Wealden District Council > Environment and Pollution > Pollution > Guidance for developers and consultants > Provision for drainage Listen Provision for drainage Wealden is a large rural district and new developments may not be able to connect to the mains sewer. In such instances, for small developments, a mini waste water treatment plant may be required with discharge to a local water course. This must be agreed with the Environment Agency (external link) and the relevant permissions or permits granted. In circumstances where it might be possible to connect a new development to the mains sewer it is absolutely essential that this is discussed with Southern Water (external link) before making a planning application. This is because some treatment plants operated by Southern Water are operating at capacity and Southern Water may reject such an application. It cannot be assumed that a new housing development will be allowed to connect to the main sewer and a private treatment plant for such a development might need to be considered.