Richard Stenzel
The Grand River Ditch, hand-dug for its first 8 miles in the 1890s largely by immigrant laborers and extended through the 1930s, diverts water from headwaters streams of the Colorado River (named the Grand River until 1921) across the Continental Divide to the South Platte Basin. Water flows east to La Poudre Pass, then into Long Draw Reservoir where it is released into the Cache la Poudre River, ultimately reaching Water Supply and Storage Co. canals near Fort Collins.
Brandi Bracht-Flyr
The Early Era: Colorado’s First Transbasin Diversions
The Cameron Pass Ditch, an early trans-sub-basin diversion built by the Larimer County Ditch Company to move water from the North Platte Basin to the South Platte Basin, was completed in 1882. Just 3 feet wide and a half-mile long, the ditch transfers water from Michigan Creek, a tributary to the North Platte River, to the Cache la Poudre watershed.
In semi-arid Colorado, there has always been a need for water engineering to meet demands. The Ancient Puebloans of the Mesa Verde region built diversion ditches and reservoirs, as did Colorado’s early Spanish settlers hundreds of years later in the 1800s. Throughout the 19th century small irrigation ditches gave way to larger community ditches. By 1890, the South Platte River and its tributaries were so heavily appropriated by irrigators that junior water rights were often shut down by late summer because there was not enough water to serve all needs. Most of the Arkansas River bottomlands were also under irrigation, with canals undergoing expansion and new, longer ditches being built to reach as far east as Sugar City in Crowley County. The state’s population was 194,000; Denver was home to 35,000. At the time, there was still little development on the West Slope, so East Slope water users could secure senior water rights on the other side of the Continental Divide and channel it east to meet the needs of their growing populations and crops. Transbasin diversions and plans for diversions became the necessary solution to the puzzle of the East Slope’s water scarcity. The earliest transbasin diversions were constructed quickly and simply in response to water shortages. In 1882, the Larimer County Ditch Company became one of the first irrigation companies to pursue a transsub-basin diversion across a significant river basin boundary. The company built the Cameron Pass Ditch, which brought water from
1935 Northern Colorado Water Users Association forms to pursue Colorado-Big Thompson Project
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Michigan Creek in the North Platte Basin to the Cache la Poudre watershed in the South Platte Basin. The Cameron Pass Ditch was small by today’s standards, only 3 feet wide, 1 foot deep and a half-mile long. Other projects followed, including the well-known Grand River Ditch, where work began in 1894. The Grand River Ditch originated at the headwaters of the Colorado River, then called the Grand River, and delivered water to farms along the Poudre—making it the first transbasin diversion from the Colorado River mainstem. The Grand River Ditch was an engineering marvel at the time, with 8 miles of ditch built by hand across a high mountain pass. By 1936, the ditch extended for 17 miles through Rocky Mountain National Park. In these early cases, a transbasin diversion was much like any other ditch that diverted water from a river to wet the land where it was needed. It took manpower to shovel a conveyance, and though that was laborious, the diversions were built without further discussion, negotiation or other work beyond obtaining water and property rights. The diverting agency or ditch company would acquire land, build a diversion structure and storage, file for water rights, and put the water to beneficial use. This was all that was required, legally, while the diversions—and basin-oforigin populations—were small. There was no governmental intervention and no leadership besides that of the individual, ditch company, or financing corporation—if someone wanted water they could file for a right and get it.
1935 Delaney Resolution is adopted, requiring compensatory storage for transbasin diversions 1936 The first Denver-bound water flows through Moffat Tunnel
WATER EDUCATION COLORADO