Articles from FH Wetland Systems
Following is a selection from articles written by Feidhlim Harty over the last number of years. The following versions of the articles exclude all photographs and may contain differences from the printed version due to editing by the publisher. They give a bit more information on wetlands and on related topics...
Constructed Wetland Systems for Municipal Wastewater Treatment - published in Construct Ireland Issue 4 Volume 2
Wastewater treatment can be both inexpensive and high quality when constructed wetlands are used as part of the overall approach. Both single houses and municipal systems are increasingly employing this technology for treating wastewater.
In 1993 a Constructed Wetland conference was hosted in Midleton, Co. Cork, to address the need for adequate municipal sewage treatment and to explore the opportunities offered by constructed wetland systems. Ten years on and constructed wetland systems are gaining ever more appeal as the technology is becoming more widely accepted and the early systems are demonstrating their effectiveness.
Generally, municipal constructed wetland systems are used after either primary settlement or secondary treatment. For my own municipal scale systems, their use after secondary treatment is the norm, since this lowers the overall land-take and effectively eliminates odour generation provided that the secondary treatment system is functioning effectively. Primary settlement before the wetland is a viable option also, but careful siting is more important and a greater land area is required to achieve the same results.
Constructed wetlands address some of the more challenging aspects of municipal sewage treatment. They are naturally robust systems and have the ability to deal effectively with shock loadings of hydraulic or toxic nature. They can be designed to achieve a consistent, high quality effluent, of greater than 5/5 (BOD/SS) quality where required. Their use following old overloaded municipal systems has been found to be greatly effective, as has their use in polishing the effluent from newly commissioned secondary treatment systems.
The main treatment processes in constructed wetland systems overlap with conventional wastewater treatment processes. Sedimentation, filtration and bacterial activity are the main processes in action. Both aerobic and anaerobic activity occurs, affording different types of microbial treatment. These biological processes, as well as different physical and chemical processes, combine to produce a high quality effluent that can be acceptable for final discharge to watercourses, groundwater or planted percolation areas for evapotranspiration.
Sustainability, the ability to meet the needs of the present without compromising the needs of the future, surely points us in the direction of low energy, low chemical, high quality effluent treatment systems which have the added benefit of providing wetland habitat value where they are used. Constructed wetland systems can help to provide such a sustainable model for sewage treatment in Ireland.
Water and Wetlands on the Farm - published in West Cork Advertiser, 7 May 2004.
Water is something that we are all becoming more conscious of these days. Whether it is water pollution, the challenge of dealing with slurry and farm washings, contamination of our well water or the quality of council mains water, water is in the news and on our minds.
Water doesn’t so much come from our farms as pass through them. Rainwater enters clean and picks up contaminants from the yards, fields and storage tanks. Mains water used for washing carries away the contaminants of the work it has done. As rivers and streams flow through our farms they receive runoff of fertilisers and slurry spread on fields. All of these sources of contamination impact upon the water quality of the receiving environment.
Land-spreading is the standard method of dealing with yard and parlour washings. It can present problems for storage, however, particularly during a wet season. Even small amounts of direct overflow or runoff to streams can cause problem of nutrient enrichment and oxygen depletion. This causes problems for fish and the aquatic insects that they feed on, and over longer periods leads to a general deterioration in water quality and the habitat value of the stream.
Another way to deal with yard and parlour washings is to build a constructed wetland system. This is a fully plastic or clay-lined series of marshes and ponds, planted with the appropriate wetland plants. These filter the water and make it acceptable to discharge into the receiving environment. The slow movement of water in a constructed wetland system allows nutrient-rich sediment to settle out to the base of the system. The plant stems and leaf-litter further slow the water and act as a physical filter for straw, leaves and other debris from the yard. The bacteria living in the wetland feed on the nutrients in the wastewater ensuring that these nutrients are not available for causing enrichment in the receiving environment.
More recently willows are being experimented with, for dealing with yard runoff. The water is channelled through willow-beds, which can be coppiced for fuel. Similar physical, chemical and biological mechanisms work to improve the quality of the water before its final discharge route. The high evapotranspiration rate of willow trees in summer, the release of water through the leaves, transfers much of the water to the air. However winter use is limited due to lack of leaf growth and water uptake.
