Hey, Spike! discovers Denver Water vessel mission | SummitDaily.com

Hey, Spike! discovers Denver Water vessel mission

Denver Water vessel maps Dillon Reservoir.
Miles F. Porter IV / Special to the Daily |

Quietly — without any wake — a Denver Water boat and its crew have been mapping the underwater contours of Dillon Reservoir.

The crew of captains Angleo Martinez and Jerry Kahl have been conducting the hydrographic survey for two summers, working four-day, 10-hour shifts aboard an outboard engine-powered aluminum-hulled pilothouse vessel.

Smoothly plying the chilly waters of the Denver Water-owned lake covering 3,233 surface acres, the bathymetric survey craft goes systematically about its business, much like a lawn mower, covering and recording the always-changing contours of the popular water source that is seeing more and more recreation use.

While there are increasing usage numbers for the lake, stemming from its two marinas and campgrounds, there is the ever-growing deposits of silt coming from the Tenmile, Blue and Snake river flows.

Denver Water senior spokesperson Travis Thompson explains the whys for the mapping this way:

“This survey enables Denver Water to learn more about our actual reservoir capacity. Denver Water has mapped reservoirs for years, but surveyors had only a rudimentary single-beam sonar on a rickety aluminum fishing boat. We are now utilizing a dedicated hydrographic vessel, the standard used by the Army Corps of Engineers and hydrographic surveyors for large rivers, harbors and anchorages, to collect much more precise data. Once complete, Denver Water planners will use the information to determine where sediment is piling up, reducing reservoir capacity. Additionally, dam safety engineers can use the data to understand what’s behind the dams.”

In-filling sediment cuts down the reservoir’s storage capacity, and on the Frisco Bay Marina side, it affects the power and sailboat traffic flows.

“We are just collecting data right now. Once this phase of the project is complete, Denver Water’s survey team will process and edit the information collected. At that point, we’ll produce a more precise visual of the reservoir bottom,” Thompson explains.

The build-up of silt is a slow process — usually, making the results of the survey information long-lasting.

“The survey will not need to be done at Dillon Reservoir again for decades,” Thompson said. “However, if something were to occur causing an increase of sediment to the reservoir, it could prompt another survey to help us determine any capacity loss.”

The mapping process will prove beneficial to the town of Frisco’s marina operations since it has in-hand a federal permit to dredge out the basin when a variety of factors align favorably, such as water levels and flows and timing.

Denver Water continues its cooperative spirit since welcoming the founding of the Frisco marina by the Frisco Bay Yacht Club in 1988.

And it has backed that up with funding.

“Through the Colorado River Cooperative Agreement, Denver Water has provided money to the town of Frisco to offset costs of projects like the redevelopment and dredging of the Frisco marina,” Thompson said.

Some interesting numbers for the high altitude body of water are these:

• Construction on the earthen dam started in 1961 and the lake first began filling in 1963.

• Deepest point is 207 feet.

• Distance to drive/bike around it is 17 miles.

• Actual shoreline covers about 26 miles.

• At full-pool, the reservoir has an elevation of 9,017 feet.

• Dillon Reservoir has become home to nesting bald and osprey eagles.

Miles F. Porter IV, nicknamed “Spike,” a Coloradan since 1949, is an Army veteran, former hardrock miner, graduate of Adams State College, and a local since 1982. An award-winning investigative reporter, he and wife Mary E. Staby owned newspapers here for 20 years. Email your social info to milesfporteriv@aol.com


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