Enhanced rapid gravity filtration and dissolved air flotation for pre-treatment of River Thames reservoir water

• Published in: RESERVOIR MANAGEMENT AND WATER SUPPLY--AN INTEGRATED SYSTEM Vol. 37; no. 2; pp. 35 - 42
• Main Authors: BAUER, M. J, BAYLEY, R, CHIPPS, M. J, EADES, A, SCRIVEN, R. J, RACHWAL, A. J
• Format: Conference Proceeding Journal Article
• Language: English
• Published: New York NY Pergamon Press 1998; Oxford IWA Publishing
• Subjects: Air; Algae; Anabaena; Aphanizomenon; Applied sciences; Blooms; Drinking water and swimming-pool water. Desalination; Exact sciences and technology; Filtration; Flotation; Freshwater; Gravitation; Gravity; Melosira; Modernization; Operational problems; Ozone; Pollution; Pretreatment; Reservoir management; Reservoirs; Rivers; Separation techniques; Tunnels; Wastewater treatment; Water purification; Water shortages; Water supply; Water treatment; Water treatment and pollution; England; United Kingdom; Great Britain; Europe; British Isles, England, Thames R; Drinking water treatment; Flotation; Filtration; Pretreatment; Artificial lake
• ISBN: 0080433804; 9780080433806
• ISSN: 0273-1223; 1996-9732
• DOI: 10.1016/S0273-1223(98)00007-9

Thames Water treats approximately 2800Ml/d of water originating mainly from the lowland rivers Thames and Lee for supply to over 7.3million customers, principally in the cities of London and Oxford. This paper reviews aspects of Thames Water's research, design and operating experiences of treating algal rich reservoir stored lowland water. Areas covered include experiences of optimising reservoir management, uprating and upgrading of rapid gravity filtration (RGF), standard co-current dissolved air flotation (DAF) and counter-current dissolved air flotation/filtration (COCO-DAFF®) to counter operational problems caused by seasonal blooms of filter blocking algae such as Melosira spp., Aphanizomenon spp. and Anabaena spp. A major programme of uprating and modernisation (inclusion of Advanced Water Treatment: GAC and ozone) of the major works is in progress which, together with the Thames Tunnel Ring Main, will meet London's water supply needs into the 21st Century.