WEAP--A Demand-, Priority-, and Preference-Driven Water Planning Model: Part 1, Model Characteristics
Abstract: The Water Evaluation and Planning Version 21 (WEAP21) Integrated Water ResourceManagement (IWRM) model seamlessly integrates water supplies generated through watershed-scalehydrologic processes with a water management model driven by waterdemands and environmentalrequirements and is governed by the natural watershed and physicalnetwork of reservoirs, canals, anddiversions. This version (WEAP21) extends the previous WEAP model byintroducing the concept ofdemand priorities and supply preferences, which are used in a linearprogramming heuristic to solve thewater allocation problem as an alternative to multi-criteria weightingor rule-based logic approaches.WEAP21 introduces a transparent set of model objects and procedures thatcan be used to analyze a fullrange of issues faced by water planners through a scenario-basedapproach. These issues includeclimate variability and change, watershed condition, anticipateddemands, ecosystem needs, the regulatoryenvironment, operational objectives, and available infrastructure.
WEAP--A Demand-, Priority-, and Preference-Driven Water Planning Model: Part 2, Aiding Freshwater Ecosystem Service Evaluation
Abstract: Potential conflicts arising from competing demands of complexwater resource systemsrequire a holistic approach to address the tradeoff landscape inherentin freshwater ecosystem serviceevaluation. The Water Evaluation and Planning model version 21 (WEAP21)is a comprehensive integratedwater resource management (IWRM) model that can aid in the evaluation ofecosystem servicesby integrating natural watershed processes with socio-economic elementsthat include the infrastructureand institutions that govern the allocation of available freshwatersupplies. The bio-physical andsocioeconomic components of Battle Creek and Cow Creek, two tributariesof the Sacramento River ofNorthern California, USA, were used to illustrate how a new hydrologicsub-module in WEAP21 can beused in conjunction with an imbedded water allocation algorithm tosimulate the hydrologic response of thewatersheds and aid in evaluating freshwater ecosystem service tradeoffsunder alternative scenarios.