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<br />addition, considerations of compact compliance, the Statewide Conprehensive Wildlife Conservation Strategy and the
<br />CWCB instream flow program (including water-short reaches) will inform basin priority setting,
<br />
<br />3.3. Quantification
<br />3.3.1 "Triage" - Where do we need quantification?
<br />The NCNA Workgroup does not expect that quantification will be necessary for all values In all reaches To assist In
<br />determining where quantification is truly necessary, the workgroup will develop criteria to help evaluate the need for
<br />quantification in priority reaches, The "triage" process will begin with the prioritized reaches and areas, Roundtables, with
<br />the assistance of the NCNA Workgroup (possibly through development of a set of criteria for thiS purpose) will consider the
<br />condition of the reach or area as well as its existing status or land use protection, Based on this evaluation, the roundtable
<br />will decide if it would be appropriate to perform a quantification
<br />
<br />Here are two examples of how status and condition may affect the decision regarding whether a quantification is necessary:
<br />
<br />.
<br />
<br />An area or reach may not need quantification because its flows and habitat are already protected as a result of land use
<br />decisions (e,g" the area or reach lies within a wilderness areas without existing conditional water rights) and/or has an
<br />appropriation for a CWCB instream flow water rights Such an area or reach would likely be well functioning and not at
<br />any present or likely future risk,
<br />
<br />.
<br />
<br />An area or reach may not need a quantification because there are alternative mechanisms available to protect its
<br />environmental or recreational values For example, there IS a senior downstream calling right and an Instream flow
<br />water right. Or, in the case of, a tributary that does not reach the mainstem because there is a ditch diversion within a
<br />mile of the mainstem confluence, it may be easier and more cost-effective to move the headgate to the mainstem with a
<br />change In point of diversion, thereby re-connecting the tributary, as well as apply for a new state instream flow water
<br />right, rather than perform a quantification which could then be used to acquire a water right for instream ftow protection,
<br />
<br />In addition, there may be upcoming proposed water projects or agency actions (e,g" listing under the Endangered Species
<br />Act) that warrant gathering quantification data on a particular reach or area more quickly
<br />
<br />3.3.2 Templates {Coarse Characterization}
<br />The COM Technical Team, with the assistance of outside expertise such as The Nature Conservancy and Colorado State
<br />University, Will develop approximately ten templates for Colorado stream and river types, based on gross differences in
<br />hydrology and function, For example, there would be templates for: high mountain headwaters, ephemeral desert washes,
<br />large, or mainstem rivers, plains groundwater fed streams and fens, The template would provide a model hydrograph as well
<br />as specify which components of the hydrograph are important for specific ecological and recreational attributes The model
<br />hydrograph will be similar to a synthetic unit hydrograph and will prescribe the properties of the flow regime required to
<br />maintain ecological and recreational function of a system, Note that, for some, but not all recreational attributes, maintaining
<br />ecological function Will also support the recreational attribute For example, a high quality birding area may need high quality
<br />riparian vegetation, so a model hydrograph that protects the reach associated with the birding areas riparian zone is likely
<br />also to protect the birding attribute,
<br />
<br />3.3.3 Site-Specific Quantification {Fine Characterization}
<br />Based on the "triage" or where priority reaches warrant site-specific quantification, the COM Technical Team and outside
<br />expertise will use the appropriate general template from the coarse characterization and apply it to the specific river reach
<br />using existing data regarding flow (e,g" from existing gages, RiverWatch observations, the relevant OSS, or other sources)
<br />and function (e,g" from the attributes), At a minimum, there should be sufficient data to develop site-specific quantifications
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