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Integration of Data and Tools <br />CDSS anu! IHA <br />Because there are few (3) gages with sufficient period of record to calculate historical flow <br />parameters using IHA, the possibility of using CDSS baseflow nodes (see Figure 2 for locations) <br />looks promising. To accomplish this we need to: <br />1) Access the quality and applicability of the baseflow data; <br />2) Determine if more baseflow nodes can be added and if there is enough real data to <br />produce believable data (Need to be done soon) look at CDSS output for the tl.,ree <br />gauging stations with long historical records to assess how reasonable this approach is; <br />3) Provide CDSS output that can be input into IHA (use TS tools?) <br />4) Discuss with The Nature Conservvlcy's Sustainable Waters Program and Smythe <br />Scientific Software of Boulder, Colorado the feasibility of using monthly data in IHA by <br />either: <br />a. Reprogramming IIIA; or <br />b. Calculating daily values from monthly data; <br />5) Determine when daily data will become available; and, if necessary, can the time frame <br />be altered to meet our project need:> and what would it cost to do this. <br />The intention is to determine, for all the baseflow nodes, the range of natural variability for the <br />selected flow parameter reflecting snow-melt dominated systems that have the ability to be <br />calculated using CDSS output. The 25`~ and 75~' percentile and mean values (a hydrologist and a <br />statistician will be consulted to determine i:f there are more appropriate cutoff values) will be <br />related to each baseflow node. Real time si:ream gage data and simulated CDSS outpuT which <br />gives us tfl;.e ability to access a larger proporition of stream in the basin will be evaluated using the <br />range of natural variability values. Using the CDSS characterization of wet, dry, and average <br />conditions for every month of every year we will evaluate each node for selected extreme and <br />average cc+nditions. <br />CDSS ar~~! NHD <br />The hydrologic capability of StateMod and. the reach indexing and hydrologic routing <br />capabilities of the NHD m®del are cornplirnentary. From StateMod, streams, gages, and <br />diversions (in some cases the diversion are aggregated) are incorporated in the hydrologic model. <br />The outputs for both the baseflow and simulated flows are lined to a unique id. These nodes are: <br />represented as point features (Figure 2). Some of these point features representing ,gages are <br />incorporated in the NHD geodatabase model. The rest of the nodes will be added to the NHD <br />geodatabase. We will access the feasibility of snapping these features to the flowline (stream). ;In <br />places whE,re there is the possibility of the nodes being incorrectly associated with nearby small <br />tributaries this process will take place manually. The CDSS data files can then be related to the <br />NHD stream layer. This allows us to capitalize on both the relationships and modeling of CDSS <br />as well as the networking capability, relationships of streams to basins and their associated <br />landscape characteristics, graphic capabilities, and analysis functions built into NHS and ArcGIS <br />and Arc Hydro. Alternatively, daily stream flow data and the NHDinGeo data model may be <br />used as an input to the CDSS. The input structure for CDSS needs to be determined to see if this <br />is feasible and reasonable. <br />7 <br />