A $9.25 million State Highway Administration project to widen and shift Route 24 away from the eroding Deer Creek stream bank through Rocks State Park will involve dynamite blasting the famous geologic structures which give the popular park its name.
Beginning next year, crews will shift Rocks Road, Maryland Route 24, 10 feet away from Deer Creek by blasting through the unique rock formations which parallel the winding road. But SHA engineers say the detonations and subsequent vibrations should have no impact on Harford County’s most recognizable natural feature – the 190-foot tall King and Queen Seat.
Engineering for the project, which is divided into seven sections that will eventually stretch from St. Clair Bridge Road to Sharon Road, is already underway and construction is scheduled from 2010 through 2012.
A rough scope of the project can be found on the SHA website.
Jialin Tian, a transportation engineer in the SHA’s Community Design Division, said erosion of the stream bank presents a safety issue for passing motorists.
“MD 24, from Stirrup Run Culvert to Deer Creek Bridge, has been identified with varying degrees of slope failure. Deer Creek continuously erodes the toe of the bank, which causes the bank to gradually steepen over time. Because of this earth movement, the traffic barrier in certain locations along MD 24 is learning away from the roadway, and tension cracking continuously appears on the road.”
“Periodic resurfacing has helped to mask the tension cracks but with reduced embankment stabilization, the road is continually in need of maintenance. The slope protection is to protect the roadway and ensure safety of all road users,” Tian wrote in an email.
Tian said the SHA has identified seven distinct sections of the road where various types of slope repairs will be needed in the future. The first efforts will cover the northern-most section, designated “Section A,” and the southern-most section, called “Section G,” which were determined to be most in need of action. The limits of Section A extend from Deer Creek Bridge to 1,200 feet south of the bridge, and the limits of section G extend from 2,000 feet south of Sharon Rd to 900 feet south of Sharon Road, Tian said.
Tian said roadway is proposed to be shifted “up to 10 feet further away from the stream than its current location in both sections” and that “rock blasting will be used in this project to remove the rocks along MD 24.”
However, Tian said the King and Queen Seat, a towering natural rock outcrop once believed to be a ceremonial gathering place for Susquehannock Indians, should not be impacted.
“The rock blasting in either section will not impact the King and Queen Seats. In general, the impact of rock blasting to the surrounding geographic features will be minimal. SHA will provide the contractor blasting provision as a guide to efficient blast design and vibration control. If there is a structure located close to the blasting area, a pre-construction survey may be performed to exam the condition of the structure,” Tian said.
Dynamite detonation was not the first choice for the Rocks Road improvement project, but, as strange as it may sound, it was deemed the least intrusive to the environment of the available options.
“Several alternatives have been studied for this project with an emphasis on protecting the surrounding landscape. Of all the alternatives studied, the only other prudent option would include the construction of a retaining wall along the stream both sections, which would impact the stream through loss of vegetation and flow diversion,” Tian said.
In addition to moving the road away from Deer Creek, the project will also widen Rocks Road, adding about six inches to each travel lane as well as a two-foot paved shoulder on each side of the road.
“Existing MD 24 has two 10.5’-11’ wide lanes with minimal shoulders. The proposed roadway in these two sections will be improved to be 26-feet wide including an 11-foot lane, and a 2-foot paved shoulder in each direction. The 2-foot paved shoulders are to provide a minimal lateral distance between the roadway and roadside obstacles, such as rocks or traffic barriers to reduce the likelihood of fixed object collisions and to provide lateral support of the pavement,” Tian said.
Anyone who lives near or regularly travels through Rocks State Park recognizes the curving creekside roadway can be quite dangerous. Tian said the improvement project should help reduce roadway collisions, especially since the posted speed limits are proposed to remain the same even as the road is widened.
“The 11-foot lanes and 2-foot shoulders are proposed to balance the speed of vehicles and while minimizing the opportunity for opposite direction crashes. This area of MD 24 currently experiences both fixed object and opposite direction crashes greater than the average statewide rate for similarly designed roadways,” Tian said.
During the construction period, SHA has proposed a full road closure since traffic cannot be safely maintained. Traffic will be detoured using MD 23 (East West Highway) and MD 165 (Federal Hill Road). Because the construction of Section A and Section G will not occur concurrently, these road closures and detours are expected to stretch over the course of the next few summers.
However, Tian said the main accesses to Rocks State Park and the accesses to the local residents’ homes “shall always be maintained.”
Additionally, SHA is continuing ongoing coordination with Maryland Department of Natural Resource regarding temporary access closures in Rocks State Park. Upon construction completion, “all accesses shall remain the same,” Tiad added.
SHA is planning an informational public meeting for late-2009 or early-2010 to inform citizens of the proposed improvements, solicit input, and answer any questions about this project.
Photo courtesy of Joshua Blankman