HomeMy WebLinkAbout6 - Information Item, Potential for Run-of-River Operations for Lakewood HydroWATER RESOURCES ADVISORY BOARD
INFORMATION ITEM
To: Water Resources Advisory Board
From: Ned Williams, Public Works Director for Utilities
Carol Ellinghouse, Water Resources Coordinator
Date: November 20, 2006
RE: Information Item: Potential for Run-of-River Operations for Lakewood Hydro
EXECUTIVE SUMMARY
WRAB has been presented with a CEAP document for evaluation of the Betasso Water
Treatment Plant (WTP) Pipelines Project. The proposed project would include constructing a
new Betasso Penstock, converting the old Betasso Penstock into the Orodell Pipeline, and
converting the existing Orodell Pipeline into a discharge pipeline to carry excess raw water from
Betasso Hydro to Boulder Creek.
Lakewood Pipeline conveys water from Lakewood Reservoir to Lakewood Hydro located at the
Betasso WTP. Presently, all water run through Lakewood Hydro can only be discharged into the
treatment plant. This limits Lakewood Hydro's power generation potential to only the amount
derived from the city's municipal water deliveries through the Lakewood Pipeline. Therefore,
provision of a discharge pipeline through construction of the Betasso Pipelines Project would
also create the potential to increase generation at Lakewood Hydro. For evaluation of the Betasso
Pipelines Project, it was assumed that Lakewood Hydro operations are not altered and potential
revenues from "run-of-the-river" operation of Lakewood Hydro were not included in that
economic analysis. However, WRAB has requested information on the potential amount of
additional Lakewood Hydro generation possible with run-of-the-river operation to evaluate it as
an operational change separate from the evaluation of the Betasso Pipelines Project.
Limits on additional generation at Lakewood Hydro from run-of-the-river operations are set by
availability of water in North Boulder Creek at the same time as there is any additional capacity
in Lakewood Pipeline. Additional diversions are also limited by the city's contract with the
Colorado Water Conservation Board (CWCB) to provide instream flows below Lakewood
Reservoir. Therefore, this additional "run-of-the-river" generation potential is very small and
occurs irregularly.
The potential for additional generation at Lakewood Hydro created by a discharge pipeline at
Betasso WTP would only occur in some months and in some years. Additional generation will
not likely be possible in December, January, and July at all. Additional water diverted out of
North Boulder Creek for run-of-river operations would most often be an added 2 to 4 cubic feet
per second (cfs) and would not drop streamflow below minimum instream flow levels. Over a
period of 50 years, run-of-river operations at Lakewood Hydro could generate an additional
25,600 megawatt-hours (MWh) of electricity at a present worth value to the city of $229,000 and
offset the burning of 13,200 tons of coal.
BACKGROUND
General goals for the city's Utilities Department are:
• Management of facilities to increase the reliability of the municipal water supply system;
• Generation of hydroelectric power where feasible to maximize the city's generation of
clean, renewable energy and power sale revenues while maintaining hydroelectric power
production as a by-product of a water supply system driven by municipal water demand,
and;
• Estabiishing and maintaining instream flows in North and Middle Boulder Creeks and
Boulder Creek.
Boulder's Hvdroelectric Generation
The city has developed the environmentally and economically feasible hydroelectric generation
potential in its raw water delivery system. This potential exists because of lazge changes in
elevation between the ciry's diversion points and delivery points for its municipal water
pipelines. The city's Silver Lake Watershed and Middle Boulder Creek municipal water
deliveries generate hydroelectricity at the Silver Lake, Lakewood and Betasso Hydroelectric
Plants above the Betasso WTP. After the water is treated, it generates additional electricity at
four small hydroelectric plants on the treated water system below Betasso WTP. Electricity is
also generated from water retumed to Boulder Creek at the old Boulder Canyon Hydro Plant that
the city acquired from Xcel in 2001. The generation capacity for each plant depends on available
flow, turbine flow limits, gross head, head loss, and equipment efficiency. Available flow is set
by the demand for municipal water supply in Boulder. Much of the generation potential in the
Boulder water system results from high municipal water demand during the summer months.
