A month after threatening the federal government with legal action over the Purple Line light rail, an environmental group and many of the same Chevy Chase residents have done the same to the state of Maryland.

The Center for Sustainable Economy, Friends of the Capital Crescent Trail, and 16 individuals including a member of the Town of Chevy Chase Council have filed a Notice of Intent to sue state agencies for what the group says is the state’s violation of its own endangered species law.

At issue again is the existence of three types of amphipods, shrimp-like creatures known to live in the area’s streams that serve as an indicator of good water quality and healthy ecosystems. The group claims the state hasn’t adequately taken into account how construction and operation of the Purple Line would harm seven springs and seeps, plus two wetland areas in the path of the project or downstream.

“While this letter is a statutorily mandated precursor to filing a lawsuit, my clients are far more interested in the development and implementation of a conservation plan for protection of the endangered amphipods and their habitat than they are in litigation,” wrote Rockville-based attorney David Brown, who’s representing the group.

The notice letter cites research from American University biology professor David Culver, who the group claims has found evidence that the shrimp-like critters live in stream areas that would be directly affected — and perhaps wiped out — by construction of the 16-mile light rail through Chevy Chase.

The Friends of the Capital Crescent Trail hired Culver to conduct surveying for amphipods with a $15,000 grant from the Town of Chevy Chase, which is officially opposed to the Purple Line.

Culver is scheduled to go back out to the streams in the fall to survey for the creatures.

Also in the notice letter is a second expert opinion from Dr. David Berg, a biology professor at Miami University of Ohio who specializes in freshwater invertebrates, including amphipods.

Maryland has formally listed the Hay’s Spring and Kenk’s amphipods as endangered. The Kenk’s amphipod is still only a candidate for endangered species under federal law.

Not included in the notice letter to the state (see PDF below) is the Center for Biological Diversity, a major national organization that boasts 775,000 members that is a part of the complaint against the federal government.

The Center for Biological Diversity drew criticism from some Purple Line supporters, who said they were surprised to see such a major environmental organization opposed to a major transit project.

Also on Thursday, Town of Chevy Chase resident Christine Real de Azua urged the Planning Board to let developers in Chevy Chase Lake know that they should be responsible for protecting the amphipods, or face legal action.

The Board on Thursday approved the sketch plan for a 392 apartment and townhouse units on Chevy Chase Lake Drive, on the existing site of a series of two-story garden apartments.

While environmental steps aren’t ironed out in the sketch plan stage of the approval process, Real de Azua said planners should let the developer know of the amphipod issue. Planners have already told the developer that some efforts might need to be taken to protect a local population of herons:

But additional adjustments may be needed for amphipod protection, and traditional “rip-rap” rock and wire, or other bank stabilization may destroy stream bank seeps that are amphipod habitat. In short, the appropriate steps to protect the amphipods have yet to be determined. It is therefore important that the applicant be made aware through this Sketch Plan review process that the current proposed scale and configuration of this project is subordinate to the protection of all Endangered or otherwise protected species threatened by the project, not just the Yellow-Crowned Night Heron.

In the notice letter, the group said the specific locations of the at-risk seeps and springs found by Culver were redacted “out of concern for the integrity of the amphipod habitat.”

Residents part of the notice letter include Real de Azua, environmental attorney John Fitzgerald and Town of Chevy Chase Councilmember John Bickerman.

PDF: Notice of Violation – Endangered Species Act

Photos via Brett Hartl/Center for Biological Diversity