Project Overview

As part of their commitment to provide potable water of unquestionable quality to the residents of Southeast Michigan, GLWA undertook water transmission piping upgrade projects to rehabilitate/ replace 14.5 miles of aging water infrastructure in the City of Detroit. As part of a multi-disciplined design-build team, NTH was tasked to complete geotechnical investigation, subsurface utility investigation, environmental contamination evaluation, and wetland, threatened and endangered species, and historical landmark evaluations to ensure a successful project outcome.

Project Scope

NTH was retained by Structural Technologies to provide design support services to their multi-disciplined design-build team for two water transmission piping upgrade projects for over 14.5 miles in the City of Detroit of pipeline including:

  • Garland, Hurlburt, and Bewick Water Transmission Main: 6.9 Miles between Jefferson Ave. and I-94
  • 7 Mile/Nevada Transmission Main: 7.5 Miles along 7-mile and Nevada between Livernois Ave. and Van Dyke

NTH’s services included the following for each transmission piping upgrade project:

  • Geotechnical Investigation and Report – performed a geotechnical investigation along the transmission main alignments and prepared a geotechnical report that presents the results of our subsurface exploration, geotechnical recommendations, construction considerations, and results of laboratory testing needed to complete the design. The geotechnical report will identify geotechnical conditions and parameters to be used by the design/build team in designing the improvements.
  • Subsurface Utility Investigation – performed quality level B and quality level A subsurface utility investigation at select locations along the transmission main alignments to provide additional design information for the design team including confirmed elevation of the existing transmission mains and utility crossing/ conflicts to prepare construction documentation.
  • Environmental Corridor Study – prepared an inventory and environmental risk assessment of Areas of Concern (AOCs) along the transmission main alignments in conformance with ASTM E1527-13 to determine potential contamination implications for future construction. Evaluated specific AOCs with a subsurface environmental investigation (SEI) including completing environmental borings and laboratory testing for soil and water analysis to evaluate for and quantify environmental constituents of concern for future construction documentation purposes.
  • Hazardous Material Survey of Pipeline Appurtenant Structures/Vaults – surveyed the existing structures that may be modified or demolished for hazardous materials (HAZMAT), including but not limited to lead-based paint, asbestos containing materials, mercury-containing materials and equipment, polychlorinated biphenyl (PCB) containing materials and equipment, Resource Conservation and Recovery Act (RCRA) Universal Hazardous Wastes, and petroleum-stained surfaces and incorporate the abatement and removal of said materials into the design of the project.
  • Wetlands, Threatened and Endangered Species, and Historical Landmark Evaluations – performed the requisite surveys to identify and inventory sites along the transmission main alignments that presented historical preservation, wetlands, threatened and/or endangered species impacts for the project.
  • Permitting Assistance – in order to facilitate our work within public rights-of-way (ROW), NTH provided extensive permitting experience for access and work within the transmission main alignments including City of Detroit, Wayne County, MDOT, and GLWA.
Client Benefit

NTH helped provide accurate existing conditions information related to geotechnical, subsurface utility, and environmental contamination and associated impacts for the project. By providing compilation of data for existing conditions, the design team was able to accurately plan and mitigate future concerns related to geotechnical, environmental, and subsurface utility elements of the project.