It may seem ironic that after spending generations trying to drain wetlands, we are now discovering that they have a very useful role to play in the environment. All in all, whether for protecting streams and groundwater from contamination or for improving the quality of water in streams and drains by using in-channel wetlands or even for providing habitat value on the farm, wetlands, new or existing, can be used to great effect.
Buffer Zones for Field Runoff. - published in the West Cork Advertiser, December 2004
We all know of the importance of protecting rivers and streams from yard and parlour washings and slurry from the farm. Yet water from the yards and parlour is not the only source of possible water pollution from farms. Runoff from fields can have an impact upon streams and rivers also.
For ensuring that water running from the fields does not contaminate streams and rivers, it is recommended to have a fenced buffer zone adjacent to drains, streams and other water-courses. The flow of runoff water through the grass verge helps to filter it and allow nutrient absorption. Further improvements can be encouraged by digging a pond in the lowest point between the field and the watercourse. This allows fertilisers and biocides, as well as soil eroded by rainwater, to settle out and fall in concentration before entering the receiving environment. Planting a small wetland area at the inlet and outlet of the pond will further retain nutrients, straw, leaves and other debris.
Even if, by way of appropriate spreading or other filtration measures, you have no negative impact upon streams on your farm, it is a relatively straightforward matter to improve the quality of streams flowing through the farm. Farm drains can be widened slightly and planted as marshes, to filter the water flowing through them. Ponds can be dug intermittently within drains, and even streams, to allow soil to settle and to filter out debris and nutrients within the water.
Keep in mind that it is sometimes necessary to obtain approval from the Fisheries Board before carrying out works within watercourses, so check the legalities before commencement. For ponds over a certain size, planning permission is required. It is also very important not to do more harm than good, so a careful appraisal of the stream and the proposed measures is needed to ensure adequate protection of this sensitive environment.
However, no such paperwork is required to allow a farm drain to fill up naturally with plants or for a wet corner of a field to remain as is. Thick plant growth in open drains and streams is a sure sign that nutrient levels are high enough to need the filtering that the plants offer, so don’t be too hasty in dredging them. Leaving wet corners stay wet and fencing them off from cattle and machinery will provide a natural filter between the field and the stream.
In addition to the benefits to water quality and the obvious advantages of meeting legal obligations of water pollution prevention, there are also considerable wildlife benefits. The aquatic environment of plants, insects, fish and other animals is at its most vibrant and diverse in healthy, clean water. Frogs breed in the still water of ponds, eating pests such as slugs. Birds visit wetland habitats to feed on the dragonflies and other insects that live there, and the more diverse the wetland habitat types, the more diverse the birdlife.
So with buffer zones, wetlands and ponds, you can improve the environmental protection and enhancement for your farm, and create vibrant wildlife habitats in the process.
Household waste: What do we do with it? - published by the West Cork Advertiser 14 January 2005
Bin charges are rising by the year. Existing landfill space is running out, and new sites are being strongly resisted throughout the country. Incineration poses a major health hazard. What do we do with all our rubbish?
If we minimise our waste collectively, we reduce the need for new landfill area and can even eliminate the need for a municipal waste incinerator. On an individual scale it is actually very easy to achieve big reductions.
Separate out all recyclables and take to local bring-sites. Most towns have collection facilities for glass and cans. Some also have collection facilities for plastics and paper (Never burn plastic because the emissions are highly toxic!)
Next, reroute unwanted goods to charity shops instead of the bin. Use reusable containers instead of disposable ones for lunches, freezing etc. Reusable cotton bags have replaced plastic almost overnight since the plastic bag tax was introduced. It is just as easy to apply reuse to other areas of life too.
Composting is another important step. Organic kitchen waste is a big percentage of our weekly waste. Nothing from the garden should be anywhere near a bin, but just in case, remember that garden trimmings and weeds can be readily composted or made into a twig/log pile for hibernating hedgehogs.
Next step, minimise the amount of waste you buy in the form of excess packaging. If you cannot get a pizza without a polystyrene base, a plastic foil wrapper and a glossy cardboard box, why not make your own, or have something else for dinner?
A final step towards reducing your weekly waste (and disposal cost) is to minimise what you buy. Not penury, just a curb on some of the excesses of our throw-away habits.
