AGENDA# 6a
MEMORANDUM
TO: Mayor and Town Council
FROM: W. Calvin Horton, Town Manager
SUBJECT: July 2000 Storm Incident Report
DATE: August 28, 2000
The following report discusses issues and outcomes regarding the heavy rainfall and subsequent flooding associated with a storm during the night of July 23-24, 2000.
During the night of July 23-24, 2000, the Chapel Hill area received 5-8 inches of rain over a 6-hour period. The greatest amount of this rainfall was in the watersheds of Booker and Bolin Creeks. Unofficial reports received from citizens indicate that an excess of 8 inches fell in some areas of the Booker Creek watershed.
Precipitation records at OWASA dating back to 1948 indicate that this amount of rainfall over a 24-48 hour period has occurred due to hurricanes, but not over the extremely short duration of 6 hours. This extraordinary rainfall event resulted in significant runoff with associated flooding and damage in several areas of the Town.
During and following the July 23-24 storm, Chapel Hill experienced problems ranging from localized power outages and short-term street and yard inundation to significant flooding of residences and businesses with resultant property damages. We are not aware of any severe injuries or loss of life directly associated with the storm.
Most storm and flooding related incidents occurred in “problem areas” where we have previously experienced difficulties; however, the severity and extent of flooding and erosion in many cases exceeded our recent experiences with major storm events. We attribute this primarily to the characteristics of this storm, which included very heavy rainfall over a relatively short period of time within the boundaries of two of the Town’s contributing drainage areas, Booker and Bolin Creek watersheds.
The following information summarizes the major storm-related problems which occurred, and the associated responses:
1. Flooding at Eastgate Shopping Center
Eastgate sustained an extraordinary amount of flood damages. All shopping center buildings received some degree of flooding, several feet deep in some cases. Many businesses remain closed due to the needed repairs.
Town officials met with owners’ representatives (Federal Realty) and tenants, and began to provide technical assistance to the extent possible. Eastgate Shopping Center is private property, and the Town’s direct role was limited to immediate follow-up activities as follows:
1. Encouraging the shopping center owner to inspect and maintain the culvert passing beneath the center. This activity is currently underway.
2. Encouraging the shopping center owner to perform a flood mitigation engineering study to provide for possible long-term solutions to the flood problem. This activity is currently underway.
3. Providing the tenants with structural floodproofing literature (such as installing door gaskets or barriers) and with information concerning flood insurance applications.
4. Requesting that a thorough cleanup take place in the areas immediately downstream, where significant amounts of trash are deposited. This activity was completed soon afterwards by Federal Realty.
5. Coordination of an Emergency Response Plan with assistance from the police and fire departments.
6. Waiving all permit fees associated with reconstruction and expediting all applications. To date, five permit fees have been waived.
The Small Business Administration set up a temporary office in Town to assist business owners in Eastgate, and elsewhere in Town, to obtain low interest loans for repair of storm-related damages to their businesses.
2. Flooding at Camelot Apartments, Brookstone Condominiums, and Booker Creek Apartments
Sixty units in this complex received flooding to varying degrees, with resultant property damage. This flooding occurred on private property and the Town is not playing a direct role in repairs.
Repair work is in progress and has been completed in many of the damaged dwelling units. Twenty-five units have been reoccupied to date. The Town Building Inspections Department is expediting issuance of permits and inspections relating to the repair work, as well as waiving permit fees.
Town staff have met with a member of U.S. Representative Price’s staff to identify possible sources of federal funding for a buyout program targeting occupied properties experiencing chronic flood damages. Preliminary discussions with the NC Division of Emergency Management have taken place and will continue.
We also discussed possible funding sources for a large-scale flood mitigation study involving Booker and Bolin Creeks. One possible source is the US Army Corps of Engineers Section 205 Program. Consideration for participation requires that a formal request be sent to the Wilmington District office. The cost would be 100% federally funded, up to $100k for such a study. We will continue to pursue this opportunity and will keep you informed.
3. Flood damages to Town Facilities and infrastructure
The Town sustained some damages to facilities in Umstead Park (estimated $17,000) and along the Booker Creek and Bolin Creek greenway trails (estimated $13,000). Most damage resulted from erosion and scouring caused by fast-moving water. This damage included erosion of embankment areas along the greenways and loss of the sand base in the Umstead play area as well as the pedestrian bridge.
These damages are in the process of being repaired by both Town and contract forces.
We also experienced erosion and movement of streambed and bank materials around most of our bridge structures. None of the structures themselves were seriously damaged. Town forces are presently repairing erosion damage and replacing rock lined reinforcement areas around the bridge supports. Contract labor may be utilized for these projects as well.
