Using Permaculture Design to Prepare for Floods
Permaculture design helps us to look at the landscape with greater understanding and enables us to design more resilient gardens, homes and settlements. Kate Fox describes how a flood forced her to re-evaluate her garden design and ultimately her life.
Nowadays extreme weather is becoming more and more common and it seems that 'freak events' are becoming normal; in fact there was extreme storm after extreme storm all winter affecting a lot of the UK with flooding, tidal surges, power cuts, fallen trees and damage from high winds. Any of us can be affected by extreme weather at any time of the year, as I know after experiencing localised flooding in June 2012 where only 10 properties were affected which are nowhere near a river, flood plain or the sea and don't appear on the Environment Agency's flood risk map.
Climate change, extreme weather, storms and flooding around the world seem to be rarely out of the headlines. June 2012 was reported as the UK's wettest June on record. Some areas received a month's worth of rain in 24 hours on top of generally higher than average rainfall. This caused widespread flooding in places including Carlisle and Aberystwyth and localised flooding elsewhere including where we lived in West Sussex.
Ironically just a few weeks before our flood I had been asked to write a short article about how the drought was affecting our area (south east England) after having the driest two year period since records began. We had been entering a water crisis: the groundwater was at a worryingly all time low level and we had a regional water shortage. All that had changed by the time June arrived!
Why we flooded
At the end of the terrace of ten cottages where we lived there is a small stream (no more than a trickle normally). It winds its way through a woodland before entering a concrete culvert which takes it under the main road and away eventually to the river. What we discovered is that in extreme rain events the culvert simply cannot cope with the quantity of water so it backs up, flooding the area where we lived which was a relatively low point in the wider landscape. We moved out of the house a year ago but I have heard that there was another flood in this year of the same scale as the one we experienced.
How we managed the situation at the time
The rate that the water rose was scary. We were alerted by neighbours early in the morning and found our van already up to its sills in floodwater on the drive. By the time we had moved it to higher ground the water was about 50cm deep and within about another half an hour it was up to over a metre. We had to prioritise what to try to save as we couldn't possibly move everything and we had already lost hope of saving the power tools that were submerged in the workshop.
After our van we moved the very worried chickens out of their run into a shed at the top of the garden. When we designed the chicken run in 2008, we did not have flooding in mind as it hadn't happened in the year that we observed our plot. However we did build a hen house on legs, so even if we'd not been there the chickens could have got themselves somewhere safe (if they had the brains to do so!).
Next we took all our home grown pork out of the freezer that was already half full of water - we couldn't bear to lose that after all the effort that went into producing such high quality meat from our 'permaculture pigs'! After that we decided to just help other people in the terrace try to save any valuable possessions, especially the elderly lady in her 90s a few doors down who had a car, mobility scooter, power tools and a freezer full of food in her garage.
We were lucky that only our garden flooded and not our house - to have a house flood must be devastating. The contents of our woodworking workshop and store (for wood and home grown produce) suffered quite a lot of damage meaning that we had to make an insurance claim mainly for tools and carpentry timber; as luck would have it we had reinsured our home and contents only two days before the flood! But the worst thing was the clean up. The entire contents of our workshop including hundreds of carefully sorted pieces of wood (mostly reclaimed), some eco building materials such as lime plaster and solar panels and all sorts of other things all rose up with the water, floated about a bit and then got dumped in a huge higgledy piggledy heap meaning that we couldn't actually open the door to get in once the water had gone. It took a few weeks to sort everything out, stack the wood up to dry and clean up all the debris and silt that the flood had brought.
What we learnt on reflection
The main thing that became apparent was the mistakes we had made when designing our 'microholding'. When looking at our boundaries we had not properly taken into account what was beyond the physical boundary of our property. Therefore we had overlooked the stream 100m away and the possible effect it could have on our land. We had also failed to notice that our property lay at one of the lowest points in the wider landscape. When speaking to the neighbours after the flood we discovered that the area had flooded twice before in the past 15 years. If we had spoken to them during our observation period we would have been able to design in some more resilience to this kind of event.
