Meeting Minutes
October 21, 1999
2:30 P.M.
University of Idaho McClure Hall #207
Sue Hinz (Pullman)
2.
PRESENTATION – Water Use on the Palouse and Upcoming
Challenges of the PBAC (J. McKenna)
The presentation was divided
into three parts: (1) an introduction and overview of the Palouse groundwater
basin, (2) a review of the water level and pumpage data presented in the 1998
Palouse Basin Water Use Report, and (3) upcoming challenges facing the
PBAC. The presentation is summarized
below:
(1)
The Palouse groundwater
basin consists of two aquifers: the Wanapum Basalt aquifer is the shallow aquifer
that is tapped by wells less than 200 or so feet deep and produces less than
1,500 gallons per minute (gpm), and the Grande Ronde Basalt aquifer, which is
tapped by wells deeper than 200 or so feet, and produces up to 3,000 gpm.
i.
With the exception of
Moscow Well Nos. 2 and 3, all municipal wells pump from the Grande Ronde. Historically, water levels in wells in the
Wanapum have stabilized or increased in response to decreased pumping from the
Wanapum. For the last 50 years, water
levels in Grande Ronde wells have consistently decreased by 1 to 2 feet per
year regardless of pumping rates from this aquifer.
ii.
A cross section
compiled by J. Bush, UI geology professor, indicates that both aquifers are
laterally inhomogeneous, with the eastern edge of the basin in Moscow
characterized by more than 50 percent sedimentary layers in the
subsurface. In contrast, the subsurface
in Pullman is 90 percent or greater basalt units, with less than 10 percent
sedimentary layers. The sedimentary
layers are much more abundant in both aquifer units beneath Moscow. These sediments were derived from the nearby
mountains to the east and are iron rich.
Dissolution of these sediments is the likely cause for the high iron and
manganese concentrations in some wells in Moscow (both Grande Ronde well No. 8,
and Wanapum wells No. 2 and 3).
iii.
The rationale behind
the voluntary pumping limits contained in the 1992 Groundwater Management Plan
(GWMP) was reviewed. As part of the
GWMP, each entity (except Whitman County, where use was not quantified) agreed
to limit pumping to a maximum of 125 percent of the average pumping rate during
the 1981-1985 base period, and would increase their pumping by no more than 1
percent each year (computed based on a five-year moving average). The reason for these limits is that the US
Geological Survey (USGS) groundwater model for the basin (Lum and others, 1990)
predicted that water levels in wells in the basin would stabilize if the rate
of pumping in the basin were stabilized, and did not increase annually. The model predicted that if pumping in the
basin were stabilized at 125% of the average of the 1981-1985 base period, then
water levels (drawdown) would stabilize at approximately 25 feet lower than was
observed during the base period.
(2)
Summary of findings
from 1998 Palouse Basin Annual Water Use Report:
i.
Water use in 1998 was
2.7 billion gallons split among the four primary entities as follows: Pullman
33%, Moscow 34%, UI 12%, WSU 21%. Per
capita consumption is equal in both Moscow and Pullman, if the populations of
the universities are included. There is
no simple way to separate out university populations from the total city
population to get a per capita estimate for each of the four entities. Pullman remains below the 125% ceiling and
the 1% annual increase limit, however its water use is increasing annually. WSU
remains below both limits, and has decreased water use every year for the last
10 years or so. UI’s water use is also
below both limits and on average, its water use has also been decreasing each
year. Moscow’s water usage was adjusted
after learning that two of its well meters were reading high (see Item 5A,
below), and the adjusted data indicates that Moscow is just below the 125%
ceiling, but has exceeded the 1% growth limit in each of the last 4 years. If pumpage increases next year in Moscow,
the 125% ceiling will likely be exceeded.
At the average annual, basin-wide rate of increase (approximately 0.6%),
the basin will reach the 125% ceiling in 2022.
If population growth continues in the basin (which is likely), PER
CAPITA water use in the basin must be reduced in order to not exceed the
pumpage limits.
ii.
Based on the data that
is available from municipal wells, Water levels in Grande Ronde wells continue
to decline at a rate of 1-2 feet per year.
Data for Wanapum wells (Moscow Well Nos. 2 and 3) indicate that water
levels are increasing or have stabilized.
(3)
Challenges Facing PBAC:
i.
Problem: Water levels
continue to decline in most municipal (Grande Ronde) wells. PBAC Challenge: To develop and implement
a sustainable, long-term pumping scenario.
