After the completion of the project with CEH and Lancaster University in 2010, an ad hoc committee of local people (the Loweswater Care Partnership) maintained the momentum of interest and work on the lake through continued regular meetings and lake monitoring via samples collected by the EA. In early 2012, Defra announced funding for a new programme of work to tackle diffuse pollution from rural and urban land use – the Catchment Restoration Fund (CRF). Grants totalling £24.5M were distributed to support 42 projects running over 2012-2015. Our project ”Improving water quality in Loweswater” received £327k and was completed in September 2015.
Preliminary surveys of the land and farming infrastructure by independent consultants showed that there were many measures that could be implemented within the available budget to reduce phosphorus loadings to the lake and its catchment. About half of the total budget was spent making improvements at five farms in the lake catchment – this included construction of new fencing along becks to prevent stock access, land drainage channels to facilitate run-off, new cattle and sheep sheds, new roofing over yards and an expanded slurry tank as well as the acquisition of a sward slitter and lifter for the benefit of all the farms in the catchment.
New Fencing along lake shore
We also undertook two further studies to fill in gaps in our knowledge of two key lake characteristics. Firstly, we were able to show that, compared to other known sources, deposits from waterfowl visiting the lake were likely to be insignificant sources of phosphorus nutrients. Secondly, the detailed sampling of lake deposits and water allowed us to calculate that the annual recycling of phosphorus from lake sediments during the summer period of stratification was equivalent to only about 8% of the total input load in 2013. From a mass balance around the lake, about 60% of the incoming total fresh phosphorus, which comes mainly from feeder streams, was permanently buried in lake sediments in 2013, with the remainder discharged in the Dub Beck outflow.
One of the more innovative interventions looked at in the project was the use of ultrasound to destroy algae, particularly the blue-greens. The ultrasound system used was beset with a number of problems over the 1½ year operational period - notwithstanding the resultant uncertainties in the levels of ultrasound exposure for significant periods of time, this treatment had no discernible effect at any time in terms of the numbers of algal species or the length of algal filaments.
Overall, the results of the project’s water quality monitoring programme indicated that the lake shows signs of improvement in its chemical status, but still classifies as mesotrophic and, that under the Water Framework Directive, the lake is still classified as of moderate ecological status.It is anticipated that any impact on the lake’s water quality following this programme of work, particularly improvements in farm infrastructures and practices, may take many years to be realised.
Looking outside its technical achievements, the project has demonstrated the continued interest and support of the local community in attending local meetings over the project’s course and the value of the ongoing partnership formed during previous Loweswater projects between key stakeholders – the National Trust, the Environment Agency, Natural England, local farmers/residents and West Cumbria Rivers Trust.