The chalk streams and most people who live in the Colne catchment rely on groundwater for their water supply. As the catchment’s population increases so does the demand for water, placing immense pressure on the groundwater resource, and causing the Colne’s headwaters to suffer  increasingly from low flows or dry up altogether. If our streams and rivers are to continue to survive, something must be done to tackle this issue.

There are a variety of industries located within the Colne catchment, many of which are water dependent, requiring a reliable source of water. Notably, households use 96% of the water in the catchment with the remainder being used by activities such as agriculture, horticulture and quarrying. The average daily water use in households in the Colne catchment is a massive 182 litres per person per day in properties without a water meter, the highest in Europe. This amount is some 32 litres above the national average and 42 litres above the UK Government’s target for water use   Reducing per capita demand will be key to improving flows in the catchment’s chalk streams to ensure their survival for future generations.

Although lack of water is a key issue affecting many of the catchment’s rivers, flooding can also be a problem particularly in the lower Colne.   The Colne catchment has experienced a great deal of development, with many parts of the catchment now densely populated. Periods of heavy rain such as those experienced in 2007, 2012, 2014 and 2024 add to the risk of flooding but this can be better managed by slowing down the speed at which rain run-off enters the river, using sustainable urban drainage and by increasing connectivity with the floodplain.

Design by LTD Design Consultants and build by Garganey Consulting. From an original concept by the Herts and Middlesex Wildlife Trust.