Sustainable Living, step by step - published by West Cork People 21 October 2005
Sustainability cannot be practised as a tidy, separate “weekly eco-friendly activity”. By its very nature it is an all-encompassing collection of lifestyle habits. From the moment we wake in the morning to the moment we sleep at night, we make choices that impact to a greater or lesser degree on the world around us. Sustainable living is about minimising our impact on the world.
The first easy step is to recycle our clean plastics, glass, cans and paper. Not only does this reduce bin charges, it also helps reduce resource and energy use. We can cut way back on the rubbish we generate by composting degradable kitchen and garden waste. This is very straightforward with a traditional compost heap for garden weedings and trimmings and a rodent-proof worm composting bin for the kitchen waste.
Further reductions can be achieved by shopping carefully, avoiding excessive packaging or purchases that will generate waste when they need disposal. Fireplaces and bonfires of rubbish aren’t an option, being neither legal nor safe. Burning chlorinated plastics produces highly toxic dioxins, one of the main problems for incineration and home burning of rubbish. If you have reduced your weekly waste mountain and want to cut back on costs, why not try to do away with your bin collection completely, and make a 6-monthly trip to the landfill site in Cork instead? That method has served me and my family well for the last five years.
The next step towards sustainable living is energy: what it is used for, where it comes from. Price hikes have started people thinking carefully, and not a moment too soon. Most of our energy in Ireland is derived from fossil fuels – coal, oil and gas. The more electricity we use, the more coal is burned in Moneypoint. The more we drive, the more oil we use. The thinner our home insulation and the hotter the thermostat, the more gas, coal or oil we use for heating. Oil wars have been a feature of the 1990s and 2000s. It is becoming ever clearer that supporting our energy craving is not only completely unsustainable, but is insupportably unethical.
Well, what can we actually do about it? Lots actually. Solar panels can be used to generate hot water. Timber can be burned to heat our homes, and replanted in equal measure. For transport, we can car-pool, bus, cycle or walk, depending on the distance journeyed. The easiest thing to do is to avoid making a car journey for unnecessary things like a pint of milk, but to wait until there are a number of reasons for getting into the car. If electricity prices follow the price of oil we will soon see woolly jumpers, extra blankets, hot-water bottles and a good deal more home insulation being used – and not just by the usual environmentally aware sector of the population.
Water conservation and water pollution is the next obvious area to examine. Every toilet cistern in the Bandon river valley is a spring that ultimately feeds back into the Bandon River. The more clean water we take into our homes and send out dirty, the more polluted our rivers become. We can filter it in treatment units, well installed percolation areas or constructed wetlands, to protect the groundwater which feeds the springs and rivers. But we can also cut down on the volume we use. Low flush toilets or even modern dry-composting toilets, water-saver tap fittings and water efficient washing machines all help. However simple things like fixing leaking taps can make a big difference over a year.
Water falls in plentiful supply on our roofs every month of the year. This can be gathered and used in place of filtered, fluoridated, chlorinated then pumped council mains water (for which we are not even charged!). In its simplest form a water butt under a down-pipe can be used for watering the garden and washing the car and yard. More elaborate systems are available to use rainwater for toilet cisterns, washing machines and with a little more filtration, for drinking, cooking and washing.
If we are what we eat, what in the world are we? The food we eat these days has been grown predominantly with the help of fertilizers and biocides derived from petrochemicals. This is hardly a sustainable practise. Eating organic food means that we can avoid this oil dependence, and support a more sustainable way of agriculture. However, much of the food we buy, organic or not, has travelled a good distance around the globe to reach our shopping basket. If sustainable living is our aim, buying local organic food is a basic necessity. Of course, with all that compost from the kitchen and garden, the best thing is to grow our own. Taking sustainability to its natural conclusion, we need local organic seed: available from Brown Envelope Seeds in Skibbereen!
Finally, take a quick look at our bills? Are they costing the Earth? Switch your electricity to a renewable energy supplier or even check the viability of setting up your own private or group wind-power system. You can even green your phone bill by switching to Call Charity, specifically set up as a fundraiser for charities! When considering savings, investments or pensions, choose an ethical fund. Anything else is hardly a sustainable approach to retirement. For maximum sustainability all round, live simply!
