become a leading natural pool installer in the New York area. We feel this is an excellent option since it adds so much to a garden, both for humans but for native wildlife.
http://www.motherearthnews.com/Do-It-Yourself/2002-08-01/Natural-Swimming-Pool.aspx
http://www.biotop-gmbh.at/

http://www.ibnature.com/

http://www.totalhabitat.com/p&p.html

http://www.clear-water-revival.com/

 

-Michael DiCarlo

How Our Soul Connects to the Earth

I spent the day in the Eco Brooklyn garden with seven interns today hauling salvaged blue stone around and working on the natural swimming pool. Typically we are working around the pool so they have their shoes off.

Adding the final touches to the natural swimming pool

But today I had them wear shoes to protect them from the heavy stones they were hauling.

I know the garden very well and can navigate the many native plants and stones with my eyes closed. For the most part the interns have been pretty good at where they put their bare feet as well, even if it is more to protect their virgin feet than to protect the garden.

But today they were like a herd of elephants. Carried away with their work, they forgot what was beneath their shoes. And asking them to be more aware didn’t lessen the damage.

Considering they were so intelligent in other areas I expected a much higher level of awareness from them and I found myself getting frustrated. And it wasn’t like they didn’t care or had physical disabilities. These college level athletes were mortified when I pointed out the damage their feet were doing.

It made me think about intelligence in general and how different societies value different things. In mainstream North America intelligence is measured in college test exams. In the Jungles of the Amazon intelligence is measured in whether you step on a snake or not.

But more importantly I had this profound realization that these seven intelligent college grads had spent the vast majority of their lives walking on dead materials – concrete, tile, car carpet, varnished wood – with shoes. They were completely illiterate when it comes to talking to the alive earth with their feet.

99% of the time they don’t need to be aware of where they are stepping. They have to navigate dead objects like getting out of a car, running on a track or walking up stairs but these things are all standardized – hard, flat, lifeless – so the process requires minimal awareness. The worst that can happen is they step in dog crap and never do they worry about killing anything.

The Eco Brooklyn back yard, however, is full of life and far from standard. There are little piles of stones to be toppled, plants of all sizes to be trampled, snails and bugs to be crushed, and all sorts of other life forms like mushrooms, moss, lichen, and berries that a Nike shoe easily kills.

Bees from the roof drinking water from moss in the Eco Brooklyn show house pond.

This lack of connection between our feet and the soil is powerful. I saw these kids with great intentions slowly trampling their surroundings and it brought up in me much more emotions than what was at hand. It reminded me of the many times I see environmental destruction due to a lack of awareness of and connection with the earth.

People are good. But disconnect them from their surroundings and they become killer monkeys.

This was a real learning experience for me as I work with them as a mentor. I have extra wide feet because I spent most of my summers as a boy barefoot. I remember crying from the pain of trying to put my feet into shoes at the end of summer for school. Maybe this gives me good connection between my feet and the soil. It isn’t much compared with so many people on this planet who live closely with nature but in NYC’s concrete jungle I’m an exception.

It drove home in me that more important than understanding the ecology of a natural pool or eco garden is having the awareness of where we step, both physically and metaphorically. An awareness of ourselves as we move on this planet and impact other life forms is the height of environmentalism. This has been a valuable lessen for me both in my own life and in my teaching.

International Center of Photography Pics

Last week students from the International Center of Photography came by to photograph the show house green roof and back garden. Here is what they came up with.

Our Favorite:

RobertSJohnson_EcoGarden

As green roof installers we are particularly in love with the green roof on the show house. It is where we do a lot of experimentation to see what works on NY green roof installations.

 

As New York green roof installers we are particularly interested in creating roof top sanctuaries not only for humans but for native animals. This birds nest is part of that process of turning a bleak roof into a home.

New York Natural Swimming Pool

From the green roof you can see the back garden which is under construction. It has all native plants arranged in a native hardscape. It also has a natural swimming pool that will be cleaned by plants and stones.

 Eco Brooklyn NY green roof service is doing well and we are now expanding to provide natural swimming pool construction services for New York residents with small back yards. We feel this is a great thing that adds to the ecosystem and quality of life. Our first one is being built in the Eco Brooklyn green show house. We are making all the mistakes we can to perfect the process.