Lakewood Hvdro
Lakewood Pipeline conveys water from Lakewood Reservoir located on North Boulder Creek
near Nederland to Lakewood Hydro located at the Betasso WTP. Lakewood Hydro was put into
operation in July 2004 following the reconstruction of Lakewood Pipeline. At present,
Lakewood Hydro is limited to the power generation possible from the ciry's municipal water
deliveries through the Lakewood Pipeline because all water run through Lakewood Hydro can
only be discharged into the treatment plant.
The proposed Betasso Pipelines Project would construct a discharge pipeline from Betasso WTP
to Boulder Creek and install the Tram Hill PRV. The discharge pipeline will be designed to
draw water from the joint dischazge bay for both Betasso and Lakewood Hydros. This will
create the potential to carry flows from both Betasso and Lakewood Hydros that are in excess of
needs at Betasso WTP to Boulder Creek. Therefore, provision of a discharge pipeline would also
create the potential to increase generation and hydropower revenues from Lakewood Hydro with
no change in the existing turbine and generator. Lakewood Hydro operates between 3 and 31 cfs
with a net operating head of 1,554 feet at full load.
All reservoir storage capacity in the North Boulder Creek system is dedicated to municipal water
suppty and is not available for power generation purposes only. As a result, any additional
generation at Lakewood Hydro would come from run-of-the-river operations. Water flowing in
North Boulder Creek at Lakewood Reservoir that must be delivered to senior water users
downstream would be diverted into Lakewood Pipeline, through Lakewood Hydro, and then
returned to Boulder Creek at Orodell above the other water users.
ANALYSIS
Instream Flow Amounts Needed for Habitat
The instream flow needs for the reach of North Boulder Creek below Lakewood Reservoir have
been extensively studied. Environmental studies of this stream reach were conducted during the
Lakewood Pipeline reconstruction permitting process and also in suppoR of the instream flow
filings made by the CWCB.
In 1992, Chadwick and Associates completed a study far the Environmental Impact Statement
(EIS) process done by the US Farest Service (USFS) for an easement for Lakewood Pipeline.
This study used the Instream Flow Incremental Methodology (IFIM) to evaluate the habitat
needs for the trout species and macroinvertebrates found in North Boulder Creek. This method
collects information on habitat chazacteristics within the studied stream segments to determine
the percentage of habitat types such as riffle, run, or pool. This information is combined with
historic hydrologic data to determine which period of the year results in the lowest habitat levels
for fish. Decisions on minimum flow levels to be maintained in each season can then be made.
The report states, "In Rocky Mountain streams the bottlenecks to fish populations generally
occur during extreme flow conditions, either the high flow period in late spring or the low flow
period in winter." Also, "Habitat levels for trout and macroinvertebrates peak at intermediate
flows with lower levels of habitat at high and low flows." If high flow periods are the ]imiting
life stage for the studied species, then "developing a minimum flow regime to benefit the non-
limiting life stage will have no resulting effect on the fish population as there is already excess
habitat for these life stages relative to the limiting life stage."
Fish sampling showed the dominant species in North Boulder Creek to be brook trout and
rainbow trout. Fry of both species are vulnerable to being displaced by high spring runoff flows.
Sampling demonstrated that fry and juvenile trout were relatively numerous in North Boulder
Creek and adult fish were limited. This supported the study conclusion that adult winter survival
of the fish during low flow periods is the limiting life stage. The study stated that a minimum
winter flow of 0.3 cfs was needed below Lakewood Reservoir to meet the USFS criteria of
maintaining 40 percent of habitat for fish species. However, the minimum flow needed to
sustain macroinvertebrates was 1 cfs. The study recommended limiting high flow to the 70 to 80
cfs range because it would "result in suitable habitat conditions that would not limit the
enhancing efforts of increased winter flow." In other words, limiting high flows in the spring
would result in a habitat level equivalent to that achieved by increasing minimum winter flows.
Sufficient fry would survive the high flows to assure that the presence of the maximum number
of adult fish that the stream channel characteristics could support in the winter.
