A master's project which identified the best system to clear algae from a reservoir aids the 'Watermen' in BBC series.

The final episode of the BBC 2 Watermen programme featured an innovative reservoir mixing system imported from Australia to solve algal bloom problems in Heaton Park reservoir, Manchester. 

The reservoir was needed as an alternative source of water for two million people whilst the 90 km long Hawswater aqueduct was being overhauled. 

Failure to remove the algae at Heaton Park would have jeopardised the whole multi million pound aqueduct refurbishment programme, being carried out by the water supply company United Utilities

United Utilities wanted to know the best way to remove the algae from the reservoir.  So they asked Lancaster Environment Centre for help. Steven Jackson, studying for an MSc Sustainable Water Management, took on this task as his master’s project.   

Finding the solution

Working under the supervision of Andy Benn from United Utilities and Dr Nick Chappell from Lancaster Environment Centre, Steven evaluated the different options. He identified the WEARS ResMixTM system as the most effective and cost efficient solution for United Utilities.  

This ResMix works by mixing the water in the reservoir so the algae filled water at the top moves to the bottom, depriving the algae of the light it needs to flourish.  

During the programme BBC viewers saw the ResMix system being installed in the reservoir and tests being done four weeks later to find out how well the new system was working.

Would it work in practice?

The tests were carried out by Lisa White of Xylem Analytics UK, another graduate of Lancaster Environment Centre. Lisa used an innovative autonomous underwater vehicle - the Xylem Ecomapper - to measure algal bloom levels in the entire reservoir.  The results showed a 99% decline in algae levels, enabling the reservoir to be used to supply water, and the aqueduct overhaul programme to go ahead.

Lisa is currently working with Nick using two innovative sensors - the EXO2 chlorophyll sensors and the S::CAN carbon sensors - on the NERC DURESS project. The DURESS project seeks to quantify the economic returns for water companies coming from stream biofilms ‘cleaning’ upland water resources.  

Meanwhile Steven has graduated and immediately started work as a Project Manager with Kelda Water Services.