While Stroud, Key Intelligence’s home town, prides itself on being ‘at the heart of the Five Valleys’, surrounded by rolling Cotswold hills, babbling brooks and ‘Cider with Rosie’ countryside, there is a more sinister side to having five water-courses, and all the lesser streams that feed them, converging on the town. Stroud has been designated by the Environment Agency as at risk of destructive flash-flooding, of the kind that famously washed much of Boscastle into the sea in 2004.
While not as severe as that designation would suggest, the floods of 2007 caused extensive damage across the Stroud district, and I remember vividly trying to get home on the evening the water peak struck and the mounting desperation of finding every road blocked by flood-water. And there has been some degree of flooding in Stroud in every year since.
For a number of reasons, including the vast extent of the water catchment area, the distribution of the ‘at risk’ communities, and their own natural beauty, the Stroud Valleys do not lend themselves to hard-engineered flood protection. Instead, the District and County Councils, the Environment Agency, the Regional Flood and Coastal Committee, local landowners, and a host of volunteers, amongst whose number I count myself, have come together to implement Natural Flood Management (NFM).
NFM aims, by natural means, both to reduce the downstream maximum water height of a flood and to delay its arrival, increasing the time available to prepare for flooding. Those aims are being achieved simply by restricting the progress of water through the catchment area of the valleys.
Over the past 12 months, we have undertaken a structured programme of diverting and partially-blocking streams, to slow the flow and push excess water into preferred channels, ponds and ditches, out across areas of land where it can soak or evaporate away more safely and into newly-created storage areas.
My own involvement has been in helping to create various woody debris obstacles in a Gloucestershire Wildlife Trust reserve spanning the Dillay Brook, one of several streams that feed into the Slad, which is the watercourse deemed most likely to create a destructive flash-flood in Stroud.
These obstacles are leaky enough to allow the water in the brook to flow freely under normal circumstances, but prevent surges following heavy rainfall. In a downpour, their positive effect is evident, with muddy pools quickly forming behind them while the brook flows almost normally, tamely and calmly, downstream, towards Stroud.
We sourced the large woody debris from the stream-side woodland, from a great deal of coppicing, and by felling unwanted trees. This woodland management activity, in reducing the tree canopy, has allowed more light onto the stream bank, encouraging new plants to grow and starting the chain of attracting new wildlife. Elsewhere, new trees and reeds have been deliberately planted to slow down the water and they too have had beneficial effects on the natural environment.
It is pleasing to know that, while some other flood-affected communities are throwing concrete, machinery and vast amounts of money at their flooding problem, Stroud, with a little bit of effort from cold- and mud-tolerant people, is quietly reducing its risk in a creative and positive way.
-Adrian Bishop
