Sch 1 para 1 Water
(1) Any physical infrastructure used, or intended for use, in the production, transport or distribution of water (including disposal or treatment of waste water and sewage, and drainage systems) which is— (a) a pipe with an internal diameter less than 225 millimetres; (b) a sewer downstream of a combined storm overflow and is within 100 metres of that overflow; (c) a sewer in an area of known inundation or hydraulic incapacity; (d) a sewer in respect of which, if cables were to be installed as part of a high-speed electronic communications network, they would need to be installed in the invert; (e) a sewer in respect of which the mandatory maintenance work required is greater than may normally be expected for a sewer; or (f) equipment used to pump sewage. (2) “Mandatory maintenance work” is the work done by, or on behalf of, the undertaking responsible for the sewer in consequence of any requirement to maintain the sewer imposed on the undertaking under the law of the United Kingdom, or the law of any part of the United Kingdom.