The East Branch Dam Safety Modification Project is moving along. In June, design plans were completed as was approval to begin construction on the $280 million, multi-year project anticipated to have a 2017 finish date.
The proposed plan of creating a full-length cutoff wall at the lake is in response to a 1957 erosion incident which could have led to the dam failing. At that time, a cavity allowing muddy seepage was grouted to prevent dam failure. Although dam conditions were studied and monitored from that time until the present, the repairs were never authorized, and in 2008 it was concluded that the potential for seepage-related failure still exists. Pre-construction activities on the cutoff wall project are anticipated to begin in September and last until December 2012, dependent on funding.
According to Mike Rattay, project manager from the U.S. Army Corps of Engineers, the vast project entails improving access roads to the site and preparing a local on-site office and material lay-down areas for contractors and the government. All of these contracts were approved in June.
Initiation of construction is dependent on receiving approval from the Assistant Secretary of the Army for Civil Works.
"We are looking at ways to refine this plan," Rattay said. "We have brought on team members of the Corps from the national level. They bring a lot to the table on refining it. We are feeling good about the project."
The cutoff wall is expected to be 300 feet deep; however, since personnel are unsure if conventional equipment can go that deep, they decided based on the experience of the team members and the advent of better construction industrial capabilities to make the wall 250 feet deep and 39 inches wide instead of 55 inches.
"We will see a reduction in cost and this will help in positioning ourselves with construction funds," Rattay said.
He added that this year, the project is funded to full capability.
"Every year is a fiscal challenge," Rattay noted.
In 2012, the project is estimated to receive the same amount of funding as it did this year. An allotment for dam safety projects has been set aside for all projects nationwide. In 2013, personnel plan to submit an informational package in hopes of having the wall fully funded.
Planned site development includes work to 7,000 feet of nearby access roads, beginning at the state route and ending at the control tower, to allow large trucks easier access to the construction site. Currently, the two-lane road includes eight-foot lanes and a small shoulder on each side. Renovations being planned are for two nine-foot lanes with a four-foot paved shoulder.
This portion of the project is estimated to take 400 days to complete, with the bids being awarded in September and completion expected in November 2012. One lane of the road will be maintained throughout this portion of the project.
"We are going to try to minimize inconveniences as much as possible to property owners for both personal and emergency uses," Rattay said. "The roads are being built to Jones Township standards, which exceed PennDOT standards."
Consideration is also being given to construct a concrete batch plant on-site, as there is a concern about possible damage being done to local roads in transporting the material from out of the area. The concrete will be used inside the cutoff wall.
Problems at the dam stem from its original construction, as it was made with a highly erodible soil cutoff trench into rock with untreated joints. This made for a high potential of erosion of soil under water pressure from the reservoir and led to the 1957 erosion incident.