The high flow periods on North Boulder Creek do not contribute to limitations on fish
population. Spring peak flows are in the range of 65 to 75 cfs with the city's municipal water
diversions. The city's diversions during high flow periods in the spring and early summer help
bring habitat into the most desirable range for survival of fry and juvenile fish. The city operates
its Boulder Creek exchange, where Boulder Reservoir water is substituted for additional
diversions in the upper Boulder Creek watershed, during high streamflow periods. The exchange
can only occur when streamflows are high enough to satisfy all other diverters between the upper
watershed and the Boulder Reservoir outlet. The exchange reduces peak flow levels in the
spring and early summer and, therefore, serves to enhance habitat.
In 1993, Colorado Division of Wildlife (DOW) performed an evaluation of instream flow needs
for North Boulder Creek below Lakewood Reservoir using a methodology called R2-Cross. This
work was done in support of CWCB instream flow filings for the creek. The DOW also found
that rainbow and brook trout were the dominant species based on sampling done by DOW from
1988 to 1991. The DOW found that a minimum flow of 5 cfs from April 1 to September 30 met
all three criteria DOW believed necessary to preserve fish habitat in this reach. A lower winter
flow requirement of 2 cfs was set based on the DOW biological recommendation.
These studies were used to establish the flow levels for the city's commitment to provide the
CWCB with water for instream flow purposes. In 1990 and 1992, the city entered into contracts
with the CWCB to donate use of city water rights to supplement available streamflow to reach
the desired minimum instream flow levels. The city and the CWCB joindy applied to Water
Court for a decree that would add instream flow as an allowed use for the city's donated water.
North Boulder Creek is a gaining stream, so it was determined that'minimum streamflow levels
could be achieved through the city's provision of 1.5 cfs at Lakewood Reservoir in winter. In
the summer, the water rights donated by the city have priority dates ranging from 1859 to 1862
which is sufFiciently senior that the rights typically yield about 5 cfs.
Channel Maintenance Flows
During the USFS EIS process, the question of a need for channel maintenance flows for purposes
of maintaining sediment transport and preventing vegetation encroachment was raised. A study
was performed by Resource Consultants and Engineers to address the question in November
1992. The study found that the channel maintenance flow needs associated with lower elevation
plains streams were not applicable to a stream with the characteristics of North Boulder Creek
for several reasons.
First, the valley and channel containing North Boulder Creek was not initially formed by flowing
water, but by glacial movement. Later, huge amounts of water were released when a natural dam
created by glacial deposits gave way. Flow levels typically seen today are much smaller than
these pre-historic channel-forming events. Second, the glacial origin of the North Boulder Creek
channel has created a step-pool configuration that is "formed by clusters of lazge rocks that can
only be transported by extreme flow events." "Coarse sediments that form the beds of the upper
elevation channels are unlikely to experience flows sufficient for their mobilization" because
snowmelt-dominated streams have little difference in flow between normal high spring flows and
more frequently occurring flood events (in the range of 20 [0 100 year recurrence intervals.) In
contrast, flows in rainfall-dominated streams at ]ower elevations during flood events can greatly
exceed average flows. Third, the surrounding geologic landforms supply much less fine
sediment to North Boulder Creek than the existing stream channel is capable of carrying.
The report concludes that "North Boulder [Creek] falls into the category of certain mountain
streams whose form is dominated by factors other than the interaction of frequently occuiring
flows and the channe] boundary materials....The overbank areas along North Boulder Creek are
not the product of floodplain accretion, but rather the product of the stream incising into the
valley floor materials that, for the most part, were not deposited by the range of frequentty
occurring flows" seen today. "The material being transported is significantly finer than that
making up the bed. There is considerable field evidence that the reaches of North Boulder Creek
downstream of Lakewood Reservoir have the capacity to transport significandy more of the
relatively small caliber sediment than is being supplied from upstream....A reduction in flow in
such streams will not result in significant aggradation and loss of channel capacity." Therefore,
artificial provisions for channel maintenance flows are not necessary.
