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Sustainable Water Management Initiative (SWMI)

January 1st, 2020



What is the Sustainable Water Management Initiative (SWMI)?

SWMI is a framework for permitting water supplies that intends to balance the needs of water for both human use and aquatic habitat protection. SWMI was developed by the Executive Office of Energy and Environmental Affairs (EEA) to address the long term sustainability of Massachusetts water resources. If your water supply is permitted through the Water Management Act (WMA) regulations, SWMI will affect you.

The goals of SWMI are to:

  • Provide predictable and science-based permitting;

  • Ensure sustainable use of water; and

  • Maintain healthy watersheds.

SWMI strives to meet these goals by:

  • Identifying a baseline for water withdrawals and evaluating increased withdrawals over this baseline in light of seasonal low flows in affected surface waters;

  • Minimizing impacts on stream flows through strategic water supply operation, demand management, and water use reductions; and

  • Mitigating for water withdrawals through measures that introduce water back into groundwater (such as wastewater returns, infiltration of stormwater), or measures that benefit aquatic habitat.



When Does SWMI Apply to Me?

The revised WMA regulations are expected to be promulgated by the end of the year. Once the regulations are in place, water suppliers will need to comply with SWMI provisions when their current WMA permits come up for renewal (see table below), or when they seek to increase their permitted withdrawal volume. Compliance with SWMI will require concerted planning that may require your community to go well beyond the documentation of water demand and how to supply it. It is not too soon to begin planning for your future permit renewals.

WMA Permit Renewals


Major Basins


South Coastal, Cape Cod


Boston Harbor, Taunton, Ipswich, Islands, Buzzards Bay, Concord, and Ten Mile


Deerfield, Housatonic, Farmington, and Westfield


Millers, Chicopee, Quinnebaug, and Connecticut


Nashua, French, Shawsheen, and Merrimack


Parker and Narragansett


Basins Previously Permitted that will be Adjusted at Next 5-Year Permit Review


Major Basin




North Coastal


Blackstone, Charles

All WMA permits within a major watershed basin expire and come up for renewal at the same time. The current proposed permit renewal schedule, by major basin, is provided in this table; however, this schedule is subject to change depending on the development of final WMA regulations.



What Will My Requirements Be Under SWMI?

Depending on your baseline, the size of your withdrawal request, and the streamflow criteria of your subbasins, your system will be placed into one of 3 permit review Tiers:

  • Tier 1 – No additional withdrawal request above baseline.

  • Tier 2 – Withdrawal request is above baseline, but the increase would not cause a change in streamflow criteria categories (GWC or BC) for the subbasin(s).

  • Tier 3 – Withdrawal request is above baseline, AND the increase would cause a change in streamflow criteria categories (GWC or BC) for the subbasin(s).

SWMI specifies WMA permit conditions for each of these Tiers. All permits (all Tiers) will be subject to standard WMA permit conditions that address the following:

  • Groundwater Supply Protection Requirements/Surface Water Supply Protection Requirements

  • Firm Yield Analysis for PWS Surface Water Supply

  • Wetlands and Vernal Pool Monitoring

  • Performance Standard for Residential Gallons Per Capita Day Water Use (RGPCD)

  • Performance Standard for Unaccounted for Water (UAW)

  • Seasonal Limits on Nonessential Outdoor Water Use

  • Water Conservation Requirements

  • Water Withdrawals that Exceed Baseline Withdrawal Volumes

In addition to the standard conditions, the pending regulations will impose other requirements intended to offset the surface water impacts associated with increased withdrawals. The requirements will likely include minimization requirements for systems that withdraw from subbasins with an August Net Groundwater Depletion (NGD) percentage of 25% or more, mitigation measures for systems that request withdrawal volumes over their baseline, and additional stream protection measures for those systems with Coldwater Fishery Resources (CFR) located within their subbasin(s).



How Can I Plan for SWMI?

There are things water suppliers can do now to get a "head start" on SWMI compliance and prepare for the pending regulations. CEI is encouraging PWSs who have WMA permits to begin building the foundation for their next permit renewal, and this groundwork can be initiated even before the final regulations are issued. Some steps that you can take now include the following:

  • Determine when your current permit is up for renewal;

  • Develop an action plan and schedule for undertaking the following steps and preparing the needed documentation for your next renewal application;

  • Develop an understanding of the Biological Categories (BCs), Groundwater Withdrawal Categories (GWCs), and August Net Groundwater Depletion (NGD) percentages that apply to the subbasins in which your withdrawal points are located;

  • Develop an estimate of your Baseline, as defined in the current SWMI Framework documentation;

  • Develop an estimate of the Groundwater Withdrawal that you will be requesting upon your next renewal;

  • Assess and document the water conservation efforts you currently implement;

  • Review and document your status with meeting 65 RGPCD and 10% unaccounted-for-water;

  • Understand how wastewater and stormwater are handled within your community, and whether and where these infrastructure systems recharge water to groundwater;

  • Develop an understanding of how dams are managed in your community, and who owns and maintains these facilities;

  • Develop an understanding of culvert crossings in your community, including scheduled repairs/replacements and potential habitat improvements;

  • Review your relationships with other town departments such as Planning, Engineering, DPWs, and Conservation Departments.  Successful compliance with the new SWMI WMA regulations will require you to work closely with these departments in a holistic approach to managing the water resources within your community;

  • Apply for a SWMI Grant to help identify or implement mitigation projects.



How Can CEI Help Me?

CEI can help you navigate the new regulations and identify how they will affect your next permit renewal. Specific areas might include:

  • Estimating your community's withdrawal baseline and determining the applicable Groundwater Withdrawal Category, Biological Category, and corresponding review Tier. 

  • Exploring how the standard conditions apply to your water supply and withdrawal requirements.

  • Assisting in planning for the implementation of required minimization and mitigation measures when you renew your permit. 

CEI has worked directly with the EEA and its partners to evaluate how SWMI will work once enacted into regulation. Our involvement in the SWMI pilot study, coupled with our long record of successful planning and engineering assistance to community water suppliers, enables us to serve as a valuable resource as you plan your water supply's future.


For more information, please contact Rebecca Balke, P.E., LEP at 800-725-2550 x308,  [email protected] 

Posted in the category About CEI.