CRDSS_Task1_15-28_ProofOfConcept_BaseFlowsAtCoreStationsNodes

• Title: CRDSS Task 1.15-28 - Water Rights Planning Model - Proof of Concept for the Development of Base Flows at Core Stations and at Intermediate Nodes
• Description: This memorandum describes the procedure to be used in developing base stream flows at selected U.S. Geological Survey ‎(USGS)‎ ‎(core)‎ gaging stations.
• Decision Support - Doc Type: Task Memorandum
• Date: 1/9/1995
• DSS Category: Surface Water
• DSS: Colorado River
• Basin: Colorado Mainstem
• Contract/PO #: C153658, C153727, C153752
• Grant Type: Non-Reimbursable
• Bill Number: SB92-87, HB93-1273, SB94-029, HB95-1155, SB96-153, HB97-008
• Prepared By: Riverside Technology inc.

Pull Historical Time Series from CRDSS Database
The first step is to hit the CRDSS database using crdssgr to obtain historic time series information in
STATEMOD format for Taylor Park reservoir and the two USGS stream gaging stations. The
following command line arguments are run to pull time series data from the database. A hard copy
of the time series information is contained in Exhibit B. The command line arguments required to
obtain net reservoir evaporation at Taylor Park reservoir are detailed in the proof of concept
memorandum for the netresev data management interface (DMI).
crdssgr 15119..RSTO.MONTH.1 -statemod -o EOMCON.ex1
crdssgr 09110000..QME.DAY.109109000..QME.DAY.1 -units AF/D -statemod -o VIRHIS.ex1
crdssgr 5018.CRDSSGeoloc.QME.DAY.1 -units AF/D -statemod -o DIVDAT.ex1
netresev EVADAT.ex1 -ft P=8184 E=8064 -w.5 E=130 -w.5
Develop Base Flow Estimates at Core Stations
In order to develop base flows, the Taylor River above Almont is represented as a stream node
network based on the location of the two gages, the reservoir, and the diversion. Exhibit B contains
the input files developed for the representation of the basin. Base flows are generated by executing
STATEMOD?s base flow module. Results from this run ( base.out ) are shown in Exhibit C.
Redistribute Base Flow to Intermediate Nodes
Once the base flows have been determined for the core stations, the total reach gains between core
stations will be determined by computing the difference between the estimates of base flow at the
stations. The total reach gain will then be redistributed to intervening nodes using a flow proration
factor. The flow proration factor for an intervening node will be multiplied by the total reach gain to
determine the intermediate reach gain above the node.
The redistribution of base flows to intermediate nodes is accomplished by executing STATEMOD?s
base flow module. Results from this run are shown in Exhibit C. Flow proration factors are
determined external to STATEMOD and are supplied to the model in the file node.cor, which is
shown in Exhibit B.
The flow proration factor (P) for intervening nodes is determined by dividing the local contributing
area above a node by the total local contributing area between core stations. Equation 1 shows the
general calculations required to develop a flow proration factor.
DA
=
i
P
Equation 1
DA
lt
D A
where is the intervening drainage area between the upper core station and the intermediate node
i
DA
of interest, is the local drainage area between successive core stations.
lt
The flow proration factor for inflow points 1 and 2 (Nodes 10 and 30) can be determined using the
drainage area information given in Table 1.
2
A275 03.20.95 1.15-28 Ritsch