Potential for Run-of-the-River Oaeratioas at Lakewood Hvdro
Additional generation potential at Lakewood Hydro is limited by the availability of water in
North Boulder Creek occumng at the same time as there is any additional capacity in Lakewood
Pipeline above that needed for municipal water deliveries. It is also limited by the city's contract
with the CWCB to provide instream flows below Lakewood Reservoic Therefore, this
additional run-of-the-river generation potential is very small and occurs irregularly.
Information generated from use of the Boulder Creek hydrologic model (developed far the city
by Hydrosphere) shows that the months with the highest potential for additional generation at
Lakewood Hydro would be March, August and September and would occur about 35 years out
of every 49 years. Run-of-river operations in February through June, October, and November
could occur about every 6 to 11 years out of every 49 years. Additional generation will not
likely be possible in December, January, and July. Additional water diverted out of North
Boulder Creek at times when run-of-river operations were possible would most often be in the
range of an additional 2 to 4 cubic feet per second (cfs) and at no time would drop streamflow
levels below the minimum instream flow levels set by the CWCB. (See Attachment A-Table
of Potential Change in Streamflow and Attachment B-Charts of Potential Run-of-River
Operations.)
The power sales contract between the city and Xcel that includes Lakewood Hydro contains
provisions for payment to the city for every kilowatt-hour (kWh) that is generated. Additional
generation at Lakewood Hydro from run-of-the-river operations would increase generation
payments. An economic analysis of the potential increase in revenue was completed based on
the same assumptions used in the Betasso Pipelines Project CEAP. Assumptions were a 50-year
project ]ife (the typical life assumed for economic analyses of hydroelectric projects), a present
worth discount rate of 4 percent, and an energy payment rate of $0.02 per kW-hr.
Over a period of 50 years, Lakewood Hydro could generate an additional 25,600 megawatt-hours
(MWh) of electricity to be sold to Xcel at a present worth value to the city of $229,000 based on
run-of-river operations. This wouid offset the burning of 13,200 tons of coal to generate a like
amount of electricity at a conventional coal-fired powe~plant, reduce SOz emissions by 20 tons,
reduce NOX emissions by 40 tons, and reduce COZ emissions by 13,300 tons.
CONCLUSION
There is not very much potential for run-of-the-river operations at Lakewood Hydro after a
discharge pipeline is installed at Betasso WTP. Occasions when there is additional water in
North Boulder Creek above the amount needed for both instream flows and municipal diversions
at times when there is also capacity remaining in Lakewood Pipeline are rare. Even so, pursuing
the potential for additional generation could produce economic and environmental benefits for
the city from the hydropower without negative environmental impact to North Boulder Creek.
Attachment A
Table of Potential Change in Streamflow
Potential Quarter Month Change in Streamflow in N. Boulder Creek at Lakewood
Reservoir from Run-of-River Operation w/ Discharge Line Available
1950 1951 1952 1953 1954 1955 1956 1957 1958
1959
1960
1961