Design for extreme weather events
When designing a garden, microholding, smallholding or other kind of plot in the future I will always bear in mind extreme weather events including wind, rain, snow and ice. It is probably a good idea to look up weather records if possible, to look for any patterns and any potential threats, and definitely speak to local people.
Harvest fertility in flood water in raised beds
But flooding is not all negative, it can also have its benefits. As mentioned above, our flood came after a prolonged dry period and being on extremely sandy soil everything had been struggling for moisture even though the vegetable beds were heavily mulched. The main consequence of the flood on our growing area and crops was that they had a jolly good watering without us having to do anything! This is pretty much how crops are watered in arid regions such as southern Spain where each holding gets 'flood irrigation' on a rota system. If flooding or water-logging is a potential problem on a plot then this is a good reason to consider raised beds - our beds were raised (only about 15-30cm high) and this definitely helped with drainage when the floodwater receded but the ground was still saturated.
The only lasting effect on our produce was that we were careful to wash it properly just in case of anything nasty in the floodwater.
Surprisingly our pond did not suffer negatively - I was really concerned when I saw our six resident pond skaters scattered about on top of the floodwater near the workshop, in the greenhouse and even in the street but when the water receded they were all back on top of the little pond. They had probably been having a great time with all that water to stretch their legs on!
Work with nature - create water meadows
Over the last year the orchard where we keep our geese on a friend's smallholding floods quite often but the geese love swimming and washing their heads in the large pond that appears. Without the geese in that area the temporary body of water would probably be seen as a nuisance or an eyesore but once our friends realised that water naturally wants to collect in that spot they started talking about lining the area with clay so that the pond can be permanent, therefore not only benefitting the geese but also enhancing general biodiversity. Only one apple tree has died due to waterlogging so the benefits to the geese and wider ecosystem can be seen to outweigh that loss.
Considerations for re-designing
After experiencing the flood we thought about what we could do to tweak our design that would build in resilience to further occurrences. Our workshop and store were block-built and could not be moved elsewhere on site but they were in need of a new roof so we considered extending the buildings upwards and either having a suspended floor or two storeys (the next door neighbour already had planning permission to build a two storey garage/store). We had also talked a few times about boarding out the roof space of our oak framed loggia (which was next to the workshop) for storing woodworking timber rather than storing it at ground level and this could easily be done with some of the timber we already had.
However, building work had cost implications and as we would have done the work ourselves, the time we had available also had to be considered. This led us to think more about our longer term plans and question how long we wanted to stay at this property and how much we wanted to invest in it. With my partner's work being sustainable building and woodworking/carpentry we had always thought that one day we would like to design and build our own house.
In the end it turned out that the flooding was a catalyst for us re-designing our whole lives! We looked at what we had and what we needed and wanted (not just possessions), analysed our skills, resources, limitations, opportunities and concerns and came up with a design that meant we sold our house to move on to pastures new and the next step in our journey!
Environment Agency Flood Risk Map: www.environment-agency.gov.uk/homeandleisure/37837.aspx
Editor, Maddy Harland, writes:
Permaculture design looks at whole landscapes and bioregions. Flood defence should not be localised strategies. We need to look at whole ecosystems. Denuded hillsides over-grazed with animals with compacted soils will send rainwater down towards the valleys on to the floodplain (where we foolishly tend to build our settlements). Add to this the removal of hedgrerows (good barriers to slow down water and harvest any debris washed down the slope) and the habit of ploughing slopes vertically rather than on the contour for grain crops, and we are creating a rapid runoff of excess rainwater and top soil.
Permaculture design advocates reforesting the ridges and high ground, contour and keyline ploughing, developing swales planted with treecrops on the contours to both harvest rain in excessively dry periods to irrigate the crops, and to create a physical barrier or soil bund to slow down runoff in times of flood. The land is a sponge if we allow it to be by adding these features rather than working against natural forces. We need to re-establish old practices such as using flood in water meadows to create fertility and to stop building culverts to redirect rivers. We also need to retrofit our old drainage systems and look at flood resilient architecture pioneered by the Dutch.
For more insights into permaculture design for farms, woodland and the wider landscape as well as gardens and settlements see: