Guy J' Gregory

1
Spokane Valley Rathdrum Prairie Aquifer
Study Interstate modeling, initiatives toward
integrated management
Presented by Guy J. Gregory Washington Dept. of
Ecology Spokane, WA
2
Spokane Valley Rathdrum Prairie Aquifer
3
Purpose and Goal

• The purpose of this project is to provide a
  scientific foundation for management of the SVRP
  aquifer. The study will culminate in the
  development of a numerical ground-water model
  that Washington and Idaho can use to
  cooperatively manage the SVRP aquifer and
  adjacent rivers and lakes

4
Why do you need to manage water here, anyway?
The thing that sets this region apart is our
infinite supply of clean water -My Eighth Grade
Earth Science Teacher
2001 Power Plant Proposals
5
(No Transcript)
6
(No Transcript)
7
Common concerns, uncommon solutions

• Pressures
• State Water management agency pressure.
• Local Government management planning processes
• WRIA, Kootenai County process
• Stakeholder/NGO cooperation
• Policy Advisory Committee
• Product.
• Three Party Memorandum of Agreement
• USGS participation, two-state study
• Results.
• Partnership of state water-management agencies
• Product-oriented investigation

8
Administrative Organization
9
(No Transcript)
10
(No Transcript)
11
Key Model Elements

• Conceptual model
• 3 Layers
• 1. Layer 1 The unconfined aquifer.
• 2. Layer 2 A confining bed of limited extent.
• 3. Layer 3 A confined aquifer of limited
  extent.

• Modflow Hydrologic Packages
• 1. Recharge (.RCH)
• 2. Well (.WEL)
• 3. River (.RIV)
• 4. Stream flow routing (.SFR)
• 5. General head boundary (.GHB)
• 6. Flow and head boundary (.FHB)

12
Model Grid
Uniform cells of size 1320 feet by 1320 feet.
13
Model Domain
14
May 8, 2007CenterPlaceSpokane Valley, WAWhat
did we learn?
15
The aquifer and the surface water of this region
are completely intertwined.
16
Lake Pend Oreille
Well 236
Well 234
90
92
94
96
98
00
02
04
In the vicinity of Lake Pend Oreille,
ground-water levels are controlled by lake level.
236
234
17
Spokane River near Otis Orchards
Well 60
J
A
S
O
N
D
J
A
S
O
N
D
J
F
M
A
M
J
2004
2005
In Spokane Valley, ground-water levels are
controlled by stage on the Spokane River.
gage
60
18
Regional Water Use
19
Where is most water used?
20
USGS stream gage at Greenacres
Spokane River at Barker Road Bridge
21
15 year Dataset on Regional Municipal and
Industrial Pumping
22
Patterns of Water Use
Gross Pumping from Data
Pumping Rate
Jan Feb Mar Apr May Jun Jul Aug Sep
Oct Nov Dec
23
In general, outdoor winter use is less
consumptive than in summer.
24
General Components of Water Use
Winter baseline (avg of winter months)
Gross Pumping from Data
Typical pattern for purveyors with no
ag-irrigation component
Ag Irr
Landscape Irr
Pumping Rate
Indoor Use
Jan Feb Mar Apr May Jun Jul Aug Sep
Oct Nov Dec
25
The Good News.
26
5 percent reduction in current pumping Gain at
Spokane gage
An approximate gain of 5 13 CFS is predicted.
27
The Bad news..
28
15 increase in pumping Loss at Spokane gage
An approximate loss of 15 40 CFS is predicted.
29
less water for industry and jobs
30
waste management..
31
Power Generation
32
for our quality of life
33
our clean, potable, sole source of drinking water
34
What next? For the project team..

• Continue our partnership- enhance and preserve
  the model
• Partner with governments and others
• Build a water management strategy that is
  acceptable to Idaho and Washington
• Avoids need for federal intervention in
  developing a solution
• Politically, economically and socially acceptable
• Develop tools and techniques that can be used in
  other basins
• Conduct true Regional water planning and outreach

35
For the citizens in our region

• Get involved in water planningmake your feelings
  known
• Use more? Pay more.
• Conserveor maybe just dont waste
• Fix a leak
• Irrigate at night
• Sweep, dont wash your driveway
• Remember, we live in the West

36
For the model Enhancements

• Now Spreadsheet tools
• Now Outreach and meetings with users and major
  stakeholders
• Soon, dependent upon funding Develop
  computer-based tools that address the
  relationship between water systems and population
  systems. Once integrated and made widely
  available in the region- hopefully foster
  understanding among a more diverse group of
  stakeholders.

37
For the Model Upgrades

• Prepare those spreadsheet tools
• Empirically assess the recharge term
• Reassess the Coeur dAlene lake recharge term
• Generate Coeur dAlene lake Water Balance

38

39
(No Transcript)
40
Spokane Valley Rathdrum Prairie Aquifer Study
Questions?
Contact Guy J. Gregory, L.G., L.
Hg. 509-329-3509 ggre461_at_ecy.wa.gov Or visit the
project websites http//www.idwr.state.id.us/hydr
ologic/projects/svrp
41
(No Transcript)