Lagerman Agricultural Preserve
Lagerman Reservoir

Lagerman Agricultural Preserve

A trail detour will be in place starting Oct. 18. Crews will install culverts under the Open Sky Loop near the trailhead. Trail users will be detoured along Prospect Rd. during active construction. When possible, the trail will be open Friday – Sunday. Construction is expected to be completed by Nov. 11, depending on weather. Trail Detour Map

Lagerman Agricultural Preserve is a place enjoyed by birders, boaters, picnickers, bikers, runners, and dog-walkers. Lagerman Reservoir has something for the entire family. There is a picnic site, wetlands, and a seasonal osprey nest.

Lagerman TrailHiking Allowed Dogs Allowed Bikes Allowed E-bikes Allowed Horses Allowed
1.6 miles – Easy
Open Sky LoopHiking Allowed Dogs Allowed Bikes Allowed E-bikes Allowed Horses Allowed
4.9 miles – Easy

Rules & Regulations

Day Use Only
Pets On Leash
Bikes On Designated Trails Only
No Swimming
No Hunting/Firearms
No Camping

All Parks & Open Space Rules & Regulations

Keep In Mind

  • From April 1 – Aug. 31, the western end of the reservoir is closed for nesting birds.
  • Swimming and wading are prohibited.
  • Fishing is not recommended at Lagerman Reservoir. There was a complete fish die-off in late 2018 due to poor oxygen levels. Staff are investigating ways to improve water quality and restore fishing in the future.

Trailhead Amenities

24 car parking spots
2 ADA parking spots (1 van accessible)
Several picnic tables
50 person group shelter
5 horse trailer parking spots

See Photos

Boating Regulations

What’s Allowed

  • Boats, canoes, kayaks, stand up paddle boards (SUP), and inflatables where you sit out of the water are allowed.
  • Sailboards and sailboats are prohibited.

Personal Flotation Devices (PFD)

  • A USCG approved Type I, II, or III PFD is required for each person on board.
  • PFDs should be readily accessible.
  • Boats 16 feet in length or longer require one additional Type IV PDF which should be readily accessible.
  • Children 12 years old or younger are required to wear a PFD.
  • All PFDs should be appropriately sized and in good condition.

Motorized Boats

  • Motorized boats require a current registration on board.
  • Fire extinguisher is required on board for permanently installed fuel tanks.
  • Motorized boats with electric or gasoline powered motors of 8 horsepower or less are allowed.
  • Any motorized boat with a motor larger than 8 horsepower shall have that motor’s propeller lifted out of the water at all times.
  • No-wake speed only.

Wetland habitats, nestled within the surrounding Great Plains, support aquatic plant and animal life and serve to lure in large numbers of migrating bird species. With grasses, wildflowers and trees surrounding the wetlands, these areas are biologically diverse both in and out of the water.


  • Black-tailed prairie dog
  • Coyote
  • Desert cottontail
  • Little brown bat
  • Raccoon
  • Red fox
  • Western harvest mouse


  • American avocet
  • American crow
  • American kestrel
  • American widgeon
  • American white pelican
  • Bald eagle
  • Barn swallow
  • Black-billed magpie
  • Black-crowned night heron
  • Canada goose
  • Common raven
  • Double-crested cormorant
  • Great blue heron
  • Great egret
  • Great horned owl
  • Killdeer
  • Mallard
  • Mourning dove
  • Osprey
  • Pied-billed grebe
  • Red-tailed hawk
  • Red-winged blackbird
  • Ring-billed gull
  • Rock dove
  • Snowy egret
  • Song sparrow
  • Swainson’s hawk
  • Western grebe
  • Western kingbird
  • Western meadowlark

Amphibians & Reptiles

  • Western painted turtle
  • Bullsnake
  • Western plains garter snake


  • Black crappie
  • Bluegill
  • Channel catfish
  • Gizzard shad
  • Largemouth bass
  • Tiger muskie
  • Walleye

Coming Soon

Swedish Heritage

Reverend Frederick Lagerman was pastor of the 1878 “Swedish Evangelical Congregation of Ryssby, Boulder County, Colorado” Lutheran Church. The church congregation purchased 160 acres of land near the current reservoir as a prastgard, or pastor’s garden. As was Swedish custom, church members farmed the land, giving the bounty to the pastor as his salary. The irrigation reservoir for the prastgard was listed on state records as Lagerman Reservoir.

Contact Us

Parks & Open Space

Staff Directory
Submit a Question

Office Location
5201 St. Vrain Rd.
Longmont, CO 80503
Map & Directions
Office Hours: 8 a.m. - 4:30 p.m. M-F

Parks are open sunrise to sunset

Connect With Us