Part 1: Framework Development and Selection of Parameters To lay a foundation for the appraisal process the Institute reviewed existing water resources assessment frameworks, reports, and other information from Louisiana and other states with regard to their approach, scope, technical content, scientific basis, geospatial/hydrologic scale of analysis, methods of future projection, and other key components. Widely shared features of many of the plans include short term (seasonal and annual) and long term (decadal) planning, planning based on hydrologic units, planning for surface water and groundwater, and developing water allocation strategies only after statewide water resource planning is underway. Some novel features identified in individual plans include critical areas planning, conjunctive management of both surface and ground water, linking water quality and quantity, and planning for conservation and efficiency particularly in states with experienced water shortages. Guidance for linking energy & water supply was gained from a review of California's Water – Energy Relationship (California Energy Commission, 2005). Novel aspects of water planning in Louisiana include the continental-scale Mississippi River, coastal demand for fresh water, and integration of water planning with the Coastal Master Plan.
FRAMEWORK DESCRIPTION The assessment framework was developed to provide an appraisal of current and expected future water supply and use and to develop a planning instrument that can better inform management decisions and minimize the potential impact of future growth on overall water supply costs, including for energy use. The framework includes a conceptual water budget that can be used to estimate the total water supply and demand in hydrologic units across the state, a water balance equation that mathematically relates the inputs and outputs of the hydrologic system in these areas, and a method for determining the potential impacts of future demand and supply constraints. This framework can be used to assess each of the state’s hydrologic units with regard to water supply sustainability for relevant existing and potential uses, including energy conservation. The framework has been constructed to provide uniformity of analysis across hydrologic units using existing data sources. Many elements of the assessment framework can be measured directly using existing data sources or estimated using established techniques. To minimize the impacts of known or expected gaps in information and data, those elements that could not be measured directly were calculated using the water balance equation. For purposes of constructing the conceptual water budget, water units were categorized as surface water (streams, lakes, and reservoirs), surface alluvial/unconfined groundwater, or confined/deep groundwater storage units. Inputs and outputs for each of these water unit types were identified, and linkages between water units were established in the framework. Water quality, with respect to how it may affect the quantity and availability of a water resource, can also be considered within the framework. A diagram of the conceptual water budget can be seen in Figure 1. The framework supports calculation of a water budget to appraise sustainability by quantifying the inflows, outflows, and unallocated water for the hydrologic units of interest. The derived water budget maintains that for any given period, the change in the volume of unallocated water within each unit of
Water Resources Assessment for Sustainability and Energy Management
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