Saving the Seeds of the Future - published in The Irish Examiner's Farming Section, 8 February 2001.
Overlooking Sliabh Bearnach in East Clare, a nine acre site is tucked quietly into the roadside in Capparoe. Like many other small farms in the country, its present use is to grow fruit and vegetables. Despite its scenic surroundings and inconspicuous appearance, this site is home to probably one of the most important collections of food seeds and plants in the country. It is the site of the Irish Seed Savers Association.
When the large seed companies of the EU and the USA have selected a handful of profitable species for mass production, the thousands of less profitable varieties fall inevitably by the wayside. While we gain uniformity, shelf-life and glossiness we loose the diversity, the pest and disease resistance, the flavour and variety of flavours, the nutrient content; in fact, nearly all of the traits we used to look for in an apple or a spud or any other fruit or vegetable.
What the Irish Seed Savers Association is doing is collecting old and rare varieties of all manner of fruit and vegetable seed. Members grow the produce in their own gardens and save the seed for the following year and more. In this way, they have literally resurrected rare varieties and even a few that were thought to have been extinct.
When I visited the ISSA recently, Anita Hayes, its founder, proudly showed off a huge cauliflower plant, which had been extinct but for a handful of seed in a seed-bank. A row of them was being carefully grown on in a polytunnel to gather more seed, safe from cross pollination from other brassicas (the cabbage family). They will then be sent out around the country to members for further seed saving and mealtime savouring. Resurrected as surely as Jesus raised Lazarus from the dead – a miracle indeed in the face of the global drive towards bigger, better, blander by multinational corporations.
“The Irish Seed Savers Association is a voluntary organisation dedicated to the location and preservation of traditional varieties of fruit and vegetables”, says their Spring 2001 newsletter. Its the first high-profile project was to compile a list and collection of old Irish apple trees. With Dr. Keith Lamb, whose PhD. on Irish apples supplied an indispensable foundation upon which to start, the ISSA now provides its members with a selection of apple trees many times broader than the short list of varieties actually legally traded in within the EU. Such corporate driven legislation is not only the cause of much ridicule of Brussels policy makers, it also causes considerable damage to genetic bio-diversity and long-term food security – be it from pests, diseases or the limitations of privatisation.
Quietly in defiance, a new collection of apple tree slips is sitting in neat rows behind the office/storage rooms. Anita tells me that they are grown from cuttings, without the laborious need for grafting onto hardy rootstock. They all come from rare trees of a single owner after whom they are all named for the moment. When they reach fruiting age they may be given names of their own, but until then they hold the mystique of exotic unknown fruit. What is known is that they grow well from cuttings, are hardy in the Irish climate and thrive in thin or damp soil. All important traits for Irish conditions. Surely not the traits selected for in your standard supermarket green or spongy red. They are also good tasty cookers, I am told.
As we wandered around the site we passed the newly planted grove of native deciduous trees, the growing collection of rare Irish apple trees, the polytnnels and raised beds for seed propagation and seed drying and storage facilities. Pumpkin seeds were drying on shelves, onions were hanging up, being trialled for ease of saving through the winter and the apple tree cuttings rooting busily for the Spring.
As I was leaving, Anita pointed to a notice board of projects elsewhere in the world. While everybody involved in a particular environmental area is focussed on their own project, she said, it is important to remember other parts of the world where such action was sometimes treated with imprisonment, harassment or death. The ISSA are giving 1% of their income this year to an apple tree project in Tibet, to replace the mountain tree-cutting by the Chinese. In her words "Tibet is the home of the apple originally – surely then we owe them our support."
If you have an old apple tree in your garden and you think it may be a rarity, why not contact the ISSA at Capparoe, Scariff, Co. Clare, 061 921866 or email@example.com Who knows, maybe you have the last of a particular type of apple. Indeed any fruit or vegetable which may be a rarity would be worth spreading around and saving for the future.
