Project HIghlights

  • $1.2M Construction Cost
  • Completed 2020
  • Civil Design:
    • Street Widening
    • 700-feet of RCB Storm Drain Design for over 240-Acre Tributary Area
    • Sub-Drain Design
    • Utility Relocation of Powerpoles, Streetlights & Gas Line
    • Slope Stabilization & Protection for 30-inch HP Gas Line
    • Right-of-Way Engineering – Legal Descriptions & Plats for TCE, Storm Drain Easement
  • Obtained Multiple Permits from LACDPW
  • Meeting Coordination with Property Owners and Managers

Project Description

CNC prepared the PS&E and provided surveying and construction support for the street widening and storm drain improvements on Walnut Drive South. This project entailed widening the street to a full, uniform width along a 1,400-foot stretch of road, constructed nearly 700 feet of a 6’x6’ reinforced concrete box storm drain that was designed to capture flow from over 240-acres of tributary area, new streetlight installations and SCE powerpole relocations.

  • Design and Processing: Portions of the roadway and storm drain were in unincorporated County and the City of Diamond CNC processed the PS&E for review and final approval by Los Angeles County Flood Control, Land Development and Roadway Departments. CNC prepared all supporting hydrology and hydraulic calculations.
  • Utility Relocation: CNC provided extensive coordination for the relocation of power poles, street lights, and gas line for the
  • Right of Way Engineering: CNC prepared legal descriptions and plats and conducted negotiations to obtain a temporary construction easement and permanent storm drain easement construction easement on an adjacent privately-owned temple
  • Sun-drain Design: CNC designed a sun-drain system and two groundwater monitoring wells to alleviate groundwater hydrostatic pressure at the upstream end of the