The natural pool is common in Europe but Americans are still stuck on keeping nature and humans apart, and this applies to chlorinated pools as much as it does to other things. But as we learn that nature (bugs, microbes, dirt) actually can help keep us healthy it makes a lot of sense to swim in a natural swimming pool.

With time we hope more and more people will see that chlorinated pools are actually lass sanitary that natural swimming pools due to the connections between chlorine and health issues like cancer, rashes and breathing disorders.

 

Joining Professional Organizations for Landscapers

Eco Brooklyn is an NY ecological landscaping company currently working on a project to build a natural swimming pool (read more here.) Natural pools are a new service that Eco Brooklyn is adding to our long list of amenities.

In an attempt to gain publicity for Eco Brooklyn’s green contracting services, we considered joining a few professional organizations. Here is a list of those organizations and the membership fees our company would apply for:

  • American Society of Landscape Architects– Affiliate Member (individual): $322 or Corporate Member (company): $1,950
  • Association of Professional Landscape Designers– Industry partner: $400 or Professional member: $240
  • Genesis 3 Design Group– Silver Sponsor (cheapest option): $3,000
  • Association of Pool and Spa Professionals- Builder/Installer membership: $575

The benefits of joining these organizations include having your company’s name posted on their website, being able to tout your membership on your website or to customers, and sometimes access to professional practice networks.

In the end, Eco Brooklyn decided these benefits weren’t for us. We already have enough business  in our multidisciplinary field – a wide range of interconnected services from gut renovations, green roofs, gardening, ponds/waterfalls, and more.

Our jobs almost never fall only under one category – say landscaping – because green building is such an interconnected process, so we decided that advertising ourselves in any one specialty isn’t a thorough representation of the business we do.

However, this is a personal choice so if you are a green contractor, waterscaper, landscaper, or salvage and renovation company interested in pursuing such a membership, the above organizations are the ones we recommend.

natural pool contractin

Eco Brooklyn's natural swimming pool. A natural pool has two zones, the swimming area (center) and the regeneration area surrounding it, which will be filled with gravel and plants to clean the water.

 

green contracting nyc

Here is an example of a completed natural swimming pool

New York Natural Swimming Pool

Eco Brooklyn is building a natural swimming pool in its show house. Below is a good article that explains how to build one.

Whether you like to practice your dolphin dives or lounge away the day on a raft, swimming is one of summer’s perfect pleasures. With a minimum of materials (and without an arsenal of chemicals), you can build an idyllic water oasis right in your own back yard and thwart summertime’s sultry dog days.

By Douglas Buege and Vicky Uhland

While fairly common in Europe, natural swimming pools (like the one pictured above in an Austrian family’s back yard), are in their infancy in the United States. Ask an American swimming pool contractor to build a backyard pool and chances are they’ll roll out a long list of goods, including rebar, gunnite, fiberglass, chlorine and an energy-sapping filtration system. But in recent years, a few builders and a growing number of homeowners have learned how to build pools without relying on a mass of manufactured materials and chemical additives. They’ve found it’s possible to construct pools are more about learning from nature than selling supplies.

Natural swimming pools use gravel, stone and clay in place of concrete or fiberglass, and aquatic plants instead of harmful chemicals and complicated mechanical filtering systems. The plants enrich the pool with oxygen, support beneficial bacteria that consume debris and potentially harmful organisms, and give habitat to frogs, dragonflies and other water life. You only fill the pool once, and the result is a beautiful, ecologically diverse system that is relatively inexpensive to construct. (A natural pool can be constructed for as little as $2,000 if you do it yourself, while conventional pools can cost tens of thousands of dollars.) Natural swimming pools require no harmful chemicals, are fairly low-tech, and, once established, call for only a modicum of management.

DIG IT

The cheapest and most ecologically sound way to build a swimming pool is simply to hollow a hole in the ground. You can make your pool as shallow or as deep as you want, but the key is to make sure the sides slope, otherwise the soil will cave in. The ratio should be a 1-foot vertical drop for every 3 horizontal feet. “It’s not a bathtub effect, but more like a soup bowl,” says Tom Zingaro, partner with Denver-based Blue Lotus Designs, a pool and pond architecture company. One of the main reasons traditional swimming pools are constructed with a steel framework is to ensure the walls stay vertical and perpendicular to the bottom surface of the pool. Construct a pool with sloping sides and you’ll eliminate the need for any steel reinforcement.

ZONING

Reserving at least 50 percent of your pool’s surface area for shallow plants, either at one end or in a ring around the sides, eliminates the need for chlorine and expensive filters and pumps.

