This is the final stage in a wider project which has seen successful repairs to both the Vanburgh Bridge and the Cascades. Due to the successful work on the Cascades, we can now undertake a wet dredge, which is far less disruptive. This is the final stage in a wider project which has seen successful repairs to both the Vanburgh Bridge and the Cascades.
Due to the successful work on the Cascades, we can now undertake a wet dredge, which is far less disruptive. Originally, we had planned to conduct a dry dredge, which was set to begin in March 2020. However due to the global COVID-19 pandemic and restrictions, the project had to be delayed. This delay allowed us to carry out crucial repairs to the cascade and allowed us to look for further opportunities in funding streams and delivery. We are now incredibly happy to say the project is back on track with initial preparation works being carried out in January 2022.
An important part of the Blenheim World Heritage Site, Queen Pool has become heavily silted which puts its well-developed ecosystem at risk. The biggest threat comes from the lake’s significant build-up of silt: 70% of the water is less than 30cm deep when it should be around two metres to support the existent ecosystem and the creatures who depend on it. If we don’t dredge the lake, we are at risk of it drying up completely.
The lake’s ecosystem is high in nitrogen and phosphates creating the perfect environment for algae, an important food source for the lake’s many fish, amphibians, and insects. The area is a designated Site of Significant Scientific Importance (SSSI) and attracts many overwintering wading birds which rely on the lake for food.
Wildlife surveys carried out by BSG Ecology ahead of the dredging has revealed the estate is home to a huge variety of wildlife including more than 50% of the UK’s different bat species, 36 types of wildfowl, water voles, badgers, otters, reptiles and a number of rare insect species.
The water vole lives along rivers, streams and ditches and around ponds and lakes, which makes our Queen Pool the perfect habitat for them. Due to the dredge activity taking place where the water voles reside, they are moving to a safe place for the duration of the work, allowing them to continue to live happily in the local area. We are working with Ecologists to make sure that the moving of the voles follows the good practice set out in the water vole Conservation Handbook, and fully licensed by Natural England.
When the Queen Pool water level was lowered in October 2018, all the fish were moved to the Great Lake and a net separates the two water habitats.