Sewage Treatment Regulations Specifying a sewage treatment plant or septic tank can depend on many factors such as soil conditions, effluent factors, population served and council and environment agency regulations. In all cases advice should be sought from the local authority Environmental Health Department. It may also be necessary to consult: Reference should also be made to the following guidance notes Will you need planning permission? You should contact your local authority to determine whether or not planning permission is required before you begin the project. Quite often, in new build situations particularly, this approval will form part of the overall permission but be sure to have this clarified in every case. Consent to Discharge Where effluent will be discharged to a watercourse and depending on the volume, consent must be granted by your local environment agency before you begin your installation. If you do not obtain such a “licence” you may be liable to prosecution. Your agency will be happy to advise you on the level of effluent treatment required in the area and this information will help you determine which type of sewage treatment plant should be installed. You will then be required to complete and submit a Consent to Discharge application form including a fee to the appropriate agency. Consent to discharge criteria is normally expressed in permitted milligrams per litre for the following factors: