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Follow the Process: Denver Water's Plan to Expand


While the expansion of the Gross Reservoir will have a great impact on Boulder County over the next seven years or longer, the extra drinking water supply created from the expansion will exclusively serve Denver Water customers at the expense of Boulder and surrounding areas.


The project was intended to address an expected water shortfall that would have hit in 2016. However, due to conservation efforts, that shortfall never happened. Sustainable water management practices are required in this era of drying climate. Expanding Gross Dam is using 20th century technology to solve a 21st century challenge.


Rather than spending $380 to $450 million (and maybe more) on a dam expansion project that threatens our local environment, we should concentrate our efforts on continuing water conservation efforts in the Denver area and look for ongoing, sustainable solutions to support a growing population in a world affected by climate change. Climate scientists tell us that by the middle of this century there will likely not be enough water to fill even the existing reservoir, let alone a larger one. This ill advised project, should it proceed, may well result in Denver Water "building" a big, dry hole.  


The timeline below features downloadable resources to follow the process from its origin to where we are today:

Denver Water submits 1041 Application

SEP 2020

Denver Water requests dismissal in Gross Reservoir appeal - asks Boulder County to review expansion project

JUL 2020

Denver Water Submits 1041 Application and Boulder County Land Use Department will not accept until litigation ends.

JUL 2019

Save the Colorado & The Environmental Group Granted Motion to Intervene on behalf of Boulder County

JUNE 2019

Denver Water Sues Boulder County

APR 2019

Boulder County Commissioners unanimously vote to force Denver Water through local 1041 process.

MAR 2019

Save the Colorado and TEG Files Suit against Army Corps of Engineers


Federal Energy Regulation Commission (FERC) letter regarding drilling program plan
FERC responds to Boulder County's letter regarding the proposed amended drilling plan by Denver Water.


Supplemental environmental assessment by Save the Colorado and The Environmental Group
These organizations filed public comments dependent on the work of several qualified experts who have prepared technical reports in their respective fields.


Comments on vegetation removal and associated activities as a result of Gross Dam expansion
Rocky Smith's assessment of the impacts of forestry issues and vegetation removal in the FERC Supplemental Environmental Assessment.


Supplemental environmental analysis regarding considerations for special aquatic resources
Grand Environmental Services focuses on Denver Water's proposals regarding special aquatic resources including riffle‐pool complexes and jurisdictional wetlands.


REPORT: Actual versus projected water demand for Denver Water customers
Report prepared by Lisa Buchanan of LRB Hydrology & Analytics analyzing Denver Water's projected demand versus actual demand over two decades.

APR 2018

Boulder County's comments to FERC on the Supplemental Environmental Assessment
Boulder County is an intervenor in this action and offers these comments related to the Gross Reservoir Hydroelectric Project.


The Environmental Group's letter to Boulder County Commissioners about Gross Dam Expansion
The Environmental Group calls on the Boulder County Commission to oppose the Gross Dam expansion project due to increasing concerns.


The Environmental Group's comments to FERC regarding Gross Dam expansion
The Environmental Group responds to Denver Water's Application Amendment to expand their hydroelectric project at Gross Reservoir.


US Army Corps of Engineers release draft Environmental Impact Statement
This Draft Environmental Impact Statement (EIS) evaluates the effects of a water supply project called the Moffat Collection System Project (Moffat Project).


Denver Water's final borrow haul study and alternatives analysis
HDR Engineering, Inc. analyses methods of transporting and hauling materials to complete the Gross Reservoir expansion project.


Boulder County Commission's letter to FERC, Denver Water, and the Army Corps of Engineers
Boulder County Comments on the Moffat Collection System Draft EIS and Draft FERC
License Amendment Application


Denver Water's draft FERC hydropower license amendment application
Denver Water seeks to amend its Federal Energy Regulatory Commission (FERC) hydroelectric license for Gross Reservoir (FERC Project No. 2035).

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