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Twin Lakes
Twin Lakes

Twin Lakes

This open space is a haven for wetland wildlife, a hidden gem in the heart of Gunbarrel area. Whether spending a lazy afternoon fishing or having an invigorating morning jog, community enjoyment runs high here.

East Twin Lakes TrailHiking Allowed Dogs Allowed Bikes Allowed E-bikes Allowed Horses Allowed
0.7 miles – Easy
Dogs must be on a leash
West Twin Lakes TrailHiking Allowed Dogs Allowed Bikes Allowed E-bikes Allowed Horses Allowed
0.7 miles – Easy
Dogs off leash allowed

Rules & Regulations

Day Use Only
Pets Allowed
Bikes On Designated Trails Only
No Swimming
No Boating
No Camping

All Parks & Open Space Rules & Regulations

Trailhead Amenities

On-street parking
Portable toilet available during summer months

See Photos

Keep in Mind

  • Dogs are allowed off leash on the West Lake Trail. They must be on leash everywhere else.
  • Fishing is allowed, however, the lakes are not stocked.
  • Wading and swimming are not allowed.
  • Regional trails and regional trail connectors are open to commuters 24 hours per day. Trailheads close at sunset and parking is not allowed between sunset and sunrise.

West Lake Maintenance Project

West Lake Maintenance Project Map
  • The West Lake Trail will be closed Monday through Thursday for several months for a maintenance project.
  • The project will address the severe erosion that is extensively undercutting the embankment of the lake, jeopardizing user safety.
  • Riprap armoring will be added along the north shore to delay the loss of the cottonwoods that flank that embankment. Additional armoring will be added to the south shore.
  • Fencing will be added to protect visitors and dogs from accessing angular riprap armoring.
  • Formal entryways will be installed to improve user safety and direct user traffic to boulder steps into the water’s edge.

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.


  • Coyote
  • Eastern cottontail
  • Fox squirrel
  • Little brown bat
  • Raccoon
  • Red fox
  • Striped skunk


  • American avocet
  • American coot
  • American crow
  • American goldfinch
  • American kestrel
  • American robin
  • American widgeon
  • Belted kingfisher
  • Canada goose
  • Common grackle
  • Common raven
  • Downy woodpecker
  • Black-billed magpie
  • Black-capped chickadee
  • Bullock’s Oriole
  • Double-crested cormorant
  • Great blue heron
  • Great Horned Owl
  • Killdeer
  • Mallard
  • Mourning dove
  • Red-tailed hawk
  • Red-winged blackbird
  • Tree swallow
  • Violet-green swallow
  • Yellow-rumped warbler
  • Yellow Warbler

Amphibians & Reptiles

  • Bullsnake
  • Garter snake
  • Snapping turtle

Shrubs & Trees

  • American plum (Prunus americana)
  • Boxelder (Acer negundo)
  • Chokecherry (Prunus virginiana)
  • Coyote willow (Salix exigua)
  • Peachleaf willow (Salix amygdaloides)
  • Plains cottonwood (Populus deltoides var. monilifera)
  • Red-berried elder (Sambucas racemosa)
  • Smooth Sumac (Rhus glabra)
  • Trembling aspen (Populus tremuloides)
  • Wild licorice (Glycyrrhiza lepidota)

Grasses, Sedges, Cattails & Ferns

  • Broad-leaved cattail (Typha latifolia)
  • Narrow-leaved cattail (Typha angustifolia)
  • Nodding bulrush (Scirpus pendulus)
  • Smooth horsetail (Equisetum laevigatum)

White Wildflowers

  • Common lambsquarters (Chenopodium album)
  • Great Plains yucca (Yucca glauca)
  • Hemp dogbane (Apocynum cannabinum)
  • Riverbank grape (Vitis riparia)
  • Star-flowered lily-of-the-valley (Maianthemum stellatum)

Yellow Wildflowers

  • Common sunflower (Helianthus annuus)
  • Curlycup gumweed (Grindelia squarrosa)
  • Giant goldenrod (Solidago gigantea)
  • Golden currant (Ribes aureum)

Pink, Orange & Red Wildflowers

  • Desert paintbrush (Castilleja angustifolia)
  • Showy milkweed (Asclepias speciosa)
  • Swamp milkweed (Asclepias incarnata)
  • Velvetweed (Oenothera curtiflora)
  • Western snowberry (Symphoricarpos occidentalis)
  • Woods’ rose (Rosa woodsii)

Green Wildflowers

  • Giant ragweed (Ambrosia trifida)
  • Western ragweed (Ambrosia psilostachya)

Water Rights

Since 1910, the Boulder and Left Hand Ditch Company has operated the two lakes, which are reservoirs used to store water for agriculture. Boulder and Left Hand Ditch Company still owns the rights to the water and Boulder County owns the land surrounding them.

Growing Gunbarrel

In the 1960s, thanks to the nearby IBM plant and other commercial attractions, the Gunbarrel residential area grew up around the lakes. The lakes have been central to the Gunbarrel community from the beginning.

Contact Us

Parks & Open Space

Mon-Fri 8 a.m. – 4:30 p.m.
Office Location
5201 St. Vrain Rd.
Longmont, CO 80503
Map & Directions
Office Hours: Mon-Thu 8 a.m. – 4:30 p.m.
Friday by phone, email, or appointment only.
Parks are open sunrise to sunset

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