A REPI + National Park Service land conservation initiative
The rivers and trails of the Lewis & Clark corridor double as the encroachment buffer for twelve military installations. That overlap unlocks federal conservation funding: REPI and RARI buy easements and land from willing sellers, keep working lands working, and turn protected ground into parks, water trails, and public access.
Why this corridor
Along the Lewis & Clark National Historic Trail sit a dozen military installations. The rivers and trails that carry the public also form the buffer that protects each installation’s mission. That overlap is the opportunity: the same acre can serve readiness, conservation, and recreation at once.
REPI and RARI exist for exactly this ground. REPI (Readiness and Environmental Protection Integration) funds conservation easements and land purchases from willing sellers, cost-shared with land trusts and states. RARI (the Readiness and Recreation Initiative) layers Land and Water Conservation Fund dollars on top to build the public side: parks, trail connections, boat ramps, and river access on the land that protection keeps open. Two corridors already sit inside designated Sentinel Landscapes; the rest are candidates.
Terrain360’s continuous 360° imagery supports the case. It records baseline conditions and the public value of each reach in a form grant reviewers, partners, and the public can see. The model starts here and extends to every National Historic Trail in the system.
Conservation easements and willing-seller acquisitions keep farms, forests, and river bottoms open. Landowners stay on the land; incompatible development stays out of the buffer.
Protected ground becomes public benefit: trail connections, boat ramps, campsites, and future parks built through RARI and state partners on the land easements keep open.
Open land around an installation is an operational requirement. Every easement that blocks incompatible development protects training and readiness for the long term.
Land use improvements
An easement keeps land open; RARI and state partners build what makes it public. These are the improvement types the funding stack pays for on protected ground.
Acquired parcels with high public value become new county, state, or trail-managed parkland.
Boat ramps, carry-down launches, and riverside campsites that turn a protected reach into a usable water trail.
Easement corridors close the gaps between existing public lands, linking trail segments that dead-end today.
Walk-in access agreements on easement land keep working farms and ranches open to sportsmen.
Specific sites are identified with installation, state, tribal, and land-trust partners. The corridor inventories below and the corridor maps are the starting list.
Who this serves
Conservation here is not a trade-off. The same protected acre serves the public that recreates on it, the landowner who keeps working it, and the installation and Trail office responsible for what surrounds it.
The public
Easements keep the corridor’s farms and forests undeveloped, and RARI builds the public side: trail connections, boat ramps, campsites, and future parks. The public gains permanent access to a corridor that today survives parcel by parcel.
Landowners & communities
Every acre moves by choice. Conservation easements compensate landowners for keeping farms, ranches, and timberland working while ruling out the subdivision that would close the corridor. Towns keep their tax base, their views, and their river.
Installations & the NPS
Open land around a base is an operational requirement, and the National Park Service stewards the Trail that threads through it. The same protected ground serves encroachment management, habitat, and the country’s longest National Historic Trail.
The recreation economy
The 2024 LECL Economic Impact Study, commissioned by the National Park Service and the Lewis & Clark Trust, documented the visitor economy across five Lewis & Clark Trail sites. Protected corridors at the twelve installations feed directly into that visitor flow.
Read the LECL Economic Impact Study →Sharp, Maples, Bogucki, Hicks (2024). IMPLAN Type SAM multipliers, five-site aggregate.
The corridor
Installation footprints and their REPI buffer corridors along the Lewis & Clark Trail. Click a marker for the corridor page.
The twelve installations
Each installation has its own LCNHT tie, its own access regime, and its own mix of rivers, trails, and public access sites. Click a card to explore the corridor.
Montana
Gates of the Mountains, LCNHT core
"Gates of the Mountains", named by Lewis, July 19, 1805.
Montana
Upper Missouri, LCNHT core
The Great Falls portage, 18 miles that nearly ended the expedition.
Indiana
Southern Indiana, near-corridor
Indiana's deepest OHV systems, near-corridor to the Trail.
Washington
Spokane River, return route
The Spokane River, L&C's return route, 1806.
Washington
Pacific terminus, LCNHT
Cape Disappointment, Pacific Ocean in view, November 1805.
North Dakota
Fort Mandan country
Sacagawea joined the Corps at Knife River, November 1804.
Washington
Columbia / Snake confluence
Sacajawea State Park, the 1805 Snake/Columbia camp.
Idaho
Snake River Plain
The densest raptor nesting concentration in North America.
Missouri
St. Joseph reach, Lower Missouri
Independence Creek — named by the Corps on July 4, 1804.
Nebraska
Council Bluff, Lower Missouri
The first formal council with the Otoe, August 3, 1804.
Kansas
Lower Missouri, Kaw confluence
The Corps camped at Kaw Point, June 26, 1804.
Methodology
Both-bank river capture by boat, trail capture by backpack or UTV, and fixed 360° nodes at access sites. Each corridor's imagery records the recreation and buffer lands an easement would protect, and the dataset goes to the installation INRMP team and the NPS for reuse.
Both-bank river capture and trail capture record the lands an easement would protect, reach by reach.
Fixed 360° nodes at boat ramps, trailheads, and interpretive sites inventory what the public stands to gain.
Geo-referenced panoramas and GPS tracks go to each installation’s INRMP team and the NPS Trail Office.
The same record supports REPI reporting, RARI applications, and Sentinel Landscape nominations.
Partners
Lewis & Clark NHT Office
lewisandclarktrust.org
Readiness & Environmental Protection Integration
Per-corridor coalition - TBD
Future phases
One federally administered National Historic Trail, twelve installations, four funding frameworks. The same conservation model applies to every other National Historic Trail in the system, wherever trail lands and installation buffers overlap.
How Sentinel Landscapes expand →Candidate corridors
NSA Mid-South, Arnold AFB, McGhee Tyson ANGB, Memphis ANGB, Berry Field ANGB. Mississippi River, Tennessee River, and Cumberland Plateau corridors.
F.E. Warren AFB (WY), Camp Guernsey (WY), Hill AFB (UT), Mountain Home AFB (ID). North Platte, Sweetwater, and Snake River corridors.
Fort Riley (KS), Fort Leavenworth (KS), Cannon AFB (NM), Holloman AFB (NM), Kirtland AFB (NM), White Sands MR. Arkansas, Cimarron, and Rio Grande corridors.
Maxwell AFB (AL), Gunter Annex, Fort Novosel. Alabama River and civil-rights interpretive corridor.
Get involved
INRMP managers, REPI coordinators, NPS Trail Office staff, and land-trust / state / tribal partners: tell us what would make the corridor protection case useful at your installation.
Your message reaches Larry Calhoun (NPS Lewis & Clark NHT) and Ryan Abrahamsen (Terrain360). Expect a reply within a few business days.
Read the methodology →