Dynamic Management of Water Storage in Watersheds for Reducing the Magnitude of Floods

在美国，洪水造成的生命损失、财产和农作物损失比任何其他自然灾害都要多。防洪的结构性措施，如堤防，仅限于流域的一小部分，在减少洪水的能力和稳健性方面是有限的。社区需要的防洪解决方案要能在流域提供更多的蓄水量，对降水和土地利用变化的趋势具有灵活性，并且在环境上是可持续的。本项目将探索一种基于湿地蓄水动态管理的防洪方法。该策略将使湿地能够在降雨事件发生前数小时或数天适应性地释放水，从而最大限度地提高储存容量，同时保持或增加湿地的生态功能。该项目的具体目标是：(1)确定操纵水期（水深随时间变化）对休斯敦哈里斯县典型湿地群落的生态影响；(2)建立一套模块化的主动控制系统，用于湿地蓄水的动态管理；(3)研究湿地面积（面积和可用蓄水）与流域面积的关系，以及蓄水管理程度如何影响流域尺度上的洪水强度。为尽量减少对生态的影响，有关降低水位的限制将列入管理策略。目标1的任务包括进行一项中尺度野外实验，以确定哈里斯县典型湿地群落的大范围水期操纵的生态后果。这将评估期望的水文操作（降雨事件前的减少）和管理错误（降雨事件未能如预测的那样实现）的生态影响。目标2的任务包括对一套用于蓄水管理的湿地网络远程操作的模块化主动控制器进行实地测试。目标3的任务包括(a)进行成本效益分析，以评估减少洪水规模的建议方法的可行性；(b)建立一个决策支持系统（DSS），用于评估动态蓄水管理对流域洪水规模的影响。主要的教育目标是增加未被充分代表的学生在本科工程项目中的参与。为此，我们将在现有的拓展项目中为科学教学创建以防洪为重点的实践活动，主要针对代表性不足的中学生。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Floods are resulting in more loss of lives and damage to property and crops than any other natural disaster in the United States. Structural measures for flood control, such as levees, are constrained to only a small part of a watershed, and are limited in their capacity and robustness to reduce floods. Communities need flood control solutions that provide more storage in the watershed, are flexible to trends in precipitation and land use changes, and are environmentally sustainable. This project will explore an approach for flood control that is based on the dynamic management of water storage in wetlands across the landscape. The strategy will enable adaptive release of water from wetlands hours or days ahead of rainfall events, thereby maximizing storage capacity while at the same time maintaining or increasing wetland ecological function. The specific objectives of the project are to: (1) determine the ecological consequences of manipulating the hydroperiod (water depth changes over time) for wetland communities typical of Harris County, Houston; (2) create a set of modular active controls for dynamic management of storage in wetlands, and (3) examine how the size of wetlands (area and usable storage) in relation to the watershed area, and the degree of water storage management, impact the magnitude of floods at the watershed-scale. To minimize ecological impacts, constraints on water level reductions will be included in the management strategy. Tasks for Objective 1 include conducting a mesocosm field experiment that will determine the ecological consequences of a wide range of hydroperiod manipulations for wetland communities typical of Harris County. This will both assess the ecological impacts of desired hydrological manipulations (drawdown before rainfall events) and also of management mistakes (rainfall events that fail to materialize as predicted). Tasks for Objective 2 include field tests of a set of modular active controls for the remote operation of a network of wetlands for water storage management. Tasks for Objective 3 include (a) performing a cost-benefit analysis to evaluate the feasibility of the proposed approach for reducing the magnitude of floods; and (b) creating a Decision Support System (DSS) for evaluating the impact of dynamic water storage management on the magnitude of floods at the watershed-scale. The main educational goal is to increase participation of underrepresented students in undergraduate engineering programs. To this end, the project we will create hands-on activities focusing on flood control for science instruction in an existing outreach program, targeted primarily to underrepresented middle-school students.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.