City Provides Answers on Sinkholes

Following the recent flash flooding at the commercial strip mall parking lot at 944 Merrimon Ave., Asheville Development Services staff visited the site of the 1010 Merrimon Ave. sinkhole.

DSD staff met with the owner, engineer (and team), and their attorney to again discuss the situation and the needed repair.

City staff again told the property owner he needed to secure the site to prevent the public from accessing it, for the safety of all. The property owner erected a chain-link fence around the site and put up “no trespassing” signs.

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DSD staff also spoke with the property manager for 946 Merrimon Ave., the Fresh Market. Staff shared information about the repair process and the property owner’s proposed temporary and permanent design solutions.

Also on Friday, July 12, the engineer submitted a permit request for temporary fix to the city — a bypass pipe, if you will. The bypass pipe will be secured with large stones as backfill and these will be topped with coarse gravel.  This is to keep the pipe in place and help support the building.

The engineer’s proposed plan for a permanent repair: Replace the pipe from the catch basin in front of Ski Country Sport to a new junction box at the property line of 1010 Merrimon Ave. and Early Girl Eatery.  However, the engineer has advised that it will take a month for the materials to be fabricated and delivered to the site.

About the backfill that has already occurred, the city has a policy that allows for emergency repairs without permits and that is the temporary emergency repair that the engineer hired by the property owner chose to do — fill in the sinkhole in this manner. The engineer chose this emergency repair to stabilize the foundation and structural integrity of the building on the site, as well as secure the property for public safety.

This temporary repair was a measure taken to save the building but had other unintended results, including washing material into nearby wetlands/bird sanctuary. The N.C. Department of Environmental Quality has issued a Notice of Violation to the property owner regarding the material that washed downstream.

Merrimon Avenue sinkhole FAQ 

Question: What happened?

Answer: A sinkhole opened up in the parking lot of an unoccupied commercial building at 1010 Merrimon Ave. on June 19.

City staff were first made aware of the sinkhole at 1010 Merrimon Ave. when the Asheville Fire Department was called to the scene on June 20.

Q: What caused the sinkhole?

A: When the property was developed, the property owner installed a pipe to allow a stream to flow through this property underground. Now, many years later, the pipe has failed.

Q: What was the city’s response?

A: The city got in touch with the property owner and advised him he would need to hire an engineer to design a repair. Development Services staff told the property owner they would work with this engineer and that he would need to submit grading permits to the city prior to making a permanent repair.  DSD staff also advised the property owner to secure the property, for safety. The engineer hired by the property owner contacted DSD staff to update staff on the efforts to secure the building and site for public safety, as is requested in emergency repair situations.

On June 27, City staff again visited the site and posted the building as unsafe for occupancy.

DSD staff notified the governing bodies at the state and federal level about this situation: the N.C. Department of Environmental Quality (regulates environmental issues) and the U.S. Army Corps of Engineers (regulates streams and rivers).

Q: Which government bodies are responsible for what in this situation?

  •         City of Asheville: Issues permits and does follow-up inspections for grading work and repairs.
  •         N.C. Department of Environmental Quality: Regulates environmental hazards. NCDEQ has issued a Notice of Violation to the property owner regarding the fill that washed into the nearby bird sanctuary/wetlands.
  •         U.S. Army Corps of Engineers: Regulates streams and rivers.

Note:  Property owner: Responsible for the repair of his property.

Q: Who is responsible for this sinkhole and its repair?

A: The City of Asheville has confirmed that discharge from the sinkhole at 1010 Merrimon Ave. into the wetland is definitely the jurisdiction of NC Department of Environmental Quality and the Army Corps of Engineers.

The city maintains the infrastructure within city-maintained right-of-way, including on city-owned property.

This sinkhole is on private property.

When the property was developed, the property owner installed a pipe to allow a stream to flow through this property underground. This pipe is on private property and therefore it is the property owner’s responsibility to maintain.

The City did not build underground infrastructure on this private property and the city does not maintain private stormwater or drainage pipes.

Q: Why did the city “allow” the sinkhole to be filled with a temporary substance that then washed down to the bird sanctuary?

A: The city did not “allow” this temporary repair. In fact, it happened on a Saturday, when the Development Services Department was not staffed and city staff found out about it after the fact.

However, the city does have a policy that allows for emergency repairs without permits and that is the temporary emergency repair that the engineer hired by the property owner chose to do — fill in the sinkhole in this manner. The engineer made a judgment call to try to save the structural integrity of the building on the site.

This temporary repair was a measure taken to save the building but had other unintended results, including washing material into nearby wetlands/bird sanctuary.

Q: Why did the engineer choose this temporary repair?

A: The engineer chose this repair to stabilize the building’s foundation and prevent further structural damage resulting from the sinkhole.

Q: What was the city’s response to this “temporary repair?”

A: City staff are maintaining close contact with NCDEQ and the Corps of Engineers on this matter.

DSD staff advised the property owner that he had 2 weeks from July 8 to submit a permit for the repair.

Once the pipe work is permitted, the next phase of permitting will be for the wetland remediation. This will be driven by NCDEQ and Army Corp of Engineers as well as the property owner.  For the wetland remediation, the City of Asheville will require a grading and flood permit. Copies of the NCDEQ- and Army Corp-approved permits will be required as well, prior to issuing a grading permit.

Q: What happened after the July 11 flashflood and rain?

A: On Friday, July 12, city staff visited the site again and met with the owner, engineer (and team) and their attorney.  City staff told the property owner he needed to secure the site to prevent the public from accessing it, for the safety of all. The property owner erected a chain-link fence around the site and put up “no trespassing” signs.

DSD staff also spoke with the property manager for 946 Merrimon Ave., the Fresh Market. Staff shared information about the repair process and proposed temporary and permanent design solutions. They were inquiring about the timeline, so we provided them the engineer’s contact information, to inquire directly to the design team.

Q: What will be the ultimate repair and how long will it take?

A: Plan for the permanent fix: Replace the pipe from the catch basin in front of Ski Country Sport to a new junction box at the property line of 1010 Merrimon Ave. and Early Girl Eatery.  However, the engineer has advised that it will take a month for the materials to be fabricated and delivered to the site.

Temporary fix in the meantime: On Friday, July 12, the engineer submitted a permit request for a temporary fix — a bypass pipe, if you will. The bypass pipe will be secured with large stones as backfill and these will be topped with coarse gravel.  This is to keep the pipe in place and help support the building.

Prepared by the City of Asheville.