Public Notice: Water Quality Certification of Repair Diversion Structure at Lake Sequalitchew Project in Washington

Please email your comments to the EPA Region 10 Wetlands and Oceans Section at [email protected] with a copy to Sarah Burgess ([email protected]).

If you are unable to submit comments by email, or if you need other assistance, please contact Sarah Burgess at 206-553-6698.

Do not submit any information you consider to be confidential business information. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make.

On April 21, 2023, EPA received a request from the Environmental Division of the Directorate for Public Works at Joint Base Lewis-McChord for a Clean Water Act Section 401 Water Quality Certification for the Repair Diversion Structure at Lake Sequalitchew Project [Seattle District Corps of Engineer’s permit project number NWS-2022-900, applied for under Nationwide Permit 43 for stormwater management facilities].

Section 401(a)(1) of the Clean Water Act requires applicants for federal permits and licenses that may result in discharges into waters of the United States to obtain certification that the discharge will comply with applicable provisions of the Clean Water Act. Where no state agency or tribe has authority to give such certification, EPA is the certifying authority.

In this case, the project occurs on Joint Base Lewis-McChord which is a land of exclusive federal jurisdiction. Therefore, EPA is making the certification decision for discharges that may result from the proposed project.

EPA is requesting comments on its Clean Water Act Section 401 water quality certification for the proposed project.

As a certifying authority, EPA must decide whether to:

The proposed Repair Diversion Structure at Lake Sequalitchew Project is located on Joint Base Lewis-McChord (JBLM) near the town of Dupont, Washington (latitude 47.112, longitude -112.617).

The project purpose is to repair the existing outlet diversion weir and canal-creek cross-over culverts downstream of the Lake Sequalitchew outlet to restore the normal storm flows to Sequalitchew Creek while diverting higher storm flows to the north JBLM stormwater canal.

Currently, the canal-creek cross over culverts are not functioning as intended and direct most of the groundwater and stormwater in-flow from Lake Sequalitchew and Hammer Marsh into the JBLM stormwater canal. The project will restore the original intent of the outlet diversion weir to handle only overflow from the lake and marsh, with normal base and seasonal flows directed to Sequalitchew Creek.

The proposed action is to implement a new outlet diversion weir system at the tailwater of the triple reinforced concrete box bridge structure to restore stream flow to Sequalitchew Creek, regulate the lake level, and to prevent backwater flow from entering the Sequalitchew springs water distribution system. The canal-creek cross-culvert pipe is to be removed, and hydraulic connectivity re-established from the canal-marsh system to the creek with a new connecting channel.

Repairs will include removal of:

Repairs will also include construction of:

These activities will impact 0.14 acres/400 linear feet of Waters of the U.S.

Project impacts will be minimized by: