Gross Reservoir Expansion Project

Denver Water will be conducting a subsurface investigation program to support design of the Gross Reservoir Expansion project from June 2018 through October 2018. This work will take place in various locations on the south side of Gross Reservoir. These locations were chosen because they represent areas where knowledge of the subsurface conditions can inform work currently proposed on project features. Land disturbance from the investigation activities will be minimal and not cause major disruptions to traffic activities around Gross Reservoir. The subsurface investigation program will include three types of activities which are described below.

  • Geophysical Survey is non-destructive testing of subsurface strata by introducing energy into the ground and receiving the energy reflections with geophones placed along the surface. The energy source is often pounding a sledge hammer onto a metal plate. The geophones receive information that is collected and then processed to produce estimate characteristics of the subsurface materials. No chemicals will be used during the data collection process.
  • Test borings will be gathered by a drill rig and vary in width and depth depending on the location and conditions. Extracted rock will be placed in boxes and transported for additional analysis. The drill holes will be grouted upon completion according to the Colorado Division of Water Resources Water Well Specifications.
  • Test pits will be dug using backhoe equipment and range in depth from 5 to 15 feet. The final dimensions will vary based on materials encountered. Upon completion of the excavation and documentation process, removed soil will be returned to the test pit and returned to approximate original grade.

Latest News / Blog

A statement from the CEO/Manager

Below is a statement from Denver Water CEO/Manager, Jim Lochhead, regarding the Boulder County land use process: "The location of the current and expanded Gross Dam was defined as a 'Flood Regulatory Area' before the enactment of 1041 permitting in 1974, which makes...

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