Wednesday, March 06, 2013
ADOT estimates $35 million to repair landslide damage to US 89
The Arizona Department of Transportation has been granted $2 million in immediate federal aid that can be used to continue investigating the cause of a landslide on a stretch of US 89 last month south of Page.
Following Governor Jan Brewer’s Declaration of Emergency last week, ADOT asked the Federal Highway Administration for the quick release of emergency relief funds and submitted an initial estimate to complete repairs of $35 million. This estimate may change as further information about the landslide is gathered by engineers.
The quick release funds will be used to assess the damage and the stability of the mountain slope, and conduct emergency operations.
The Federal Highway Administration’s emergency relief program reimburses state and local agencies for the repair or reconstruction of highways, roads and bridges that are damaged in natural disasters and catastrophic failures.
“Our budget for emergencies is very limited, and local governments have even greater financial constraints with limited cash available to fund emergencies,” said Jennifer Toth, ADOT deputy director for transportation. “This initial allocation serves as a down payment on the overall emergency relief needs for US 89. It will offset the cost for the geotechnical investigation of the landslide area to determine short- and long-term options.”
ADOT is currently conducting a geological investigation to determine the stability of the mountain slope in the Echo Cliffs. The agency is also performing damage assessments in the area and a more accurate estimate will be available in the future.
US 89 is currently closed between the US 89A junction near Bitter Springs to the State Route 98 junction near Page (mileposts 523-546). The highway has approximately 500 feet of damage, including 150 feet of pavement that settled four to six feet, due to a landslide and failure of the slope during the early morning hours on Feb. 20.
While US 89 remains closed indefinitely, the primary detour route is to take US 160 to SR 98 toward Page. Drivers also have the option to take US 89A north to Marble Canyon toward Fredonia to reconnect to US 89 in Kanab, Utah.
ADOT’s plan to fix landslide on Highway 89 near Page
by Jonathan DuHamel on Jul. 15, 2013, under Geology
On February 23, 2013, a large landslide occurred on Highway 89 about 25 miles south of Page, Arizona. The Arizona Department of Transportation (ADOT) closed the highway and has been studying how to fix it. Currently, to get from Bitter Springs to Page requires a 45-mile detour (see map here). For more background, see my post here which links to some updates and a video.
The Highway was originally built over a portion of ancient landslide as shown in the photo below (annotated by Wayne Ranney), rocks slid from the red line to the yellow line:
The next photo, ADOT Figure 1 from a 463-page geotechnical report shows the condition of the highway just after the February slide. Displacements in the pavement are up to six feet vertically. The active landslide is approximately 135 feet below the roadway and measures approximately 1,200 long at the base of the slope. It took out about 150 feet of road.
ADOT figure 6 shows an annotated cross-section. The February slide is the small red arc on the left side of the photo.
The fix recommended by ADOT (see press release) is to “move the road 60 feet [east], and take the rock from the cut and put it at the base of the hill to form a rock buttress to lock in the recent slide.” “The right-of-way and environmental
process will be our biggest challenge, but we will streamline that as much as possible so we can benefit the traveling public and especially the Bitter Springs and Marble Canyon communities.”
process will be our biggest challenge, but we will streamline that as much as possible so we can benefit the traveling public and especially the Bitter Springs and Marble Canyon communities.”
The repairs will cost about $40 million and take more than two years to complete. Meanwhile, ADOT is paving Navajo Route 20 which parallels Highway 89 to the east to establish a shorter detour route for motorists until repairs are complete on US 89. Money for this comes from a $35 million federal grant. “Construction started in late May on N20 and is scheduled to be completed in August.”
ADOT has a dedicated webpage for this project at http://www.azdot.gov/us89/ to keep us informed.
Highway 89 is the main route from Flagstaff to Lake Powell and Utah. An editorial in Flagstaff’s Arizona Daily Sun (reprinted in the Arizona Daily Star) asks why bother to fix Highway 89 when the alternate route, Navajo 20 is being improved. Why indeed. Why spend $40 million on a fix of Highway 89 that will take it over a geologically unstable landslide, when a reasonable, though less scenic, alternative is available? See map below:
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