Locals to help solve BASSENTHWAITE LAKE’S nutrient problems

Date: Saturday 8th March 2003

STAFF from the Environment Agency will be out and about around Bassenthwaite Lake in the coming weeks to try and find out the source of nutrients which are causing problems in the lake.

STAFF from the Environment Agency will be out and about around Bassenthwaite Lake in the coming weeks to try and find out the source of nutrients which are causing problems in the lake.

They will be visiting hoteliers, farmers and tourist site operators in a bid to improve the quality of water in one of Cumbria’s best-known lakes which is home to the vendace, a rare Ice Age species of fish which is found only in two locations in Britain.

The vendace likes clear, cool lakes deep enough to protect against heat stress and oxygen shortages in summer. Estimates of the population in the lake, made using echo sounders, range from 80,000 to 172,000.

Between now and the end of April, agency staff will be visiting more than 50 premises alongside Bassenthwaite Lake in a project to identify possible factors affecting water quality. The agency is keen to discover sources of nutrients and sediment which enrich the lake and cause blooms of potentially harmful algae.

Domestic sewage, farm waste and fertiliser run-off can increase nutrient levels in Bassenthwaite Lake. Sediment can be released by erosion of river banks, poor drainage and damage caused by farm animals. In addition, some forestry practices can contribute to both problems.


Now the agency wants to find out where the nutrients and sediment are coming from and what levels are getting into the lake and is asking owners of farms and businesses to help.

Advice and information on practices that will help protect the lake, such as sewage treatment and disposal and land management, will be offered.

Environment officer Ian Law insists the agency is not looking to prosecute people and that co-operation is the key to this campaign.

He said: “We will be saying to people, this is your lake and your environment, help to take care of it.”

Bassenthwaite suffered a major outbreak of the toxic blue green algae last September and questions were subsequently tabled in the House of Commons by local MP Tony Cunningham.

Further problems arise when the algae is washed out of the lake down the River Derwent. Anglers had threatened court action over the outbreak which was put on hold only when the Environment Agency agreed to set up a working party to plan the treatment of the lake with barley straw.

Stan Payne, chairman of the Derwent Owners’ Association, said a decision on legal action would be considered at the end of May and warned that a long hot spell with little wind could lead to the death of every fish in Bassenthwaite Lake, leaving the famous ospreys, which have nested nearby, without food.

Anne Jackson, the Environment Agency’s environment officer for the area, said: “Bassenthwaite Lake is an important asset and popular with local people and visitors but high nutrient levels are having an adverse effect on water quality.

“These visits will help us address part of the problem. We’re not looking for illegal discharges or to prosecute offenders, but in some cases we might be able to give advice so people can prevent these problems occurring.”

One of the problems on Bassenthwaite is the shallowness of the lake which leads to a build up of sediment.


Blue green algae are natural inhabitants of many inland waters. When not in excess, they make a contribution to the aquatic biology of natural waters, but the algal scum can poison animals and harm humans.

The worst times are May and September when the algae can last for days or weeks. Mr. Law said the agency was looking at all options, including the straw bales, to minimise problems in the lake.

“Initially we are investigating the east side of the lake and going to all the premises there. We are trying to quantify the amount of nutrients being released, for instance from fertilisers spread by farmers and hotel sewage systems, and we rely on the co-operation of locals.

“If we manage to identify problems we will extend the survey round the whole of the Bassenthwaite catchment, which is a huge area, and try to promote good practice,” he said.

With 14 rivers and streams feeding into it, Bassenthwaite drains the largest area of any Lake District lake. Some years ago a phosphate removal system was installed at Keswick sewage works, a plant which serves a population of more than 10,000 and discharges treated effluent into the River Derwent before it enters the lake.

Mr. Law said the next step would be to build a working partnership with people to protect the lake.

“We are not in the business of blaming anybody and in doing this review we will avoid adding to the red tape which people already face in everyday life,” he added.

Water quality problems in Bassenthwaite Lake are being tackled by a sub-group of the Lake District Still Waters Partnership, formed last year by the Environment Agency, Lake District National Park Authority, English Nature, National Trust, United Utilities, the Centre for Ecology and Hydrology and the Freshwater Biological Association. The Partnership has been set up to co-ordinate work to protect lakes and tarns throughout the Lake District