1-Oct -1.66 -0.08 0.00 -4.18 -6.38 -0.84 0.00 0.00 0.00 0.00 -2.54 0.00
2-Oct -0.02 -2.54 0.00 -5.63 -5.81 0.00 0.00 0.00 0.00 0.00 -1.72 0.00
3-Oct 0.00 -1.91 0.00 -6.70 -5.71 0.00 0.00 -0.02 -0.66 0.00 -1.17 0.00
4-Oct 0.00 -2.18 0.00 -729 -2.54 0.00 0.00 -0.38 0.00 0.00 -0.81 0.00
1-Nov 0.00 -0.39 -1.59 -6.38 0.00 -0.33 0.00 0.00 0.00 0.00 0.00 0.00
2-Nov 0.00 -0.77 0.00 -5.81 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Nov 0.00 -124 0.00 -5.71 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Nov 0.00 0.00 0.00 -2.54 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
t-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Feb 0.00 0.00 0.00 0.00 0.00 0.00 0 00 0.00 0.00 0.00 0.00 0.00
2-Feb 0.00 0.00 0.00 0.00 0.00 0.~0 O.OQ 0.00 0.00 0.00 0.00 0.00
3-Feb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Feb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
t-Mar 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Mar 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Mar 0.00 0.00 0.00 0.00 0.00 -0.83 0.00 0.00 0.00 0.00 0.00 0.00
4-Mar 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 -425
1-Apr 0.00 0.00 -0.48 0.00 0.00 0.00 -1.89 -4.41 0.00 -1.55 0.00 0.00
2-Apr 0.00 0.00 0.00 0.00 0.00 -1.43 -4.41 -4.41 0.00 -7.00 0.00 0.00
3-Apr 0.00 0.00 0.00 0.00 0.00 -4.41 -0.23 -4.41 0.00 -4.41 0.00 0.00
4-Apr 0.00 0.00 0.00 0.00 -425 -2.88 -4.25 -425 3.07 -425 -4.25 0.00
t-May 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-May 0.00 -4.47 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-May -4.41 -4.41 -4.41 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-May -3.24 -425 -425 -425 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Jun 0.00 0.00 0.00 0.00 0.00 -120 0.00 0.00 0.00 0.00 0.00 0.00
2-Jun 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Jun 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Jun 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Aug 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Aug 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 -0.33
3-Aug 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Aug 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Sep 0.00 0.00 0.00 0.00 -4.43 0.00 -2.16 -3.17 0.00 -6.82 0.00 -1.66
2-Sep 0.00 0.00 0.00 0.00 -4.93 0.00 -1.59 -1.53 0.00 -6.07 -0.33 0.00
3-Sep 0.00 0.00 0.00 0.00 -2.47 0.00 0.00 -0.46 0.00 -4.11 0.00 0.00
4-Sep 0.00 0.00 0.00 0.00 -1.82 0.00 -0.59 -0.45 0.00 0.00 0.00 0.00
Potential Quarter Month Change in Streamflow in N. Boulder Creek at Lakewood
Reservoir from Run-of-River Operation w/ Discharge Line Available
1962 1963 1964 1965 1966 1967 1968 1969 1970
1971
1972
1973
1-Oct 0.00 0.00 0.00 0.00 0.00 -0.90 0.00 0.00 0.00 0.00 0.00 0.00
2-Oct 0.00 0.00 0.00 0.00 0.00 -0.77 0.00 0.00 0.00 0.00 0.00 0.00
3-Oct 0.00 0.00 0.00 0.00 0.00 -0.96 0.00 0.00 0.00 0.00 0.00 0.00
4-Oct 0.00 0.00 0.00 0.00 0.00 -1.31 0.00 0.00 0.00 0.00 0.00 0.00
1-NOV 0.00 0.00 0.00 0.00 0.00 -1.72 0.00 0.00 0.00 0.00 0.00 0.00
2-NOV 0.00 0.00 0.00 0.00 0.00 -1.97 0.00 0.00 0.00 0.00 0.00 0.00
3-Nov 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Nov 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Feb 0.00 0.00 0.00 -5.52 0.00 0.00 -1.81 0.00 0.00 0.00 0.00 0.00
2-Feb 0.00 0.00 0.00 -2.56 0.00 0.00 -4.20 0.00 0.00 0.00 0.00 0.00
3-Feb 0.00 0.00 0.00 -4.15 0.00 0.00 0.00 0.00 0.00 -0.76 0.00 0.00
