CAREER: Balancing Local and Systemic Resilience in the Western Water Network

这笔学院早期职业发展(CARAPE)赠款将为西部区域水系统的一大部分提供模型，以帮助促进在地方和区域两级规划有弹性的水供应和使用。水库、渡槽和水泵系统的建设改变了美国西部的水文景观。这些工程壮举通过在空间上(通过跨流域调运和分配基础设施)和在时间上(通过在雨季储存水以供以后使用)来转移水，从而促进了增长。因此，曾经分开的河流流域现在通过调水和共享需求中心联网，在这里被称为西部水网。区域供水网络的建立产生了效益，因为水可以跨流域运输以满足需求，水用户可以通过一系列供水来减轻干旱影响。然而，这种连接也带来了新的风险。正如金融系统中的联系可以降低局部冲击的风险，同时增加系统不稳定的风险一样，相互连接的供水系统在局部风险和系统性风险之间进行了权衡。随着气候变化、需求变化以及未来几年运营规则的重新谈判，这些权衡已经做好了准备。该项目将使用一套模型来评估在最近和当前规则结构下的地方(如市或州一级)和系统(如全流域)复原力之间的权衡，并探索修改以减少在看似合理的未来条件下的失败风险。对这些权衡的新认识将允许在重新设计运营规则和基础设施时有意选择收益和风险。由于相互关联的河流流域并不是美国西部独有的，研究西部水网的经验教训可能适用于全球。该项目解决了在了解联网水系统的本地和系统复原力之间的权衡以及基础设施和机构设计的作用方面的差距。关于这些权衡的新知识现在特别重要，因为供水系统高度优化，可以容忍观察到的历史变化，但社会和气候变化正在推动全球许多供水系统超越这些历史条件。由于这种强大的系统往往比它们以前经历过的脆弱性范围更脆弱，我们需要现在为我们的基础设施和机构系统做好准备，以应对预期的变化。具体地说，这个项目将：1)开发区域径流统计模型，并说明在历史和预测条件下对评估区域水系统至关重要的空间和时间模式；2)建立和测试一个测试案例西部水网模型，将水系统建模与一个能够模拟日常运行和适应性变化的基于主体的模型结合起来；3)评估目前在古历史和预测径流条件下运行的该系统；以及4)评估当前规则结构和当前规则结构下当地和系统复原力之间的权衡，并探讨修改以减少未来合理条件下的脆弱性空间。为了实施这项工作，团队将与利益相关者合作，从他们对系统的默许知识中学习并分享结果。认识到下一代工程师面临的基础设施挑战的多面性，该项目还将开发教育模块和技术，以指导学生进行适用于课堂内外的综合。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This Faculty Early Career Development (CAREER) grant will model a large component of the western regional water system to help facilitate planning for resilient water supply and usage at both local and regional levels. The construction of reservoirs, aqueducts, and pump systems has transformed the hydrological landscape of the American west. These feats of engineering have facilitated growth by moving water in space (via interbasin transfers and distribution infrastructure) and in time (by storing water during wet periods for later use). Consequentially, once separate river basins are now networked via water transfers and shared demand centers, here termed the Western Water Network. The creation of a regional water supply network generated benefits as water can be moved across basins to meet demands and water users can mitigate drought impacts with a portfolio of supplies. However, this connectivity also introduces new risks. Just as links in financial systems can reduce the risks of local shocks while raising the risk the system instability, interconnected water supply systems have tradeoffs between local and systemic risks. These tradeoffs are primed to shift as climatic change, demand shifts, and a renegotiation of operating rules play out in the coming years. This project will use a set of models to assess the tradeoffs between local (e.g. municipal or state level) and systemic (e.g. basin wide) resilience under recent and current rule structures and explore modifications to reduce the risk of failure under plausible future conditions. New knowledge of these tradeoffs will allow the deliberate choice of benefits and risks when re-designing operating rules and infrastructure. As interconnected river basins are not unique to the America West, lessons from study of the Western Water Network may be applicable globally. This project addresses a gap in understanding the tradeoffs between local and system resilience in networked water systems, and the role of infrastructure and institutional design. New knowledge of these tradeoffs is particularly relevant now as water supply systems are highly optimized to tolerate observed historic variability but both social and climatic changes are pushing many water supply systems globally beyond these historic conditions. As such robust systems are often fragile beyond their range of previously experienced vulnerability, we need to prepare our infrastructure and institutional systems now for projected changes. Specifically, this project will: 1) develop statistical models of regional streamflow that account for both the spatial and temporal patterns critical to evaluating regional water systems under historic and projected conditions; 2) build and test a model of the test case Western Water Network that merges water systems modeling with an agent-based model capable of simulating routine operations and adaptive changes; 3) evaluate the system as currently operated under paleo-historic and projected streamflow conditions; and 4) assess the tradeoffs between local and systemic resilience under recent and current rule structures and explore modifications to reduce the fragility space under plausible future conditions. To implement this work, the team will collaborate with stakeholders to both learn from their tacit knowledge of the system and share results. In recognition of the multifaceted nature of infrastructure challenges facing the next generation on engineers, this project will also develop educational modules and techniques for guiding students through synthesis that are applicable within and outside the classroom.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.