NTM Engineering assisted in performing the Lincoln Drive Resurfacing and Restoration project. Our services included evaluating the existing drainage network, designing proposed drainage improvements, evaluating stormwater management design and permitting requirements, providing temporary hydrologic and hydraulic modeling, and performing waterway permitting. NTM also designed a concrete facing with formliners for a stone masonry retaining wall that was rehabilitated as part of the project.
This section of Lincoln Drive experienced frequent roadway flooding. NTM was tasked with evaluating the existing drainage system, determining areas of need, and developing drainage improvements to reduce roadway gutter flow spread and flooding. NTM faced several unique design challenges. In multiple locations, concentrated offsite stormwater runoff flowed down the steep slope onto Lincoln Drive. There was limited space available to design improvements along the corridor. The existing roadway was cut into a steep wooded slope on one side and supported by a stone masonry retaining wall on the other side. The Lincoln Drive section was also bordered on both sides by Fairmount Park. Any proposed improvements had to consider both right-of-way and cultural resource impacts.
To address the drainage design challenges and resolve the roadway flooding issues, NTM developed innovative drainage solutions that included the use of inlet energy dissipaters consisting of a series of natural stone step pools, a settling pool, and an overflow weir. The stone step pool dissipaters were built into the existing side slope and were designed to create a cost-effective solution that safely conveys offsite runoff under the roadway, minimizes costs and project impacts, and creates a context-sensitive design that fits the aesthetic context of Fairmount Park.
As part of the reconstruction project, NTM also designed a concrete facing and formliner for a stone masonry retaining wall that parallels the roadway. Emergency structural repairs have been previously completed to stabilize the existing wall. NTM prepared plans and special provisions to construct a concrete facing with formliners to mimic the appearance of the original stone retaining wall. NTM was also responsible for temporary hydrologic and hydraulic modeling and the waterway permitting associated with the retaining wall rehabilitation work.