4-Feb 0.00 0.00 -2.85 -7.17 0.00 0.00 -4.15 0.00 0.00 -5.44 0.00 0.00
1-Mar 0.00 0.00 -4.41 0.00 -5.65 0.00 0.00 0.00 0.00 -4.41 -4.41 0.00
2-Mar 0.00 -4.41 -4.41 -4.41 -025 0.00 0.00 0.00 0.00 -5.15 -7.00 0.00
3-Mar -0.61 -5.21 -4.41 -4.41 -4.41 -4.41 0.00 -4.41 0.00 -7.00 -7.00 0.00
4-Mar -4.25 -3.35 -4.25 -3.64 -3.93 -4.25 0.00 -4.25 -4.25 -7.06 -4.25 -2.35
1-Apr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Apr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Apr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Apr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-May 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-May 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-May 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-May -1.30 0.00 0.00 0.00 -0.14 0.00 0.00 -2.30 0.00 0.00 0.00 0.00
1-Jun 0.00 0.00 -120 0.00 0.00 0.00 0.00 0.00 -1.74 -1.49 -1.07 -1.39
2-Jun 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Jun 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Jun 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Aug -6.38 0.00 0.00 0.00 -4.05 0.00 -5.50 -8.40 0.00 0.00 0.00 0.00
2-Aug 0.00 0.00 -5.88 0.00 -2.98 0.00 -4.81 -0.90 -1.66 0.00 0.00 -5.00
3-Aug 0.00 0.00 -4.62 -8.21 -1.78 0.00 3.86 -827 -5.06 0.00 -0.39 -6.07
4-Aug -3.33 0.00 -4.12 -6.71 -225 -2.75 -2.68 -3.47 -4.63 0.00 0.00 0.00
1-Sep -2.66 0.00 -3.23 -5.50 -2.10 -5.18 -0.65 -6.63 -2.16 -5.12 -3.61 -2.10
2-Sep -1.59 0.00 -2.35 -3.67 -1.91 0.00 0.00 -5.37 -0.46 0.00 -3.10 0.00
3-Sep -0.95 0.00 -1.75 -225 -1.67 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Sep 0.00 0.00 -1.60 0.00 -1.39 0.00 -0.23 0.00 0.00 0.00 0.00 0.00
Potential Quarter Month Change in Streamflow in N. Boulder Creek at Lakewood
Reservoir from Run-of-River Operation w/ Discharge ~ine Available
1974 1975 1976 1977 1978 1979 1980 1981 1982
1983
1984
1985
1-Oct 0.00 0.00 0.00 0.00 -0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Oct 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Oct 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Oct 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Nov 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Nov 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-NOV 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Nov 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
t-Feb -2.56 0.00 0.00 0.00 -5.52 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Feb -4.14 0.00 0.00 0.00 -5.71 0.00 0.00 0.00 0.00 -4.58 0.00 0.00
3-Feb -3.93 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Feb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Mar 0.00 0.00 -4.41 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Mar 0.00 0.00 -4.41 0.00 -0.29 -4.41 -2.50 -0.10 0.00 0.00 0.0~ 0.00
3-Mar -4.41 0.00 -4.41 -4.41 0.00 -2.84 -4.41 -2.44 0.00 0.00 -4.41 0.00
4-Mar -4.25 -0.69 -425 0.00 -4.25 -4.25 -4.25 -6.67 -6.02 0.00 -3.86 0.00
t-Apr o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo
2-Apr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Apr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Apr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-May 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-May -1.51 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-May 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-May 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 -2.30 0.00 0.00 0.00
