FRISCO - To the drivers speeding by, it may look like a boring job.
The team of 20 Dillon Dam Road security guards, most of them off-duty law enforcement or military veterans, work eight- to 12-hour shifts watching 5,000-7,000 cars a day pass by from the driver's seat of pickup trucks parked at either end of the road.
But, though they look relaxed as they wave and smile at familiar cars, the guards are on high alert.
"You really don't have time to be bored," head of security Harry Sprague said. "You've got to be well focused."
The guards are charged not only with keeping larger vehicles - including RVs and 18-wheelers - off the narrow road, but with protecting the road and the structure itself by surveying every car that crosses it.
On the Frisco side, guards have less than 8 seconds to assess and respond when a vehicle rounds the corner toward the dam.
"The guards' primary responsibility is security of the dam and its related facilities," Denver Water spokeswoman Stacy Chesney said. "A secure dam means increased safety of the residents of Summit County and the Denver-metro area."
The well being of the Dillon Dam is key to the security of both.
A failure of the Dam could flood Silverthorne with some 84 billion gallons of water and empty Denver Water's largest water storage facility, depriving the metro area of a critical water source.
Constructed in the 1960s, before terrorism was a factor considered in the course of infrastructure projects, the Dillon Dam was unprotected for most of its history. But the world changed after Sept. 11, 2001.
"It was kind of one of those situations where, all of a sudden, you're aware that something could happen to it," Denver Water director of operations told the Summit Daily in a previous interview. "So you start to think about that facility completely differently."
In 2008, citing an unspecified security threat, Denver Water closed the road to traffic at night and staffed a team of former military personnel and police officers to protect it during the day.
In 2011, the Dillon Dam Road was closed completely for several weeks while security was revamped with new guard shacks on either end of the structure, improved lighting and roundabouts. With the completion of the project in October, the road was reopened 24 hours a day with guards stationed on either end around the clock.
"The mission," said Sprague, a former Marine, "is to protect Denver Water property and personnel."
But it is also to keep restricted vehicles - large commercial trucks, 18-wheelers and recreation vehicles - off the narrow road, to monitor conditions during winter storms and, often, just to be friendly and helpful to motorists.
"You feel like a tour guide sometimes," says Sprague, after genially discussing ice-fishing spots with a man who stopped to ask if the activity was allowed around the dam.
But every once in a while, the security guards on the dam are called on to be more than Good Samaritans.
In 2010, they stopped and saved the life of a man who smashed through barricades on the Dam Road in a stolen car.
The man ran through plastic barricades and drove onto the Dam Road after midnight. As Sprague and his partner, Jeremy DuFour, attempted to close in on the rampaging car, the driver plowed into a guardrail and, in an attempt to escape, jumped the railing on the opposite side of the reservoir and rolled down the steep embankment.
Using searchlights, DuFour located the man and called law enforcement.
By the time officers got to him, the culprit was incoherent and losing consciousness. DuFour and Dillon police officer Joe Staufer were able to revive and stabilize the man, who was transported to the hospital.
There still has never been a fatality on the Dillon Dam Road.