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丧失，土壤粘聚力的降低，土壤的排水性增强，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高峰流量的大小和时间。水质也受到火灾的影响，常常导致营养物质和悬浮泥沙的增加。这一快速建议的目标是收集灾难性野火后原始山区水库系统内水文地球化学行为的即时和必要的现场观测。这项拟议的工作将解决我们在亚高山、以雪为主的火灾后系统中水文流量和水质耦合方面的一个显著空白，特别是关于灾难性野火后的痕量金属行为。环大火烧毁了255,858英亩土地，是加州历史上第三大火灾？S，也是内华达山脉最大的火灾之一。火灾后的过程威胁到旧金山市以及其他29个批发买家的供水。Hetch Hetchy水库系统(总共三个湖泊)的供水没有经过过滤，因此特别容易受到环大火造成的浑浊和泥沙负荷增加的影响。收集的数据最终将被用于开发模型和预测工具，以量化对Hetch Hetchy和其他区域湖泊的水量、泥沙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.