1-Jun 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3.47 0.00 0.00 0.00 0.00
2-Jun 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Jun 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Jun 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Aug -4.05 -2.79 -6.70 -6.95 -4.74 -0.84 -1.40 -2.29 -2.16 -1.66 -0.14 0.00
2-Aug -5.18 -1.97 0.00 -5.63 -5.75 -0.52 -1.40 -1.28 0.00 0.00 0.00 -3.99
3-Aug 0.00 -3.36 -7.89 -2.35 -3.80 -1.59 0.00 0.00 -0.14 0.00 0.00 -3.17
4-Aug 0.00 -1.67 0.00 -1.67 0.00 -2.97 -0.09 0.00 0.00 0.00 0.00 -2.03
1-Sep -5.56 -2.54 -6.26 -0.71 -2.41 -3.48 0.00 0.00 -1.59 -2.41 0.00 -0.77
2-Sep -5.12 -2.29 -4.87 0.00 -1.09 -4.05 0.00 0.00 -1.97 -3.67 0.00 0.00
3-Sep 0.00 -1.53 0.00 0.00 -0.45 -3.98 -0.38 0.00 -1.82 -4.12 0.00 0.00
4-Sep 0.00 0.00 0.00 0.00 0.00 0.00 -1.17 0.00 -0.38 0.00 0.00 0.00
Potential Quarter Month Change in Streamflow in N. Boulder Creek at Lakewood
Reservoir from Run-of-River Operation w/ Discharge Line Available
1986 1987 1988 1989 1990 1991 7992 1993 1994 1995 1996 1997
i-occ o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo
2-Oct 0.00 0.00 0.00 0.00 0.00 0.00 -0.52 0.00 0.00 0.00 0.00 0.00
3-Oct 0.00 0.00 0.00 0.00 0.00 0.00 -0.58 0.00 0.00 0.00 0.00 0.00
4-Oct 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Nov 0.00 0.00 0.00 -1.97 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Nov 0.00 0.00 0.00 -1.91 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Nov 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Nov 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Dec 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0 00 0.00
4-Jan 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Feb 0.00 0.00 0.00 0.00 0.00 3.19 0.00 -029 0.00 0.00 0.00 -0.73
2-Feb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Feb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Feb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 -0.40 0.00 0.00 0.00
1-Mar 0.00 0.00 0.00 0.00 0.00 -2.84 0.00 0.00 -4.41 0.00 -4.41 0.00
2-Mar -7.00 0.00 0.00 -1.49 -4.41 0.00 0.00 0.00 -4.41 -4.41 -4.41 0.00
3-Mar -6.15 -4.41 -4.33 -4.41 0.00 -4.41 -4.41 -1.68 -4.41 -4.41 -4.41 0.00
4-Mar -4.25 -4.25 -2.56 -425 -4.25 -2.42 0.00 -4.25 -4.25 -425 -4.25 0.00
1-Apr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Apr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Apr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Apr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
t-May 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-May 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 -0.69 0.00
3-May 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-May 0.00 0.00 -2.38 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Jun 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Jun 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Jun 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Jun 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
2-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4-Jul 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1-Aug 0.00 -0.02 0.00 -1.78 -1.66 -7.52 -0.52 -0.21 -3.92 0.00 -1.91 0.00
2-Aug 0.00 0.00 0.00 0.00 -1.66 -8.34 -0.58 -1.91 -5.63 0.00 -0.77 0.00
3-Aug 0.00 -6.95 0.00 -0.14 -1.02 -6.57 0.00 -1.02 -7.26 0.00 0.00 0.00
