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• Board Meeting Date: 9/16/2008
• Description: IWMD Section - Presentation on Northern Integrated Supply Project ‎(NISP)‎
• Board Meetings - Doc Type: Memo

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City of Fort Collins NISP DEIS Comments
September 10, 2008
3a. City Drinking Water Sources
The DEIS underestimates the effects that NISP will have on the: quality of water that the City
uses for drinking. Glade Reservoir would be filled with runoff season high flows in the Cache la
Poudre River, water that has much higher levels (almost twice as high on average) of Total
Organic Carbon (TOC) as the Colorado-Big Thompson (C-BT) water stored in Horsetooth
Reservoir. TOC is of central importance to water supplies, because it reacts with the chlorine
necessary to treat water to form cancer-causing agents called disinfection byproducts. The levels
of these disinfection byproducts allowed in public drinking waiter are limited by the federal
Environmental Protection Agency (EPA) to protect human health. The City already expends
considerable effort and resources to remove TOC as part of the treatment process.
Under the NISP proposal, much of the high TOC water from the Glade Reservoir would be
piped to Horsetooth Reservoir and released close to the City's water treatment facility intake. It
would increase TOC levels for the raw water the City treats, degrading the drinking water
supplies of the City. In order to meet federal drinking water standards, the City may have to
further upgrade its drinking water treatment systems, which could cost in excess of $90 million
in capital costs and almost $3 million per year for operations.
The DEIS underestimates this threat to the City's drinking water. For example, the DEIS relies
on analysis that underestimates the TOC levels of the water that will fill Glade Reservoir and be
piped into Horsetooth Reservoir. The best available information indicates that Glade water
would have long-term average TOC levels of at least 5.5 mg/I,, (milligrams per liter) almost
twice the 2.9 mg/L level of Horsetooth. The DEIS then relies on the unrealistic assumption that
the high-TOC water from Glade would be completely mixed with the rest of water in Horsetooth
Reservoir and diluted before being used by the City, even though the Glade water would be
delivered on the north end of Horsetooth right next to the City's intake.
Because high TOC levels can produce potentially cancer-causing contamination of the City's
drinking water and force huge costs on the City, the City manages its water supply so that high
levels of TOC in its water supply will be avoided. However, the DEIS fails to provide any
meaningful analysis of these impacts or any guarantees they would be avoided, minimized and
mitigated. Instead, only vague and unreliable assertions are made that NISP's proponents might
examine some mitigation in the future. These assertions do not meet the requirements of the
Clean Water Act and NEPA.
3b. Water Quality Impacts to the Cache la Poudre River
NISP will have serious effects on the water quality in the Cache la Poudre River that are not
adequately addressed in the DEIS. The water quality of much of the River is already listed as
"impaired" by EPA due to fecal contamination and potentially toxic levels of other pollutants.
Reducing the flow of the River by 25% to 71% will reduce dilution of treated wastewater
treatment and other releases, making the water quality in the River much worse. It will also
increase the temperature of the River (which is harmful to fishy and has a detrimental affect on
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