## Facts

- Dyke Marsh is a wetland along the Potomac River near Alexandria, Virginia; a private developer owned a tract within the marsh and planned the Potomac Greens mixed-use development nearby.
- In 1970–1971, the developer and the National Park Service (NPS) entered an exchange agreement: the developer conveyed its Dyke Marsh tract to the United States, and NPS agreed to grant an easement to build an interchange on the George Washington Memorial Parkway to access Potomac Greens.
- The agreement conditioned construction on design approval by NPS, the National Capital Planning Commission (NCPC), and the Commission of Fine Arts, and specified core interchange features limiting agency discretion.
- The developer submitted plans in 1975; NPS required additional environmental assessment in 1976 due to changed conditions and traffic.
- NPS approved an interchange design in 1981; NCPC approved in 1983; NPS issued an easement deed in 1984 to the developer’s successor interests.
- By the time suit was filed, no construction had begun on the interchange or the development, and only limited project expenditures had been incurred.
- In 1986, an environmental group sued to invalidate (1) the exchange agreement and (2) the 1981/1983 interchange design approvals under NEPA and other legal theories.
- The district court dismissed: it treated the design-approval challenges as moot and barred the exchange-agreement challenge under laches; a prior appellate order summarily affirmed mootness as to the NEPA claim only.

## Issues

1. Whether claims (other than the NEPA claim) seeking to invalidate interchange design approvals were moot.
2. Whether laches barred the challenge to the 1970–1971 exchange agreement.

## Decision

- Vacated the district court’s mootness ruling to the extent it dismissed counts other than the NEPA claim.
- Left undisturbed the prior disposition that the NEPA claim was moot.
- Reversed the district court’s application of laches to bar the challenge to the exchange agreement.
- Remanded for further proceedings on the remaining claims.

## Legal Principles

- A claim is moot only if the court cannot grant any effective relief; absence of construction and limited reliance expenditures may support a finding that relief remains available.
- Mootness analysis is claim-specific; the mootness of a NEPA theory does not automatically moot distinct, non-NEPA theories seeking related relief.
- Laches requires both unreasonable delay and concrete prejudice; substantial, project-specific reliance and changed position are central to the prejudice inquiry.
- Courts apply laches cautiously where plaintiffs seek judicial review of governmental action affecting public resources and alleged statutory compliance, especially when implementation remains largely unexecuted.

## Conclusion

The D.C. Circuit held that, apart from the already-dismissed NEPA claim, the challenge to the interchange approvals was not moot because effective relief remained possible, and it rejected laches as a bar to the exchange-agreement challenge on the record presented, remanding for merits proceedings.


Daingerfield Island Protective Soc'y v. Lujan, 920 F.2d 32 (D.C. Cir. 1990)