4-Aug -0.09 -5.56 -1.31 -0.16 -0.45 -4.77 -1.75 0.00 -6.79 0.00 -0.52 -0.16
1-Sep 0.00 -2.03 -7.58 -1.97 0.00 -1.91 0.00 0.00 -827 -11.17 -0.21 -0.58
2-Sep 0.00 0.00 0.00 -2.66 0.00 0.00 0.00 0.00 -7.96 -5.56 -0.58 -0.46
3-Sep 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 -5.63 -0.74 0.00
4-Sep 0.00 0.00 0.00 0.00 0.00 0.00 0.00 -0.02 0.00 3.76 -0.52 0.00
Quarter Greatest # years out of 49 avg reduction for
Month Reduction possible to do years when run-of-
Average (cfs) run-of-river river is possible (cfs)
1-Oct -0.34 -6.38 S 2.07
2-Oct -0.35 -5.81 7 2.43
3-Oct -0.36 -6.70 8 2.21
4-Oct -0.30 -729 6 2.42
1-Nov -0.25 -6.38 6 2.06
2-Nov -021 -5.81 4 2.62
3-Nov -0.14 -5.71 2 3.47
4-Nov -0.05 -2.54 1 2.54
t-Dec 0.00 0.00 0 0.00
2-Dec 0.00 0.00 0 0.00
3-Dec 0.00 0.00 0 0.00
4-Dec 0.00 0.00 0 0.00
1-Jan 0.00 0.00 0 0.00
2-Jan 0:00 0.00 0 0.00
3-Jan 0.00 0.00 0 0.00
4-Jan 0.00 0.00 0 0.00
1-Feb -0.40 -5.52 7 2.81
2-Feb -0.43 -5.71 5 4.24
3-Feb -0.18 -4.15 3 2.95
4-Feb -0.54 -7.17 6 4.39
t-Mar -0.77 -5.65 9 4.20
2-Mar -1.39 -7.00 18 3.77
3-Mar -2.40 -7.00 28 4.20
4-Mar -2.75 -7.06 32 4.21
1-Apr -0.17 -4.41 4 2.08
2-Apr -0.35 -7.00 4 4.31
3-Apr -0.27 -4.41 4 3.37
4-Apr -0.55 -4.25 7 3.88
1-May 0.00 0.00 0 0.00
2-May -0.14 -4.41 3 2.21
3-May -027 -4.41 3 4.41
4-May -0.50 -425 9 2.71
1-Jun -0.24 -3.47 7 1.65
2-Jun 0.00 0.00 0 0.00
3-Jun 0.00 0.00 0 0.00
4-Jun 0.00 0.00 0 0.00
1-Jul 0.00 0.00 0 0.00
2-Jul 0.00 0.00 0 0.00
3-Jul 0.00 0.00 0 0.00
4-Jul 0.00 0.00 0 0.00
1-Aug -1.58 -8.40 24 3.22
2-Aug -1.35 -8.34 21 3.15
3-Aug -1.71 -8.27 22 3.80
4-Aug -1.22 -6.79 23 2.61
1-Sep -2.42 -11.17 34 3.49
2-Sep -1.50 -7.96 25 2.95
3-Sep -0.66 -5.63 15 2.15
4-Sep -024 -3.76 11 1.08
Attachment B
Charts of Potential Run-of-Kiver Operations
Potential years out of 49 that streamflow in North Boulder Creek at Lakewood
Reservoir may be reduced by run-of-river hydro operations
(flows are not reduced below minimum instream flow levels)
rn
e
`o
5
0
N
N
N
]+
O
O
Z
Estimated Potential for Additional Run-of-River Operation in Water Year
2005
so.oo _ . ,
~o.oo
so 00
so oa
a
c
0
y 4~.00
y
w
a
~ 30 00
U
a
3 20.00
U
i o.oa
0 00 _ _ _ .
-io.oo
~
Oct Nov
~ Dec
~ Jan I Feb ' Mar Apr May Jun Jul ~, Aug ~ Se~
~ Est. Avg. Flow at Lakewood 2004-OS I 4 90 5 40 1 80 3.50 I 2 80 2-SO 7.30 ~. 20-40 71 10 45 40 ' 17 90 ~ 3J0 ,
~
~ tlow remaining atter ROR 2004-05 I 3.40
~ 4.05 1 80 3 50 i 2 00 2-50 523 j 19.39 70.69 ' 45.40 15.85 i 3.70
i
~r~F~t nin-nf-rivar nntential 2004-OS ~
1.50
!
1.35
0.00
0.00
~, 0.80
0.00
2.0~
I 1.01 i
0.41 0.00
2A5 j
0.00 I
~, c~ ~, ~~c ~m ~,~~ pQ ~,~~ ~~c ~3 ~ ~c
Month
Estimated Potential for Additional Run-of-River Operation in Water Year
1974
130 ~ _ _
110
9~ ~
v
~ ~~ I
m
y
i
~
`m
a
d 50
V
a
U I
30 ! j
10
-10
'
Oct Nov Dec I Jan Feb Mar 14 Apr May ' Jun Jul Aug
~ Sep
~ Est. Avg. Flow at Lakewood 1973-74 I 2 2 2 2 4 7 7.2 ` 5 11.4 ' 109.6 1 70.8 15.6 10.1
~ flow remaining after ROR 1973-74 2 2
~ 2 2 ~ 2 5 5 11.02 109.6 I 70.8 13.29 7.43
rEstrun-of-river potential 1973-74 0 0
I 0 0 2.7 22 0 0.38 0 I 0 1 2.31 ' 2.67
i,o
ioo
90
80
~ 7O
0
~ 60
~.
~ 50
U
4
v 40
30
20
10
0
38292 38322 38353 38384 38412 3t3443 384T3 ?Fi5i~1 38534 38G65 38b96 38261
I ~ Est, Flow below Lakewood 1995-96 Oflow remaining after ROR 1995-96 ?i Est. run-of-river potenlial 1995-96 ~
Estimated Potential for Additional Run-of-River Operation in Water Year
1996