Sustainability and the natural environment are top of our agenda at Denmark Farm. So having systems in place that save water and treat waste water using natural processes is very important. We aim to be a site which inspires all our visitors to consider their own water sustainability.
It is not just us who think this work is important. We have recently been awarded first runner up in Green Key’s International Best Practise Competition with a Water Sustainability Theme.
Our Water Management Systems include:
- WET (Wetland Ecosystem Treatment) System for treating waste water using natural processes. The first of its kind in Ceredigion.
- Solar water heating system is also in place on the roof of our offices, providing hot water for our visitor centre when the sun shines.
- Rainwater flushing toilets in our visitor centre and accommodation.
- Biomass boilers in the basement of our Eco Lodge provide hot water and heating to accommodation guests and farmhouse tenants.
- Rainwater butts which collect roof water for watering plants in our kitchen garden and courtyard area.
- Our 30 year conservation management plan has seen significant actions undertaken to re-wet grasslands and hold water on site rather than encourage drainage. Actions include: pond creation, lake creations, blocking up drains, creating shallow scrapes. Huge benefits for biodiversity.
These systems can serve 6 part time staff, 2 permanent farmhouse tenants, up to 12 guests in our Eco Lodge, 10 guests in our dormitories, plus campers and course participants.
Our WET System
The capacity of natural processes to renew and clean water is amazing. Soil filters water on its way to wells and springs. Plants and microorganisms act as a biological purifier. At Denmark Farm Conservation Centre, we are harnessing these natural attributes with a Wetland Ecosystem Treatment (WET) System, in anticipation of increased sewerage loads.
The WET system was designed and built by Biologic Design in 2011. It is 60m x 40m in size and was located in line with the existing soakaway just below the old settlement tank. It comprises an inlet pool and 4 swales as a total absorption system with no pipe outfall and has capacity to serve full-time population of 25-30 capacity. To prevent the possibility of septic waste water entering the groundwater or nearby watercourse we allowed for the inlet pool and top two swales to be lined with a self-sealing geo-synthetic clay liner. This was agreed with the Environment Agency as good mitigation against the possibility of a wastewater causing a pollution accident. So, the system is well contained and 5 years in there have been no issues. The whole system cost approx. £16,000.00 (ex VAT).
The pool and swales have been planted up with native, marginal species (already present in Ceredigion) of wetland wildflowers and, significantly, 3,000 osier willow which will play a crucial role in taking up nutrients from waste water and converting it into biomass.
A WET System has specially designed and constructed ponds and earth banks, densely planted with wetland trees and marginal plants. As wastewater flows through, it is both purified by microbiological action and transpired by growing plants. In the process, a beautiful, species-rich wildlife habitat is created, including a willow resource that can be used for basketry, hurdles, garden features or fuel, depending on the coppice cycle.
Additionally, a WET System requires minimal imports of resources – the site’s soil (rather than quarried gravel) filters the wastewater, fossil fuels are only consumed during construction and there is no ongoing electricity use. In fact, the whole process increases in efficiency over time, as new soil builds up and root systems extend – both of which also increase carbon dioxide storage as biomass, whereas conventional treatment systems need regular maintenance and energy inputs.
The only maintenance that the WET System has required in its first 5 years is some weeding of encroaching bramble and the annual willow coppicing day. This work is undertaken by volunteers and participants attending our willow basketry course.
The WET System provides a small income as a by-product as the willow stools produce many roads for use in basket-making and other willow crafts. We run courses annually on site in such traditional crafts. This gives us a renewable supply of craft material. Any unused willow roads are bundled and dried to be kindling for our Eco Lodge wood burning stoves or faggots for starting our community clay coven. So nothing goes to waste.
The WET System is designed for a capacity of 25-30 people, so it is future proofed for times ahead when all accommodation, farmhouse and offices are full to capacity. The willow coppice will become more productive with time, producing greater amounts of biomass than it does currently. As the pools in the system age, new wildlife will colonise, increasing biodiversity.
Rainwater Flushing Toilets
Two IBC units are situated behind the visitor centre. Created in 2008, this was a DIY project completed with a budget of just a few hundred pounds. The system might be simple, but it’s effective. The tanks supply all the water we need to flush the 5 toilets in the training centre and office. These are used by staff, course participants, volunteers and overnight guests in our dormitories and campsite. Since the system was installed we have only once needed to switch to mains water to flush the toilets.
The rainwater flushing toilets and rainwater butts save us the water rates that otherwise we would incur.
Water and Our Conservation Management Plan
Denmark Farm takes a holistic approach to water management as a key element of natural habitats. We understand that everything is connected (our motto) and plenty of steps have been taken to manage water for the long term sustainability of the site.
How we have managed water across our 40 acres of land is a key aspect of our conservation management plan. Surrounding landowners have significantly drained land for improved grazing and filled in ponds which not only encourages an environment of monoculture grassland but also contributes significantly to flooding as lowlands have to take on the additional run off which otherwise would be absorbed by traditional meadows and wetlands. In contrast, over the past 30 years Denmark Farm have blocked up drains, encouraged wet meadows, created new shallow scrapes, dug new ponds and created a lake complete with an artificial otter holt. Over 10 acres of new mixed broadleaf woodland has been planted. Where previously groundwater passed through heavily grazed grassland, the new trees now take up water through their roots and transpire it through their leaves.
The result, in terms of water management, means a landscape that holds more water, which is better for lowlands and results in a much richer biodiversity with animals such as otter and snipe seen in recent years. Denmark Farm is a mosaic of habitats and the wet meadows, marshes and open water which both wildlife and visitors can appreciate.
This ecosystem approach fits our philosophy of working with, rather than against nature. And the beauty of it is that we have fewer costs and many benefits. So why aren’t these systems more common? One hurdle may be lack of familiarity, which is where we come in. Our WET System is the first in Ceredigion and one of only a few in Wales – so far! As a demonstration site, we can show statutory bodies, trainees and visitors the potential for farms and other industries that have liquid organic waste. With biodiversity benefiting too, the future looks bright for wetland wildlife.
There are huge non-financial benefits to our WET System and approach to managing wetlands across the site in terms of added biodiversity and creation of micro-habitats. This in turn makes our site a haven for wildlife which attracts visitors who bring an income form the courses they attend (including studying, drawing and photographing wildlife) to the accommodation guests who want to take a break in a nature reserve where they can enjoy thriving ecosystems.
We are currently reviewing our conservation management plan for the whole site. This will be a 20 year plan including management of wetlands, woodlands and interpretation for visitors.
We hope that in terms of benefits to others, that our visitors are inspired to look further into these practises and how they could be applied to their own land or projects.