The High Line Canal (HLC) is a man-made waterway, used for

irrigation Irrigation (also referred to as watering of plants) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has bee ...

and recreation, that serves the Denver-Aurora metropolitan area. It begins at a

diversion dam A diversion dam is a dam that diverts all or a portion of the flow of a river from its natural course. Diversion dams do not generally impound water in a reservoir; instead, the water is diverted into an artificial water course or canal, which ...

on the

South Platte River The South Platte River is one of the two principal tributaries of the Platte River. Flowing through the U.S. states of Colorado and Nebraska, it is itself a major river of the American Midwestern United States, Midwest and the American Sou ...

, some above the mouth of

Waterton Canyon The Platte Canyon is a deep, narrow, scenic gorge on the South Platte River in the Rocky Mountains of Colorado. The canyon is southwest of Denver, Colorado, Denver in Park County The canyon is at the entrance to the mountains, where the South P ...

. From its headgate, the HLC runs generally northeast for (historically 71 miles), passing through

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Arapahoe The Arapaho ( ; , ) are a Native American people historically living on the plains of Colorado and Wyoming. They were close allies of the Cheyenne tribe and loosely aligned with the Lakota and Dakota. By the 1850s, Arapaho bands formed two ...

Denver Denver ( ) is a List of municipalities in Colorado#Consolidated city and county, consolidated city and county, the List of capitals in the United States, capital and List of municipalities in Colorado, most populous city of the U.S. state of ...

, and

Adams Adams may refer to: * For persons, see Adams (surname) Places United States *Adams, California *Adams, California, former name of Corte Madera, California * Adams, Decatur County, Indiana *Adams, Kentucky *Adams, Massachusetts, a New England to ...

Counties.Denver Water: High Line Canal
, accessed 09/23/2011.

Origin of the name

The High Line Canal is not the only one so named. Others in Colorado include the Farmer's High Line (which flows from Golden passing through

Westminster Westminster is the main settlement of the City of Westminster in Central London, Central London, England. It extends from the River Thames to Oxford Street and has many famous landmarks, including the Palace of Westminster, Buckingham Palace, ...

and Thornton); the Government High Line (which irrigates Grand Junction and the surrounding Grand Valley); and the Rocky Ford High Line (which irrigates land in the

Arkansas River The Arkansas River is a major tributary of the Mississippi River. It generally flows to the east and southeast as it traverses the U.S. states of Colorado, Kansas, Oklahoma, and Arkansas. The river's source basin lies in Colorado, specifically ...

Valley around Boone, Fowler, Manzanola, and Rocky Ford). Elsewhere in Colorado and in other western states, there are a number of additional canals named "High Line" or "Highline". High Line canals are named after the engineering principle by which they are designed.High Line Canal: Meandering Through Time. A Historical Trail Guide. By Dr. David Skari. Copyright 2003 David Skari. Printed by C&M Press, 4825 Nome St. Denver, Colorado 80239. The "high line principle" calls for a canal to follow the contours of the

terrain Terrain (), alternatively relief or topographical relief, is the dimension and shape of a given surface of land. In physical geography, terrain is the lay of the land. This is usually expressed in terms of the elevation, slope, and orientati ...

, with a minimal drop in elevation per mile along its course. Thus the canal follows the line of highest possible elevation that allows its flow to be driven by gravity (so that neither pumping nor electricity is required for transporting the water). As a result, High Line canals typically have many twists and turns as they maintain elevation by traversing natural valleys first in an upstream direction, then back down the opposite side, then around dividing ridges, and so on.

Developmental struggles

The company originally intended to place about 50,000 acres under cultivation, but it had difficulty securing sufficient water because earlier ditches held irrigation rights based on prior claims. Court cases regarding water rights dragged on for years. Because the High Line Canal's water rights were junior to 74 other canals in the South Platte watershed, it was frequently dry. Although the agricultural development that the HLC was meant to spawn never fully materialized, the canal nevertheless nourished the growth of both Denver and its eastern suburb,

Aurora An aurora ( aurorae or auroras), also commonly known as the northern lights (aurora borealis) or southern lights (aurora australis), is a natural light display in Earth's sky, predominantly observed in high-latitude regions (around the Arc ...

. In 1924,

Denver Water Denver Water is a water utility that operates as a Government agency, public agency serving the City and County of Denver, Colorado, and a portion of its surrounding suburbs. Established in 1918, the utility is funded by water rates and new tap ...

took over the canal.

