ANCHORAGE -

The Richardson Highway remains closed after two avalanches created a snow dam that Department of Transportation officials say is holding back large amounts of water.

The depth of the water remains unknown, but officials say snow removal will not proceed on either side of the dam out of fear of water surges that could endanger the lives of DOT workers. There is currently no timeline for when that work will begin.

By Friday, Jan. 24, the highway was closed from mile 12 to mile 65 through Keystone Canyon after several slides blocked the road, including two that deposited an estimated 30 to 40 feet of snow across the roadway and up to 100 feet in the river.

On Monday DOT officials said a maintenance engineer arrived in Valdez to assess the situation. Officials say the water behind the avalanche had receded about 18 inches by 6 p.m. Sunday, flowing beneath the snow pack as well as through an old railroad tunnel.

Currently crews are doing other work in the area, waiting until the water recedes to begin clearing the highway. Once crews begin work, DOT officials say clearing efforts will be a non-stop operation.

The highway is expected to remain closed until at least next Sunday, Feb. 2. But officials say it could  very possibly be longer.

On Monday the Valdez City Manager, Police Chief, and Fire Chief conducted aerial reconnaissance in helicopters to assess the situation. A state hydrologist said a catastrophic failure of the snow dam is considered very unlikely, but local flooding could be a possibility.

In an update form the Deputy City Clerk, Holly Wolgamott, Safeway had committed six trailers worth of supplies and food, unloading and stocking produce and dairy products. If the road remains closed, Wolgamott said Safeway would continue to barge food into Valdez as needed.

Schools remain open and continue operating on a normal schedule. City officials say they do not foresee any issues at this point.

The city says it’s working to increase ferry traffic along the Marine Highway System while the road is closed. The airport and port facilities remain available, officials said.

The mayor of has called for a special City Council meeting , to be held at 6 p.m. Monday at the City Council chambers. The meeting is open to the public.

While state crews are gearing up for an around-the-clock effort to clear avalanche-blocked Richardson Highway, two people are accused of slowing avalanche mitigation efforts by getting in the way of explosives.

GETTING IN THE WAY

Department of Transportation and Public Facilities crews were working Saturday to clear an area near the highway from mile 12 to mile 39.

According to a Monday Alaska State Troopers dispatch, that effort was slowed when two Valdez men allegedly walked across a stretch of the avalanche-blocked Richardson Highway, delaying avalanche mitigation efforts using explosives.

Troopers in Valdez were told by DOT officials Saturday afternoon that people -- later identified as 20-year-old Donney Carlson and 22-year-old Kristina Clark -- had walked across an avalanche at Mile 39 and said they were headed to Valdez.

“They were informed from DOT, and the troopers, the road was impassable and they were to turn around,” troopers wrote. “After refusing to listen to the direction from DOT and troopers, both parties were transported to Valdez via helicopter and subsequently arrested.”

DOT was forced to shut down its work during the incident, which the Associated Press reports involved crews dropping aerial explosives on avalanche chutes to avert further slides. That task was not completed until Sunday.

In a Sunday criminal complaint, Trooper Anthony Beck wrote that AST first learned of the case from at about 3 p.m. Sunday. DOTPF crews said they had warned Carlson and Clark of both the highway's impassability and the mitigation work being done, but they said they would continue to Valdez. When Beck was personally notified at 3:20 p.m., he gave officials a message to relay.

"I advised them to tell (Carlson and Clark) they are working under the authority of the Alaska State Troopers, and they were to turn around and head back to Glennallen," Beck wrote. "They were also advised a second time that the road was impassable."

When the two again refused to turn around, DOT stopped work and offered them a helicopter ride to Valdez, noting that troopers would be waiting for them. They agreed and were flown out.

In addition to delaying workers' schedule for cleanup work, Beck said the walkers placed them in peril.

"These actions further created a hazardous situation to DOT personnel because they were forced to drive through unsafe areas of the Richardson Highway to deal with Carlson and Clark," Beck wrote.

Carlson and Clark were held at the Valdez Jail and each charged with disorderly conduct -- as well as obstructing a highway.

KTUU's Mallory Peebles and Matthew Smith contributed to this report