Contaminated Land Find out if the property you are buying or selling is on contaminated land. Air quality in Colchester How we monitor air quality, air quality management areas and reports. Private water supplies and distribution Regulations for people who own or use a private water supply or a private distribution network. Mersea bathing water quality Current and previous year's water standards for Mersea bathing water. Drainage Report a blocked private sewer or arrange drains repairs. Asbestos How to remove and dispose of Asbestos safely. How to check your oil storage tank Advice on how to prevent oil spillage from your domestic oil storage tank. Japanese Knotweed Your legal responsibility for dealing with invasive plants and how to remove and dispose of them.