Bóthar and Irish Agriculture - published in The Irish Examiner's Farming Section 19 April 2001
Irish agriculture is in something of a state of turmoil at present. The BSE crisis, whatever its cause may be, is highlighting something very rotten in the state of farming, as Shakespeare may have said for Hamlet under different circumstances. Other problems are present also. The family farm is becoming a thing of the past. There are fewer, larger farms in the country, and larger, heavier machinery which compacts the soil. There is an ever declining trust for the food we see in supermarkets, such is the rise in food allergies, the awareness of chemical residues and the unknowns of genetic engineering. Within Europe, we are producing too much food, and yet the quality is declining. What has gone wrong with the agricultural policies and practises as they now exist?
Overproduction of food seems to be a very Western habit. The rich nations of the Northern Hemisphere produce too much food, while the poorer nations of the Southern Hemisphere go hungry. Foreign aid does not always get to the people who are in need of it. In fact, one definition of foreign aid is; ‘poor people in a rich country giving money to rich people in a poor country’. While this is not always the case, it is not uncommon for European aid policies to ultimately work for the benefit of the European economy, rather than the well-being of the receiving nation.
On food and farming, a charity that seems to have evaded this danger of inappropriate distribution of funding is Bothar. Bothar is the charity that sends cows and goats to African families. Bothar aims to help such families to help themselves by enabling them to increase their supply of food, as milk and meat. Try as I might, I cannot picture the elite in these nations procuring a goat as easily as they procure cash.
Jeremy Meehan, a teacher at Cobh, Co. Cork, has been involved with Boher for several years. He explained some of the finer details to me. When a goat is received, the first female kid born is given to another family in the community, so that a potentially endless cycle of self-reliance is born. To protect the local environment, the participating families operate what is called a ‘zero grazing zone’. Within these areas, elephant grass is cut by hand and fed to the goats in their own enclosure. In this way, the impact on the delicate ecosystem of the area is not only protected from the new goats, but from other grazing pressure also. Thus the soil erosion which can follow overgrazing is stopped and the soil can build up instead of being washed away.
Bothar has a new video which is to be launched in the near future. In it, Mr. Meehan and his students explain their fund raising involvement and why they participate. Part of the video shows an interview with an eight year old boy in Africa and his first-hand experience with Bothar’s work. The goat that his family received provides enough milk for their own use and some surplus which, he says, enables his mother to buy clothes and to pay for his education. The goat is portrayed by the child as something of a celebrity, such are the benefits that she has brought to his family. The care and attention shown the goat seems to be in stark contrast to the pressures that modern Irish agriculture puts on both the farm animals and on farmers themselves.
Neither the poverty of the African situation, which Bothar seeks to heal, nor the headlong tumble into global agribusiness as it is being practised in Ireland, seem ideal. So, where is the bridge between these two extremes of farming? Here in Ireland, as in other Western nations, we have concentrated on producing food in bulk for export. We have bought into the consumer society, whether we intended to or not. Indeed, many people appear quite happy here for the moment. We work for our money and expect it to buy us happiness and security, which it never seems to do. By contrast, the families that receive a goat from Bothar are so far on the other end of the economic spectrum that one such animal will dramatically improve their self reliance, their ability to produce their own food and a small source of income for clothes and education.
In Ireland, small scale family farming has provided food for people for the last five thousand years, with the occasional notable blip, it must be said. Now, in the age of global markets and factory farms, this mainstay of our rural economy is becoming eroded. If we loose the wherewithal to produce our own food, we become as vulnerable as ever we were in the past.
Is there anything to learn from the self reliance of the Bothar activities? Would we be better to grow good food for our own families and communities, rather than buying from the cheapest producer on the global market and selling to an unreliable anonymous global consumer? Would we be better to take the production of food back out of the hands of large scale agribusiness and hand it back to the small producers of the country?
The difference between the past and the present is that now we have much more control over our circumstances. In some senses we are taking that control already. People increasingly want to buy food grown without chemicals and food they can trust. At the same time, country markets throughout the country are returning steadily. These provide an opportunity for people to meet those who grow their food. In an age of anonymity and the emergence of almost paranoid ‘accountability’, what better way can there be of tracing our food to its source? By selling directly from producer to consumer, we are building up again the solid base of agriculture in Ireland. If the sands of the global economy shift too much to build reliable foundations, maybe the small scale approach of Bothar and our own country market networks can build a secure food base throughout the world.
© FH Wetland Systems, 2012