City of Boiling Spring Lakes
Dams Construction and Reconstruction
McGill has worked with the City of Boiling Spring Lakes since 2018, assisting with recovery from the damage caused by Hurricane Florence. We have partnered with City staff to understand the impacts that the City, its residents, and local businesses continue to endure from the loss of the lakes, some of which include recreation, aesthetic value, decreased income, increased transportation costs, increased road maintenance, and potential effects on property values.
The City of Boiling Spring Lakes lies immediately northwest of Military Ocean Terminal Sunny Point (MOTSU) and serves as a residential and recreational area for the installation. Alton Lennon Drive runs parallel to and within yards of the MOTSU railway, serving as one of only two east / west primary transportation corridors through Boiling Spring Lakes (the other being North Carolina Highway 87).
North Lake and Pine Lake dams are located to the north on tributaries of Boiling Spring Lake and serve as roadbeds for segments of East Boiling Spring Road, one of only two north / south primary transportation corridors through the City. Therefore, three of the dams in the lakes system are integral to public health and safety, providing effective disaster and emergency response, as well as daily access for most of the City’s residents.
The Challenge
Sanford Dam, impounding the 275-acre Boiling Spring Lake, suffered catastrophic failure as a result of Hurricane Florence, due to overtopping and subsequent embankment erosion. This caused cascading failures at the North Lake Dam, Pine Lake Dam, Middle Lake Dam, and Upper Lake Dam. All these dams were earthen dams, some with gated culverts or risers, and were used to maintain water levels for aesthetics and recreational use throughout the lake system. With the breaching of the dams, the North Carolina Department of Environmental Quality (NCDEQ) Dam Safety reclassified all as high-hazard dams, which subjects them to a higher tier of codes and standards. That resulted in a much more expensive undertaking than simply rebuilding the dams to pre-storm conditions.
Our Solution
McGill was honored to partner with the City of Boiling Spring Lakes shortly after the storm event to assist with dams construction and reconstruction. Led by Vice President, Michael Hanson, McGill’s water resources team and Schnabel Engineering assisted Boiling Spring Lakes in reestablishing the impounded lakes upstream of the four City-owned dams breached by Hurricane Florence. This included development of a 25-square-mile watershed-based hydrologic and hydraulic model, dam breach analysis, spillway classification, design, permitting, grant assistance, bidding, and construction phase services for the repairs to the Sanford Dam and Upper Dam, as well as North Lake Dam and Pine Lake Dam.
Design for the Sanford Dam included increasing spillway capacity via six 7-foot by 7-foot box culverts passing under Alton Lennon Road, a major arterial road at the dam, as well as several dam foundation and stability upgrades to meet current State of North Carolina standards. Additionally, McGill obtained a variety of design and environmental-related permits for this project, including 401 / 404, State Dam Safety, Federal Emergency Management Agency (FEMA) Environmental Assessment, and FEMA Conditional Letter of Map Revision (CLOMR) / Letter of Map Revision (LOMR).
A project of this caliber required multiple partners at the table to fund the $54-million reconstruction effort, including the State of North Carolina, FEMA, US Department of Defense (DOD), and Brunswick County. McGill played an integral role in assisting the City with grant compliance to secure over $17 million in FEMA disaster relief funds and has led coordination with various stakeholders to include the North Carolina Department of Transportation (NCDOT), State Historic Preservation Office (NC HPO), FEMA and Environmental and Historic Preservation (EHP), United States Army Corps of Engineers (USACE), NCDEQ, and homeowners to secure approvals and required easements.
The Results
The reconstruction of the dams to meet a new NCDEQ Dam Safety classification as high hazard will create dams that are more resilient, providing enhanced safety and functioning of the community and the challenges of the future. The increased discharge capacity of the Sanford Dam’s primary spillway will provide protection from dam overtopping, as well as increase the level of service of North Carolina Highway 87 providing uninterrupted use of these critical east / west routes during future severe storm events.
On June 17, 2023, a much-anticipated groundbreaking ceremony was held at the Sanford Dam site on Alton Lennon Road to restore the City’s lakeside view, kicking off dam reconstruction. Reconstruction efforts started in July 2023 and are expected to be complete in January 2026, bringing back the soul of Boiling Spring Lakes.
“This project has required a team effort from McGill, Schnabel, City staff, citizens, the contractor, and many other stakeholders. Through determination and collaboration over the past four years, the team has designed dam and spillway improvements, secured permits and funding, and initiated the construction needed to recover the City’s beloved lakes. While the path to completion is still years away, the accomplishments to date cannot be overstated. For a community of this size to undertake a project of this magnitude is rare. The knowledge, experience, and commitment of all involved has been the cornerstone of our success and stands as an example of how McGill strives to shape communities together.”
McGill understands the importance of this project for the City of Boiling Spring Lakes to reestablish its identity. The lakes are a center point of the City and we are proud to be partnering with Boiling Spring Lakes to restore them.
Commitment
Problem Solving
Results