This effort will likely involve significant costs in research, pilot
testing of possible alternatives, and ultimately, in implementation.
ii.
Problem: Growth in the basin continues and the growth
rate may escalate. PBAC
Challenge: Reduce per capita water use
and/or be willing to pay for a supplemental water supply. This effort will involved educating the
public and implementing efficient water use and conservation practices.
(4)
Questions:
i.
M. Workman wondered if
this presentation would be given to the community in other forums. J. McKenna
stated that with some minor modifications, that would be appropriate. C. Benjamin suggested making it less technical.
3.
Groundwater Management Plan Update
A) PBAC Goals and Strategies
A draft of updated goals for the Groundwater
Management Plan was discussed by the
Committee in 1997 and this draft was distributed to the members. The following goals were discussed:
·
Monitor the progress of the Osiensky-Keller (O-K) project
(M. Workman);
·
Attempt to obtain additional funding for supplemental
project work from Idaho State and funding for recycled water reuse from
Washington State (L. Kirkland)
·
Conservation and education (L. Kirkland)
·
Consider offering incentives for pumping from the shallow
aquifer (L. Kirkland)
B) Entities’ Action Plan
Compliance Reports
University of Idaho, Washington State University,
Pullman, and Moscow submitted compliance reports reporting on the status of
each of the entity’s Action Items in the Groundwater Management Plan. These will be summarized and presented at
the next meeting.
4. Reports and Announcements:
A) PBAC Budget Review- no questions
B) EPA Wetlands Grant - L. Kirkland stated that no local
group will pursue this funding for this fiscal cycle.
C) Community Relations - J. McKenna reported that
she has been posting PBAC information on a Moscow community discussion group (vision2020@moscow.com) and she
and T. Townsend met with Roger Kendall, editor of the Moscow-Pullman Daily
News, to discuss increasing coverage of PBAC.
A website has been started at http://www.uidaho.edu/~pbac, but J.
McKenna needs additional help to further develop the web site.
5. New Business
A)
Moscow Water Use
T. Scallorn summarized the results of an investigation he did into well metering and Moscow’s water use at the request of PBAC. Several million gallons can be explained by the need to frequently flush hydrants (in response to customer complaints about discolored water), and the need to
backwash the filters at their green sand filtration plant due to the high iron and manganese content from Moscow's shallow aquifer wells. To Moscow's credit, they pump a fair amount of water (20 percent in 1997) from the shallow aquifer and have invested substantially to keep their filtration system up-to-date. Water levels in wells located in the shallow aquifer do not seem to be declining like those in the deeper one. The suggestion has been made by the PBAC that water use accounting should distinguish between pumpage from the shallow and the deep aquifer, and even to offer credits for pumping from the shallow aquifer, which seems to be recharged via precipitation.
In addition, Moscow has recently had all of their flow meters recalibrated by the manufacturer and found that several were reading high. Moscow estimates that these factors (flushing, backwashing, high meter readings) account for about 6 percent of their total water usage in 1997 (a total of 52 million gallons out of 870 million gallons). If this amount were subtracted, Moscow would be below the 125% ceiling. Copies of the report are available from Tom Scallorn or PBAC.
B)
Consumer Confidence Reports
The
EPA required that Consumer Confidence Reports (CCRs) summarizing water quality
be prepared by community water systems and distributed to customers by October
18, 1999, and annually thereafter. Each
community water system (UI, WSU, Moscow, Pullman) shared copies of its
report. No major water quality
violations were reported by any system.
Copies are available from individual water systems or through PBAC. L. Kirkland suggesting that these annual
reports are a good opportunity to incorporate conservation suggestions.
C)
Environmental Science Interns
L.
Kirkland stated that interns are available through several departments on
campus and could be used to complete projects for the Committee. Any ideas for use of interns should be
forwarded to Juliet McKenna.
6. Water-RElated Projects Update
This
will be a regular agenda item and updates on water-related projects by each
entity will be distributed periodically.
M. Workman stated that Pullman is planning on constructing Well No. 7
and has transferred a water right from an old well to this well.
7. Next meeting date
2:30 PM
Thursday, October 21, 1999
University of Idaho
McClure Hall Room 207
NOTE ROOM CHANGE
Respectfully Submitted,
Juliet M.
McKenna
Executive Secretary/Technical Advisor
These minutes are submitted in final form and have
been approved by the Committee.