NSF RAPID: The 2013 Rim Fire: Survey of Potential Water Quality Impacts on the Hetch Hetchy Reservoir System

野火对流域的物理和化学过程有直接/直接的影响，包括植被和土壤有机质的急剧损失，土壤凝聚力降低，土壤疏水性增强，灰层沉积，入渗减少和径流增加。这些变化极大地影响了火灾后峰值流量的大小和时间。水质也受到火灾的影响，经常导致营养物质和悬浮沉积物的增加。这项RAPID计划的目标是在灾难性野火发生后，收集原始山区水库系统中水文地球化学行为的即时和必要的现场观测数据。这项工作将解决我们对亚高山、积雪主导的火灾后系统中水文通量和水质耦合的认识上的重大空白，特别是在灾难性野火后的痕量金属行为方面。“环火”已经烧毁了255,858英亩的土地，是加州第三大火灾。它是美国历史上最大的火山之一，位于内华达山脉。火灾后的处理过程威胁到旧金山市以及其他29个批发买家的供水。来自Hetch Hetchy水库系统（总共三个湖泊）的供水未经过滤，因此特别容易受到由于边缘火灾而增加的浊度和沉积物负荷的影响。收集到的数据最终将用于开发模型和预测工具，以量化对进入Hetch Hetchy和其他区域湖泊的水量、沉积物通量和污染物负荷的短期和长期影响，这些湖泊几乎是SF供水系统的单一输入。

Wildfires have a direct/immediate impact on physical and chemical processes in watersheds including acute loss of vegetation and soil organic matter, decreased soil cohesion, enhanced soil water repellency, ash layer deposition, decreased infiltration and increased runoff. These changes greatly impact the magnitude and timing of post-fire peak flows. Water quality is also impacted by fires often resulting in increases in nutrients and suspended sediment. The goal of this RAPID proposal is to collect immediate and essential field observations of hydro-geochemical behavior within pristine mountain reservoir systems following a catastrophic wildfire. The proposed work will address a significant gap in our knowledge of the coupling of hydrologic flux and water quality in sub-alpine, snow-dominated post-fire systems, especially with regards to trace metal behavior after a catastrophic wildfire.The Rim Fire, which has burned 255,858 acres, is the third largest fire in California?s history and is one of the largest in the Sierra Nevada. Post-fire processes threaten water supplies to the city of San Francisco as well as 29 other wholesale buyers. Water supply from the Hetch Hetchy reservoir system (three lakes in total) is unfiltered and therefore especially vulnerable to increased turbidity and sediment loads as a consequence of the Rim Fire. Collected data will ultimately be used to develop models and predictive tools to quantify short and long-term impacts on water quantity, sediment flux and contaminant loads into Hetch Hetchy and other regional lakes which encompass a nearly singular input to the SF water supply system.