From the Longmont Times-Call (Tony Kindelspire):
Left Hand Creek has been diverted from its main channel by a temporary earthen dam with two 48-inch pipes running through the middle of it. That’s so the workmen can rebuild the diversion dam and headgate that last September’s flood obliterated.
“We have like 13 spots that we’re working on, various levels of destruction, with this being the worst. This is the Allen’s Lake diversion,” said Plummer, vice president of maintenance and operations for the Left Hand Ditch Co. “Most everything was just buried in debris. … The Allen’s Lake diversion was just rolled up into a ball of concrete and steel.”[...]
Ditch companies control the water rights to irrigation ditches and are charged with maintaining them. The Left Hand Ditch Co. is typical of most such entities: it’s privately held and owned by shareholders — in the case of Left Hand, 460 shareholders. Sixteen percent of its shares are owned by the Left Hand Water District and goes toward drinking water, and the rest goes to agriculture.
Ditches operate using diversion dams and headgates. The dams slow the water and back it up so it can then flow through the headgate, which is opened to let water through.
In the Allen’s Lake diversion both the dam and headgate were wiped out, and in the narrow riverbed of Left Hand Canyon, the only way to replace them is to divert the river, build half the structure, then move the river again and build the other half.
“We’ll get that (side) done and then we’ll move the river back over,” Plummer said as he watched the construction crew pour concrete. “What we’re doing is racing, we’re racing the run-off.”[...]
Sean Cronin, executive director of the St. Vrain & Left Hand Water Conservancy District, attended an emergency meeting of the Highland Ditch Co. in the days following the flood.
“Not repairing this is not an option,” Cronin recalls hearing the shareholders — many of whom are farmers — saying in the meeting. “This is how we make our living.”
Cronin said there are 94 ditches and reservoirs within the St. Vrain & Left Hand district, and of those 43 suffered some amount of damage, totaling about $18 million. Some, such as the Highland, were completely destroyed.
September’s flood all but wiped out the Highland’s diversion dam and headgate, which were built in 1870. What little remained after the water subsided was not repairable.
The Highland Ditch, the biggest in the St. Vrain basin, goes all the way to Milliken, primarily serving ag land but also providing some of the city of Longmont’s drinking water.
The diversion dam and headgate were rebuilt at a cost of $750,000, according to Wade Gonzales, superintendent of the Highland Ditch Co…
The “Big Three” headgates, as far as Longmont is concerned — the Highland, the Oligarchy and the Rough & Ready/Palmerton — were all destroyed by the flood, according to Kevin Boden, environmental project specialist with the city of Longmont’s Public Works and Natural Resources Department.
The Oligarchy, it should be noted, actually held up during the initial flood but then finally gave way the following Sunday during heavy rains.
All three either have been or will be repaired by May 1, Boden said…
[Dave Nettles] said that although the Poudre, Big Thompson and Boulder Creek watersheds all sustained some damage, none of them reached the “catastrophic” levels seen in the St. Vrain and Little Thompson watersheds.
More infrastructure coverage here.