What are the possible solutions to the Verulamium Lake crisis?
PUBLISHED: 12:19 11 September 2015 | UPDATED: 13:41 11 September 2015
Following a passionate community response to the poor state of Verulamium lake, St Albans district council (SADC) has been looking into various solutions that offer an alternative to draining or dredging it.
Many residents have suggested this was the only option to prevent further diseases developing in the water, but others have come forward with their own solutions.
The Herts Advertiser took a stroll around the lake with Cllr Daniel Chichester-Miles, portfolio holder for environment, Richard Shwe, head of community services, Verulam ward Cllr Jessica Chivers, and Dan Flitton, a green spaces officer from the district council, to discuss their plans.
There is an excess of litter in and around the lake, with much of it caught in the reeds, which adds to the water pollution.
District council solution: The installation of signs around the lake, designed with the help of school children, to discourage littering.
Low oxygen levels in the water
A lack of vegetation, slow water flow, and build up of silt has led to poorly oxygenated water, provides a breeding ground for diseases like avian botulism.
District council solution: Artificial reed beds installed within the next 12 months with added vegetation to help oxygenate the water.
A poor water flow from the River Ver through the sluice gate has meant the water in the lake remains stagnant and unable to flush out pollution.
District council solution: SADC is entitled to extract 20 cubic metres of water per day from aquifers (underground layers of water) around the district. A possible option is to use an aquifer just north of the lake to help pump fresh water into the lake. This comes with its own risks as the aquifers feed into springs that feed into the river Ver.
Cllr Chichester-Miles said: “As a chalk stream river it is a rare habitat of which Hertfordshire has a significant proportion of the world’s stock. As such we would need to consult with engineers and importantly the wider community. If viable this would have the advantage of allowing us to close the sluice gates and provide a sustainable solution to a problem which has plagued the lake for the last 50 years.”
There is a thick layer of silt at the bottom of the lake mainly made up of decades of accumulated duck faeces and dirt, providing a breeding ground for diseases and causing the lake to floodafter heavy rainfall.
District council solution: The council has refused to dig out or dredge the lake, but is in talks with a local engineer who specialises in a very small floating digger, Truxor. This machine is a less intrusive digger that gradually removes the silt, and currently costings and the extent of silt removal are being examined.
Cllr Chichester-Miles said: “If coupled with a permanent ‘cure’ to the lake silting up then this would be a finite process rather than a continuous effort.”
The district council will update the Herts Advertiser about whether they choose this solution after a meeting with the engineer at the end of the month.
Poor diet of ducks
A diet of low-nutrient bread has resulting in St Albans’ duck population becoming unwell and dependent on humans for their food. Their faeces also contains chemicals from the bread they can’t digest, and this, in turn, pollutes the water further.
District council solution: The installation of six boards around the lake which educate the community on why they shouldn’t be feeding the ducks.
Cllr Chichester-Miles said: “Advice received from the royal parks agency and the RSPCA concludes that feeding certain foods like bread is not only harmful to the duck’s digestive system but interferes with normal migratory patterns leading to ducks becoming reliant on feeding rather than migrating to warmer climbs.”