Minor flooding to ten units in Airport Gardens Apartments occurred. Town forces assisted with the cleanup. No flooding was reported in any other Town housing facilities.
Engineering staff conducted bridge inspections and other drainage assessments and found one street bridge in need of immediate repair, North Lake Shore Drive at Booker Creek. Repairs were conducted for the bridge with safety concerns and the remaining repairs, considered minor, will be performed by Public Works or contracted out. A project list has been generated of all remaining repair needs with a total estimated cost of $41,550. Some of these potential projects fall under the Drainage Assistance Program, in which the property owner provides the cost of materials.
4. Piney Mountain Road Washout
The most significant infrastructure damage occurred on Piney Mountain Road east of NC 86 where a portion of the roadway washed out around a culvert. This required the closure of Piney Mountain Road until repairs are completed. Please see the following separate memorandum on this repair project.
5. Flood Study Update
The US Army Corps of Engineers has transferred the remaining study workload over to a private contractor. Due to the complexities of performing an adequate study, the contractor will provide the Corps with a proposal to perform the remaining work. The Town and the other local study participants will then review the proposal prior to making final decisions as to the scope of the final work to be performed.
This project is vital in that it will ultimately produce new regulatory flood maps for the Town’s continued participation in the FEMA’s National Flood Insurance Program (NFIP). To ensure and enhance our participation in the NFIP, we think that the Town should partner with FEMA under the Cooperating Technical Communities Program (CTC). With such a partnership, close coordination and involvement in the flood hazard mapping process will result in more efficient and effective floodplain management in Chapel Hill. The Town of Carrboro has indicated their interest in learning more about CTC as well. Talks with Carrboro staff are occurring presently and we will let you know the results.
6. Stormwater Utility Committee Update
The Stormwater Utility Committee kick-off meeting was successfully held August 21st and the current membership turnout was almost 100%. Several additional memberships have been proposed. James T. Mergner of UNC Facilities Services was elected as Chair and Phil Berke of UNC-CH was elected as Co-Chair.
The committee discussed broad issues concerning the need to educate each other and the general public about stormwater issues and to determine what the perceived and real needs are within this context. Of immediate concern was that such a utility would not create a fair and equitable program, whereby specific needs may not be addressed such as retaining existing basic controls within each jurisdiction. Thus, the need for close jurisdictional cooperation was stressed during the recommendation process.
It was decided that further information was required relating to existing and future programs which a stormwater utility may create or enhance. One such program is utilization of GIS technology to map existing storm sewer systems and serve as a base map indicating flood hazard areas. Another is planning for compliance with the EPA National Pollution Discharge Elimination System (NPDES) Phase 2 water quality regulations, requiring general permits by March, 2003. Other issues discussed included watershed boundaries and upcoming public education meetings, sponsored by the NC Department of Environment and Natural Resources on the NPDES Phase 2 requirements. Committee members were asked to try to attend at least one such meeting.
The committee will hold it’s next meeting on September 18th, 5:30 – 7:00 pm, at the Chapel Hill Town Hall.
7. The Oaks I & II Subdivision Flood Meeting
On August 17th, Town staff, elected officials and representatives from OWASA and the US Army Corps of Engineers attended a meeting hosted by the Oaks Homeowners Association. The residents had concerns and questions related to the recent flooding as well as past flooding within the Oaks Subdivision. The questions related to what occurred on July 23-24 and how the flooding could be stopped or reduced during future storm events. They asked that short-term and long-term solutions be considered.
Attached is a summary of what issues were discussed entitled “The Oaks Flood Meeting Summary”.
Both the public and private sectors of our community incurred significant damages from the storm of July 23-24, 2000.
Damage repairs are underway or have been completed in most of the affected areas.
The Town is investigating possible funding sources for both a buyout program and a flood mitigation study. If such funding sources can be identified, we will return to the Council for authorization to pursue them. A partnership entitled Cooperating Technical Communities, between the Town (and possibly Carrboro) and FEMA is recommended for a more efficient and effective coordination of mapping flood hazard areas. Carrboro is reviewing this partnership option with Chapel Hill. If Carrboro wishes to be a joint partner with Chapel Hill, a letter will be sent to FEMA indicating so. In any case, Chapel Hill will send a letter requesting that the partnership process proceed.
Piney Mountain Road repairs are of immediate importance regarding public infrastructure and the replacement design is currently underway. Please see the separate report on this issue.
1. The Oaks Flood Meeting Summary (p. 6)