WS 25: Approval of Treatment Facility Modification

Approval to alter a water treatment facility

MassDEP Drinking Water Program

The Details of WS 25: Approval of Treatment Facility Modification

What you need for WS 25: Approval of Treatment Facility Modification

This approval serves to protect the public's health and welfare by insuring that minimum drinking water requirements are met in the modification of a drinking water facility. Legislative authority is stated in MGL Chapter 111, section 160A. Regulatory authority is stated in 310 CMR 22.04 of the Drinking Water Regulations.

Public water suppliers or their representatives must apply if they want approval for modification of their water treatment facility. 

If the water supplier or their representative apply for this approval it may be necessary to apply for other water treatment approvals WS 23 or WS 24.

Note: Approvals of this type may require MEPA review. Please carefully examine 301 CMR 11.00, the MEPA Regulations, to determine if your project exceeds the MEPA review thresholds, or for more information contact the MEPA Unit of the Executive Office of Environmental Affairs (100 Cambridge Street, Boston, MA 02202; 617-727- 5830). MassDEP cannot begin technical review of the application until the MEPA process has been completed, unless otherwise agreed to in writing. Copies of MEPA filings (with reference to any applicable Transmittal numbers) should be sent to the appropriate program offices in Boston and the MEPA Coordinator in the appropriate Regional Office.

Note: These additional requirements are intended to serve as a guide to the applicant. It does not necessarily include all additional requirements.

How to apply WS 25: Approval of Treatment Facility Modification

See details below.

Next steps for WS 25: Approval of Treatment Facility Modification

  1. Review the Instructions

    Guidance on how to prepare your application, including a completeness checklist.

  2. Complete the Application Form

    You may fill out and save the Microsoft Word form on your computer. The PDF version has to be printed out and completed by hand.

  3. Obtain a Transmittal Form and Number

    A unique Transmittal Number is needed for each application you submit to MassDEP.

  4. Lookup the Permit Application Fee

  5. Mail Your Application and Fee Payment

    Submit your application fee payment and a copy of your Transmittal Form to:

    Department of Environmental Protection
    PO Box 4062
    Boston, MA 02211

    Submit your completed, signed application and your original Transmittal Form to the appropriate MassDEP Regional Office (see listing below).

Contact for WS 25: Approval of Treatment Facility Modification

MassDEP Boston
1 Winter Street, Boston, MA 02108