Moapa Valley Collection System

Project Type:
  • Wastewater Facilities
  • Bidability/Constructability Review
Construction Budget: $44,600,000
Client: Clark County Water Reclamation District
Service Performed:
  • Wastewater Flow Analysis
  • Gravity Sewer System Design
  • Lift Station Design
  • Force Main System Design
  • Permitting
  • Environmental Support
  • Biological Assessment
  • Jurisdictional Determination Wetland
  • Delineation
  • Utility Coordination
  • Survey
  • Right-of-Way
  • Cost Estimates
  • Specifications
  • Bidability/Constructability Reviews
  • Value Engineering

GCW Moapa Valley Collection System

GCW completed a predesign report that evaluated approximately 11,000 acres with an estimated peak sewer flow of 29 MGD. The predesign report presented the concept for the 14.5-mile trunk sewer system in the community, a 29 MGD peak sewage lift station, and a 1.5-mile force main system with an estimated cost exceeding $60 million. From the predesign, the CCWRD scaled back the scope to include approximately 43,300 linear feet of gravity sewer lines ranging in size from 8-inch to 36-inch, and to include a service connection to each property owner adjacent to the alignment.  Additionally, GCW was tasked with designing a 3-stage lift station to accommodate up to 3.8 mgd pumping capacity with a 9,000 CFM 3-stage odor control system and two 16-inch force mains each approximately 1.6 miles long. Finally, GCW designed a nearly 2-mile long 16-inch water line to provide water from the existing distribution system to the Water Resource Center.  The force main and water line include two tunneled sections, one under the Muddy River and the other under a small hill, with nearly 860 linear feet of 30-inch casing and 570 linear feet of 60-inch casing.

Project included preparation and approval of an Environmental Assessment, Jurisdictional Determination and Wetland Delineation in support of the construction of the Lower Moapa Valley Collection System which included work within the Overton Wildlife Management Area.  An amended right-of-way was required for the project from the National Park Service, which served as the federal nexus for the NEPA action. Project elements included preparation of Purpose and Need Statement, Project Alternatives and analysis of affected environment.  GCW coordinated work of environmental and cultural resources specialists, assisted with document preparation, managed subconsultants, coordinated preparation of Biological Assessment and coordinated the preparation of the Jurisdictional Determination.  GCW coordinated the acquisition of the right-of-way from National Park Service.  The Jurisdictional Determination will be utilized as support for future USACE 404 Permits in the project area.