 You’ll want to separate the swimming area of your pool and the filtration area, or plant zone (see the illustration on Page 31). A rim within an inch of the water’s surface keeps plants in their place but allows water from the swimming area to move to the plant zone for filtering. As water passes through the fibrous root structure of the plants, bacteria concentrated on the plants’ roots act as a biological filter, removing contaminants and excess nutrients in the water. In concert, decomposer organisms, also found in the plants’ root zones, consume the bacteria, effectively eliminating waste buildup underwater.

Inside the plant zone, the water should get steadily deeper, reaching a maximum depth of 18 inches near the swimming zone. The outermost 6 inches of the plant zone will be 2 to 3 inches deep, providing a home for taller aquatic plants. Submergent and floating vegetation occupy the deeper area.

Besides cleaning the water and making your pool beautiful to behold, the shallow plant zone warms the water quickly and provides habitat for frogs and many invertebrates. Theyll appreciate the shallow waters for breeding grounds and repay the favor by eating mosquito larvae.

NATURAL FILTRATION

For the plants’ roots to cleanse the water, the water needs to circulate continuously. You may also need to aerate your pool’s water so that gaseous oxygen meets water organisms’ biological oxygen demand (BOD). (Without adequate oxygen, your pool could become stagnant, harboring odoriferous anaerobic bacteria.)

Water can be channeled from your pump into your plant zone through the use of PVC tubes. Zingaro recommends using flexible PVC in cold climates. In any climate, bury the tubing in the soil about 18 inches. Underwater aeration, which uses less energy than constructed waterfalls and circulates water more effectively, involves diffusing air at the pool’s bottom. You can build your own aerator, using an air compressor (1/4 horsepower for a pool smaller than an acre) and high-strength tubing that connects to a diffuser. The diffuser (see Sources, Page xx), which bubbles air through the water, rests in the deepest part of the pool where swimmers are not likely to damage it. Connect a brass manifold to the compressor to regulate the air pumped into the pool. Don Schooner at Inspired By Nature, an Ohio-based pond and lake restoration company, suggests aerating the pool four to eight hours a day: in the morning, when oxygen demand is greatest, and again in the evening. Place your aerator, pump and skimmer in a plastic container such as a bucket or large plant container and put a steel mesh filter mat over the top to keep debris out of your equipment. Expect to pay around $1000 to $1200 for a high quality underwater aeration system.

Some folks employ skimmers in their pools, hooked up to an additional small pump, to suck off floating undesirables. While these devices are not essential, you might want to consider purchasing one if leaves or seeds from nearby trees and shrubs often litter your pool. The skimmer removes detritus that would otherwise sink and contribute to algae growth.

Installing pumps and compressors can be a tricky business because you’re running electrical devices near or in water. You’ll want to connect electrical hardware to your home power supply through buried conduit. Do not run your power through an extension cord. Hire a skilled electrician who will ensure the safety of the system.

SEALING THE POOL

Once you’ve dug the hole for the swimming pool and the plant zone, you have a couple of options, depending on your soil conditions, to ensure the pool holds water: You can apply a layer of bentonite clay to seal the soil, or lay a synthetic liner. Bentonite is usually the cheaper option, averaging 35 cents per square foot. Liners can cost 25 cents to $1 per square foot, depending on their composition and weight.

Bentonite works as a glue, bonding with the soil particles and preventing pool water from seeping into the ground. Some soils may contain enough clay that simply compacting the pond bottom will enable it to hold water. Talk to local pond builders to find out for sure. But beware: bentonite doesn’t bond well with sandy soil. Particularly sandy soil can require up to 12 pounds of bentonite per square foot, as opposed to 6 pounds in clay-rich soil. Bentonite can also be troublesome when the surrounding soil is very dry. In arid climates, Zingaro recommends that bentonite be applied beneath a plastic liner that has a woven material next to the pool sides. This liner assures that the bentonite doesn’t shift. In more humid climates, bentonite can be applied directly to the soil. Before treating your pool with bentonite or any other clay powder, thoroughly compact the soil. You can do this with a lawn roller or a plate compactor. Then, making sure you’re wearing a mask, spread a 2- to 3- inch layer of bentonite powder along the pool sides and bottom. Pack it down with a tractor or plate compactor. Then apply another foot of good-quality topsoil and compact that.

