Klamath Basin Water Distribution Model Workshop
description
Transcript of Klamath Basin Water Distribution Model Workshop
Klamath Basin Water Distribution Model Workshop
OUTLINE
Brief Description of Water Distribution Models
Model SetupsExamples of networks and inputs
Demand Estimates and Checks
Two Simple Modeling Examples
The Klamath Basin
Question and Answers
•What is a water distribution model?
A water accounting system. Routes water within a distribution network (stream, canal, etc.)to demands based on priority and supply.
Brief Description of Water Distribution Models
River
Demand 1,1967 priority
Basin Boundary
Demand 2,1905 priority
Basin Outlet
Demand 3, 1865 priority
Demands #1 and #2 normallywould not compete for water because they are on different tributaries. However, due to theexistence of a downstream demand(#3) with a senior priority date, there is an interaction betweendemands #1 and #2.
Model Setups
• Network Examples and Data Requirements
• Network Examples
•General Network Description
•The Ideal Network
•The Workable Network
•The Common Network
General Network Description
•Links represent tributaries or streams
•Source (inflow) nodes represent flows at tributary confluence
•Physical length of links are unimportant. Monthly time step eliminates need to calculate travel times.
•Relative placement of source nodes, demands and tributary confluence are important.
• Unknown Parameters
Physical
River
Demand 1
Basin Boundary
Schematic
River
Source 1
Source 3
Source 2
Demand 1
Demand 2
Source 1 Source 2 Source 3 Net Demand 1 Net Demand 2 Basin Outflow
Demand 2
Basin Outlet
Basin Outflow
• 3 Types Sources (Inflows) Net Demands Outflows
In aggregatedterms, if any twoparameters areknown the thirdcan be determine.
General Network Description
Tributary 1
Tributary 2
Tributary 3
The Ideal Network
•All demands, inflows and outflows within the basin are measured.
•No estimates required.
River
Flow AccountingPhysical
River Gage
Demand 1
Demand 2
Basin Boundary
Schematic
Source 1
Source 3
Source 2
Demand 1
Demand 2
Source 1+ Source 2+ Source 3- Demand 1- Demand 2 Gage Record
Because of return flows, Sources -Demands Gage Flows
Return flows can be directlycalculated.
Sources - Gage Record= Net Demands
Demands-Net Demands= Return Flows
The Ideal Network
The Workable Network.
•Two out of three parameters are known.
inflows and outflows, orinflows and demands, or
outflows and demands.
• Other parameter can be calculated directly.
Physical
River Gage
Demand 1
Demand 2
Basin Boundary
Schematic
River
Source 1
Source 3
Source 2
Demand 1
Demand 2
Source 1+ Source 2+ Source 3- Net Demand 1 - Net Demand 2 = Gage Record
Calculated Net Demandsdirectly (in aggregate terms)
Flow Accounting
Source Flows- Outflows= Net Demands
The Workable Network
Project Areas 1 and 2are similar to the “workable network”. Net demands are calculated from gage recordsof inflows and outflows from the project.
The Common Network.
• Only one out of three parameters are known. (Usually sub-basin outflow).
• Requires estimation of one of the unknown parameters.
Physical
River Gage
Demand 1
Demand 2
Basin Boundary
Schematic
River
Source 1
Source 3
Source 2
Demand 1
Demand 2
Source 1+ Source 2+ Source 3- Net Demand 1- Net Demand 2 = Gage Record
Flow Accounting
Gage Record+ Net Demands= Source Flows(Zero Demand Flow)
The Common Network
Need to estimate eithersource flows or net demands.Due to data limitations andtime constraints, net demandswere estimated in most areas above Klamath lakeinstead of source flows. Sourceflows can then be calculatedaccording to the formula below.
Physical
River Gage
Demand 1
Demand 2
Basin Boundary
Schematic
River
Source Flow
Net Demands
Flow Accounting
Gage Record+ Net Demands = Source Flow
OR
Zero Demand Flow
The Common Network Aggregated
This estimation of net demandsand consequent calculationof source flows does not allowthe modeling of the individualtributaries and demands.The demands and tributariesare aggregated.
Network Example Summary
•The Ideal Network - No estimates required Gage data used directly to determine demands and flows.
•The Workable Network - Net Demands are directly calculated. Demands may be Aggregated. •The Common Network - Estimates of either source flows or net demands are required. Demands and source flows are aggregated.
Demands
•Estimates: How are net demands estimated?•Checks
Net Demand = (Evapotranspiration - Precipitation - Soil Moisture) x Acreage •Evapotranspiration estimated from Temperature Records using Hargreaves Equation.
•Precipitation taken from Rain Gage Data
•Soil Moisture estimated using Soil Conservation Service Surveys, and Antecedent Precipitation
•Crop Acreage
Example:
Monthly Net Demand = (Evapotranspiration - Precipitation - Soil Moisture) x Acreage
Monthly Net Demand = (7 inches - 0.5 inches - 0.5 inches) * 1000 acres
= 500 ac-ft or 8.1 cfs
Demand Estimates Checks•Diversions
Simulated versus Measured• Canal Data• Depleted Flow Data
• Annual Net Demand EstimatesSimulated versus Measured
•Average•Yearly Trends
•Annual Crop ETSimulated versus “Agrimet” Data
Diversions
•Simulated versus Measured Canal Data
Modoc Diversion Canal:Comparison of simulated monthly average versus miscellaneous daily measurements.
