HCI Project PO 1-31-07 - Laserfiche WebLink

Home Browse Search

Colorado River Water Conservation District Hydro - Climate Studies and Predictions Statement of Work The scope of HDR's proposed services focuses on the examining the precipitation and streamflow trends for a number of watersheds in Colorado and relating these variables to HydroClimate Indicies "Cl). This proposed scope will address the relationships of these variables within four basins that have been identified that are identified as having current or near -term pressures in the arena of water supply. These basins are identified as: 1. Arkansas River (above Pueblo Reservoir — Tasks A & B) 2. Dolores -San Juan River Basins (Tasks A & B) 3. Rio Grande River Basin (Tasks A & B) 4. Upper Colorado, Gunnison, and Yampa -White River basins (Task B). All analyses and results described in the Statement of `York will be related to these four basins and sub -basins (if applicable). Tasks — Hydro - Climate Definitions and Relationships HDR proposes two primary inter - related Hydro - Climate tasks to enhance the understanding of and the risk assessment of future water supply in these specific basins. The two tasks have two specific sub -tasks each and are outlined below: / Description of the relationships of hydro - climate indices on the basin- specific precipitation and runoff values and the timing of the runoff values on a seasonal time scale. / Description of the relationships of hydro - climate indices on the basin- specific precipitation and runoff values on a multi- seasonal basis. / Description of the relationships of hydro - climate indices on the basin- specific demand factors that can affect water demand on seasonal time scales. 1 Description of the relationships of hydro - climate indices on the basin - specific demand factors that can affect water demand on multi - seasonal time scales. Task A: Development of the hydro - climate indices (HCI) - basin response relationships on a seasonal basis. / Supply: Relate the amount of basin average precipitation values during the October to March period and the April to September volume runoff into the basins to the following HCI's. These relationships will be calculated for the Dolores -San Juan, Rio Grande and Arkansas basins.: • Multivariate ENSO Index (NIEI) for the periods of Jul /Sep through Oct /Dec three -month averages and five -month averages. • Pacific Decadal Oscillation (PDO) for similar periods as AIEI, • North Atlantic Oscillation (NAO) for similar periods as MEI HDR Page 1