How the ditch company saved Fort Collins

Moisture totals during the September floods exceeded all previous rainfall records for the month, according to the University of Colorado. The 14.5 inches of rain recorded near Boulder and Red Feather Lakes smashed the 1919 record of 4.8 inches, leading to claims of a storm of “biblical” proportions. There was also a flood of news stories as homes were washed away, people killed, bridges destroyed, dams broken and towns cut off.

Only now are some of the smaller, intriguing stories coming to light. One of these stories is about Weld & Larimer Irrigation, the ditch company that saved Fort Collins.

The storm caused an estimated $3 billion in damage. In Longmont, the flood caused $152 million in destruction. Fort Collins incurred less than $1 million. What made the difference?

“A nice mixture of prior planning, measured response and dumb luck,” Fort Collins’ floodplain manager Brian Varella said.

One piece of dumb luck was that Halligan and Seaman Reservoirs were nearly empty, able to take large amounts of water from the North Fork of the Cache la Poudre River before they too began overtopped and spilled water back into the river.

At the peak of the storm, City of Fort Collins hydrographer Beck Anderson measured 10,400 cubic feet per second at the mouth of the Poudre. That is 50 times the average annual daily flow of the Poudre of 182 cfs. But at the Linden Street bridge, a U.S. Geological Survey gauge measured just 8,900 cfs, a drop of 15 percent.

Another piece of “dumb luck” made the difference. Windsor Reservoir, located north of Windsor, was nearly empty.

Owned by WRCC, Inc. in Eaton, this reservoir gets water from two significant ditches. Every day, anyone driving the north side of Fort Collins passes over the Larimer-Weld Canal as it crosses North Shields Street near West Willox Street, or ducks under North College Avenue just south of its intersection with Colorado 1.

Early in the storm, Weld & Larimer Irrigation’s ditch manager Bill Johnson got a call from Mark Simpson, the district 3 water commissioner for the State of Colorado, asking him to open the headgates of this ditch, as well as the Poudre Valley Canal, which takes water from the mouth of the canyon, skirting north of Ted’s Place. Together, these two ditches carried 1,300 cfs from the Poudre, diverting it around Fort Collins. The gates were kept open for 6 days, pulling some 12,000 acre feet of water that did not reach Fort Collins.

According to CDOT, some 120 bridges throughout the Platte River drainage were damaged or destroyed by the erosive effect of the raging waters as the sustained erosive flood scoured rocks and dirt embankments out from under many bridges. Other had their capacity reduced as the rivers grew wider and more shallow. Debris piled up, overtopping and destroying bridges.

None of the Fort Collins bridges were seriously affected. The Shields Street bridge was pushed close to failure. If the College Avenue bridge had been overtopped, the waters would have poured down East Vine to inundate the Alta Vista-Buckingham-Andersonville neighborhoods. But it didn’t happen — thanks to the ditch company that saved Fort Collins.

In addition to Varellas’s “dumb luck,” the city can credit much of the success to the fact that it owns two-thirds of the flood plain in the city, and has strict controls on what can be built in the remainder. Along Prospect Road and near the banks of the Poudre, recent construction of the Orthopedic Center and nearby businesses was required to be elevated two feet above the 100-year flood lines. During the 2013 flood, the water reached the steps, leaving these building with a 6 six inches of freeboard. Yet, they were left high and dry — by the ditch company that saved Fort Collins?

The importance of the ditch managers was recently highlighted when the Colorado Association of Floodplain and Stormwater Managers adopted a state-wide recommendation that “ditch managers be present in the control room” during an emergency.

By opening the headgates, the ditch company suffered serious damages to the gates and canals. Logs and debris smashed repeatedly against the gates, and the gates began to spill over the top, shorting out the powerful motors that lift or lower them. In some places along the canal, concrete liners were ripped out. According to Johnson, the total damages came to some $50,000 in materials and labor wasn’t even tallied.

The ditch company must pay for the damages itself. “They took a hit for the city,” said Varella.

Did they get a letter of thanks, or even a phone call from the city? No. But Johnson was unfazed: “We’re a big company. We were able to absorb it,” he said.

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