If you choose a liner, choose one made of ethylene propylene diene monomer (EPDM) rather than polyvinyl chloride (PVC). EPDM is a synthetic rubber twice as expensive as PVC, but it’s worth it. It has ultraviolet-ray protection and unlike PVC, isn’t brittle in cold weather. If your soil has a lot of rocks or roots, select a 45- or 60-millimeter-thick liner. You can use a 30-mil liner if your soil is very sandy and smooth, and if you and your guests aren’t the type to tear holes in a liner while frolicking in the pool. Before laying your liner, compact the soil and cover it with a layer of sand or an absorbent material such as old carpeting or newspaper. Newspaper is a good option; when wet, it bonds to the liner, providing extra protection if the liner develops a small hole.

After bentonite clay or a liner is installed, cover the bottom of the pool with 4 to 5 inches of gravel. The gravel provides a substrate for beneficial bacteria, which help biodegrade leaves or other natural materials that sink to the bottom of your pool. Make sure that the gravel you use is clean. Fill a spigoted 5-gallon bucket with some of the gravel you intend to use. Open the spigot and run water through the gravel. If the water comes out dirty, you need to clean the gravel (a taxing, water-wasteful process) or find another source. Expanded shell aggregates and other manufactured gravels are likely to be clean enough to use in your natural pool. In addition to lining the pool with gravel, many people opt to build cobblestone steps for access into and out of the pool. A cantilevered dock built out over the water also provides an easy way to get in and out of the pool and helps protect the pool’s sides from damage.

To finish the edges of your pool, run a plate compactor around the perimeter. While this will help with soil erosion, it’s not enough to ensure that dirt won’t fall into your pool. One option is to edge the perimeter with rocks, flagstone or wood planking. Better still, says Martin Mosko, principal architect with Boulder, Colorado-based landscaping company Marpa and Associates, is to plant right next to the edge and let the plants stabilize the perimeter.

Plants not only work to stabilize the soil, but create a natural setting for an old-fashioned swimming hole effect. Mosko says if you choose to use plants, instead of stone, it’s best that the water level be at least a foot below the edge of the pool so the perimeter plants don’t become waterlogged or choose plants that thrive in wet soils.

CONCRETE OPTIONS

If you prefer a more conventional pool shape, consider construction with concrete or rastra block, a material manufactured from concrete and recycled Styrofoam. Less eco-friendly than using gravel and stone, these systems can still save on chemical and energy usage by using plant-based filtration systems, rather than mechanical filters and chlorine, to clarify the pool water.

Pouring a concrete pool can be tricky. You have to have the right mix and the right density to prevent cracking. Because of the intricacies involved in concrete pouring, Zingaro advises against do-it-yourself concrete pool construction. If you’re experienced in concrete work, he offers the following tips: Use an 80/20 mix of Portland cement and sand, and cover the compacted soil with fiber mesh, a rubber liner, old carpeting or newspaper to provide a stable surface concrete can adhere to. After the concrete is poured, trowel on an 1/8- inch-thick coat of stucco to waterproof the pool, since concrete is porous.

An alternative to concrete is rastra block. These blocks are 10 feet long, 15 or 30 inches high, and 10 or 14 inches thick. Made of recycled Styrofoam and concrete, they weigh a fraction of what concrete blocks weigh; two people can easily set 10-foot sections into place. Kenton Knowles of Global Homes in Baldwin City, Kansas, built a 16-foot by 32-foot pool out of rastra for about $1,600 in materials.

To build a rastra block pool, excavate a hole just larger than the pool’s dimensions to allow for ample workspace. Most people choose to construct a pool 5 feet deep. For the bottom, either pour a concrete slab or cover the bottom with a rubber liner. Then line the bottom with gravel. Make sure to install a drain and backflow preventer. Lay one section of rastra block along the edges of the slab, securing the rastra to the pad with rebar.

Fill the rastra blocks’ cavities with concrete. As the concrete flows from block to block, the structure is tied together. An expanding foam sealant is used between courses and at all joints to hold the blocks in place. Knowles recommends waterproofing the blocks by troweling on two coats of stucco. Backfill the space between the sides of the pool and the rastra block with soil. You can finish the perimeter with stones laid from the top of the blocks out into the surrounding area, or you can grow plants to the edge of the blocks.