Irrigation

The HLC was designed to carry nearly three-quarters of a billion gallons of water per day, but actually averages only 71 million gallons. The canal today has a water capacity of . When the

Rocky Mountain Arsenal The Rocky Mountain Arsenal was a United States chemical weapons manufacturing center located in the Denver Metropolitan Area in Commerce City, Colorado. The site was completed December 1942, operated by the United States Army throughout the ...

was built in 1942, a lateral was built off the HLC (at about mile 64) in order to supply water to the chemical weapons manufacturing center, and until about 2008, the

Rocky Mountain Arsenal National Wildlife Refuge The Rocky Mountain Arsenal National Wildlife Refuge is a National Wildlife Refuge located adjacent to Denver and Commerce City, Colorado, in the United States. It is approximately northeast of downtown Denver. The refuge is on the grounds of ...

was the furthest-downstream customer that was still taking water delivery via the HLC. However, the canal does not provide a very efficient method of delivering water; Denver Water estimates 60% to 80% of water in the canal is lost to seepage or evaporation. As a result, the Arsenal is now provided with recycled water instead of canal water, and as of 2011, the HLC's last customer is Fairmount Cemetery (at about mile 48). However, Denver Water still occasionally sends water further downstream, in order to water the trees that line the canal's bank. Denver Water has vacated the HLC downstream from mile 66.3 in Green Valley Ranch, and today there is very little visible evidence of the additional five miles that historically extended beyond that point.

Recreation and ownership

Although the HLC was originally built for the purpose of irrigation, today it is better known to Colorado residents as a source of recreation. For just over a century, the canal itself (and the water flowing through it) was owned by Denver Water, but in 2024 Denver Water transferred ownership of a 45-mile segment of the HLC to Arapahoe County, with a conservation easement held by the High Line Canal Conservancy. The adjoining maintenance road was entirely closed to the public until 1970.Guide to the High Line Canal Trail. Richard H. Johnson, ed. Published by Denver Water Community Relations Office, 1999. Today it remains closed to all unauthorized motor vehicles, but approximately of the road have been improved for use as a recreational trail open to non-motorized users. Designated a National Landmark Trail, it is a popular destination for Denver's outdoor enthusiasts and is open all year to hikers, bikers, joggers, and (along some segments) equestrians. The High Line Canal Trail is shaded for much of its length by mature cottonwood trees, and the surface of the pathway ranges from hard-packed dirt to concrete. Five agencies have recreational agreements to maintain sections of the trails: In January 2009,

The Trust for Public Land The Trust for Public Land is a U.S. nonprofit organization with a mission to "create parks and protect land for people, ensuring healthy, livable communities for generations to come". Since its founding in 1972, the Trust for Public Land has compl ...

helped place a conservation easement on of land adjacent to the popular High Line Canal Trail. The HLC supplies water to Buell Lake in Cherry Hills Village.

Wildlife

Deer, ducks, geese, turtles, hawks, herons, pelicans, raccoon, fox, coyotes, mountain lions,Second Sighting of Mountain Lion Reported on Highline Canal (Colorado Division of Wildlife press release, October 28, 1999)
/ref> and various other animals have been spotted on or around the canal and surrounding trails.

References

External links

Denver Water: High Line Canal (official)Denver Water: High Line Canal (map)Douglas County: Open Space, High Line Canal Regional TrailTrails.com summary of Highline Canal TrailCity of Littleton: Irrigation ProjectsDetailed interactive map showing trail conditions, milepost locations, photos, etc.
*

Historic American Engineering Record Heritage Documentation Programs (HDP) is a division of the U.S. National Park Service (NPS). It administers three programs established to document historic places in the United States: Historic American Buildings Survey (HABS), Historic American E ...

(HAER) documentation: ** ** ** {{Coord, 39.48294, -105.11558, format=dms, display=inline, title, type:river_region:US-CO Protected areas of Douglas County, Colorado Geography of Aurora, Colorado Geography of Denver Parks in Colorado Canals in Colorado Irrigation canals Greenways Historic American Engineering Record in Colorado National Recreation Trails in Colorado Irrigation in the United States Protected areas of Adams County, Colorado Protected areas of Arapahoe County, Colorado Protected areas of Denver Canals opened in 1883 Transportation in Adams County, Colorado Buildings and structures in Adams County, Colorado Transportation buildings and structures in Arapahoe County, Colorado Transportation buildings and structures in Denver Transportation buildings and structures in Douglas County, Colorado