1981 Modoc Diversions
0
10
20
30
40
50
60
70
80
Mar Apr May Jun Jul Aug Sep Oct
(cfs
)
Predicted (Monthly) Actual (Single Measurement)
1980 Modoc Diversions
0
10
20
30
40
50
60
70
80
Mar Apr May Jun Jul Aug Sep Oct
(cfs
)
Predicted (Monthly) Actual (Single Measurement)
1984 Modoc Diversions
01020304050607080
Mar Apr May Jun Jul Aug Sep Oct
(cfs
)
Predicted Monthly Actual Single Measurement
1983 Modoc Diversions
01020304050607080
Mar Apr May Jun Jul Aug Sep Oct
(cfs
)
Predicted Monthly Actual Single Measurement
1986 Modoc Diversions
01020304050607080
Mar Apr May Jun Jul Aug Sep Oct
(cfs
)
Predicted Monthly Actual Single Measurement
1985 Modoc Diversions
01020304050607080
Mar Apr May Jun Jul Aug Sep Oct
(cfs
)
Predicted Monthly Actual Single Measurement
1987 Modoc Diversions
01020304050607080
Mar Apr May Jun Jul Aug Sep Oct
(cfs
)
Predicted Monthly Actual Single Measurement
Average for Available Records
0
10
20
30
40
50
60
Mar Apr May Jun Jul Aug Sep Oct
Div
ersi
on (
cfs)
Modoc Simulated
Diversions
•Simulated versus Measured Depleted Flows
Wood River 91-93:Inflows from tributaries calculated
from miscellaneous records.
Demands estimated using previously described method.
Outflows taken from BOR gage data.
Physical
RiverGage
Demand 1
Demand 2
Basin Boundary
Schematic
Source 1
Source 3
Source 2
Demand 1
Demand 2
Source 1+ Source 2+ Source 3- Net Demand 1- Net Demand 2 = Outflows
Flow Accounting
Compare SimulatedOutflow to Gage datato check estimates
Wood River
0100200300400500600700
cfs
Simulated Flow Zero Demand Flow
Measured Flow
Wood River
0100200300400500600700
cfs
Simulated Flow Zero Demand Flow Measured Flow
Wood River
0
100
200
300
400
500
600
700
10 19
93
11 19
93
12 19
93
1 199
3
2 199
3
3 199
3
4 199
3
5 199
3
6 199
3
7 199
3
8 199
3
9 199
3
10 19
94
cfs
Simulated Flow Zero Demand Flow Measured Flow
Average Measured vs. Simulated Flows of Wood R (4/1991-12/1993)
0
50
100
150
200
250
300
350
400
450
10 11 12 1 2 3 4 5 6 7 8 9
Month
cfs
Simulated Flows Measured Flows
Diversion Check
Simulated diversions appear to be reasonable when compared to measured canal and
depletedflow data.
Annual Net Demand Estimates
Simulated average annual demand above Klamath Lakeversus measured average annual demand in the Project.
• Climate is similar.• Same basin. • Demand is normalized by acreage (ac-ft/ac).
Annual Average Consumptive Demand (ac-ft/ac)
1.52
1.84
0
0.5
1
1.5
2
2.5
3
(ac-
ft/a
c)
Estimated Above Klamath Lake Historical Net Demand In Project
Annual Consumptive Demand (ac-ft/ac)
0
1
2
319
74
1976
1978
1980
1982
1984
1986
1988
1990
1992
1994
1996
(ac-
ft/a
c)
Estimated Net Demand above Klamath Lake Historical Project Demand
Annual Net Demand Estimates Check
• Estimated annual demands above Klamath Lake appear reasonable when compared to measured data available elsewhere in the basin.
• Yearly simulated variations in annual demands generally follow measured data.
Annual Crop ET
• Simulated annual crop ET versus “Agrimet” data in Lakeview.
Simulated Net ET above Klamath Lake vs ET from LakeView Agrimet Station
0.0
5.0
10.0
15.0
20.0
25.0
30.0
1993 1994 1995 1996 1997
Net
ET
(in
)
Simulated LakeView
Model Examples
Integrating Instream Demands
• Single Tributary System• Two Tributary System
Actual
River
Demand 1
Demand 2
Basin Boundary
Schematic
River
Zero DemandFlows
Demand A
Flow Accounting
ZDF-Instream Demands= Flows Available for Irrigation Demands
InstreamDemand
InstreamDemands
Demand A,1864
InstreamDemand C
ZDF Tributary A
ZDF Tributary B
InstreamDemand D
Demand B,1905
Instream demand D has a call on upstream demands. However, the shortages appear in Demand A instead of Demand B even through Demand A has a senior priority date. The reason is that instream demand C is effectively causing the shortages to Demand A, which consequently increases flows to instream demand D. Thus demand B is not called to reduce its use.
Counterintuitive DemandInteraction.
Klamath Basin Setup
Spencer Creek
Lake Ewauna
Project Area A2
Other Tributaries Seeps and Springs
Wood River and Tributaries
Accretions Middle Sprague
ZDF Sycan
Accretions Middle Williamson
ZDF Lower Williamson
Klamath Straits Drain
ZDF Upper Williamson
LEGEND
Channels Source Nodes Consumptive Uses Junctions Marshes/Lakes
GAUGE OVERLAP PERIOD (73-97)
Project Area A1
ZDFSprague
LRDC
Ewauna Accretions