PREPARE FOR PLANTING

Once your pool is constructed, you’ll need to prepare the plant zone with 3 to 6 inches of soil. Choose your soil with care as soil can carry various contaminants. Avoid harvesting soil from areas where animal excrement is prevalent, such as in dog runs or from grazing areas. Also, select soil that’s free of organic matter that would rot underwater. If you wish, you can have a lab test soil samples for potentially pathogenic bacteria.

Once soil, gravel and hardware are in place, you can fill the pool. Disturb the soil as little as possible and let the pool rest for a week before installing plants. During this time, you can test your hardware to make sure it works.

SELECTING PLANTS

Be sure to choose plants suited to your climate. Your best bet is to obtain your plants from a native plant supplier. Check the phonebook and Internet for local sources. Home and garden centers also carry more aquatic plants now that backyard ponds are growing in popularity. End-of-the-season sales can save you big money. Several mail order nurseries also specialize in water garden plants (see Sources, Page XX).

Sedges (Carex species) and rushes (Scirpus spp.), both aquatic plants, make great emergent vegetation for your pool’s perimeter. You can also consider aquatic irises and short cattails (Typha angustifolia), though be sure to find varieties that don’t overcrowd other plants. Pickerel weed (Pontederia cordata), arrowroot (Sagittaria spp.) and water primroses (Ludwigia spp.) are all contenders for the shallowest areas of your pool. Be sure to include submergent plants such as Elodea and Ceratophyllum for their high oxygen output.

In water 6 to 18 inches deep, plant a mix of floating, submergent and emergent plants. Water lilies (Nymphaea spp.) adapt to any depth, so use them liberally. Floaters such as pondweeds (Potamegeton spp.) and duckweed (Lemna minor) drift freely on the surface, and quickly cover the surface of the plant zone.

Before you make plans to tromp off to the nearest country pond and gather up a truckload of greenery, wait! Before collecting a single plant from the wild, know the laws that protect wetlands and their plants. If you do collect, be careful to guarantee the health of the wetland by selecting only a few samples from larger populations. Consider rescuing plants from a threatened site. Perhaps a new corporate headquarter’s construction is going to destroy your favorite frog hollow. Contact the company to see if they’ll allow you to rescue the imperiled plants (and maybe an amphibian or two).

Once you’ve purchased your plants, you can plant them in the filled pool. Stick to a plan, grouping plants according to height and type. Place your plants into the soil, anchoring them with plenty of gravel.

ALGAE CONTROL

Pond owners have been battling algae– the mighty green menace — for eons. Algae compete with plants for nutrients and light, but spring algae blooms often decline as soon as water lilies and other plants emerge to shade the water. Maintaining a lower pH (5.5 to 6.5) by adding plants and eliminating phosphorous will promote plant growth and deter algae. The easiest remedy, and the least risky to your aquatic ecosystem, is to add more plants, which will outcompete the algae for nutrients. A second option is to monitor the pool for phosphorus. Fertilizers and urine are the two major sources of this nutrient, so make sure your pool is free of nutrient rich run-off and remind everyone to use the bathroom before swimming. You can also increase your aeration schedule to stimulate more biological activity.

If algae problems persist, adding small amounts of straw to the pool will help. For full details, visit the Institute of Arable Crops Research Web site atwww.iacr.bbsrc. ac.uk/pie. Go to the Center for Aquatic Plant Management link and download “Control of Algae Using Straw.” For barley straw sources, go to www.ianr.unl.edu/pubs/wildlife/nf429.htm or www.naturalsolutionsetc.com.

Enzymes, bacteria, acids and other strange brews have been offered as magic bullets for obstinate algae. Introducing additives to your pool may be an interesting scientific experiment, but it won’t necessarily improve the pool you’ve invested plenty of time and money in. Beware of salesmen hawking their grand variety of miracle algae cure-alls. Remember: your pool is a dynamic, living ecosystem. Adding synthetic chemicals will probably not bring it back into balance.

MAINTENANCE

Removing plant litter in spring and fall will help maintain the long life of your natural pool. Keep your water level constant, and be prepared to add water as needed. Inexpensive test kits, available in garden centers, will allow you to monitor your pool’s nutrient levels, alerting you to problems.

In addition to maintaining the pool’s biological health, check the mechanical systems annually. Wipe diffusers with vinegar to remove deposits, check air hoses for cracks and obstructions, and examine all connections to the pumps. Given these precautions, your pool should provide you pleasure for years to come.