Collaborative Research: RAPID Assessment of 2013 Flood Sedimentation, Button Rock Reservoir, North St. Vrain Watershed, CO

合作研究：2013 年洪水沉积快速评估，科罗拉多州北圣弗赖恩流域 Button Rock 水库

• 批准号: 1410663
• 负责人: Brandon McElroy
• 金额: $ 0.84万
• 依托单位: University of Wyoming
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-12-15 至 2014-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1410663&HistoricalAwards=false
• 关键词: Collaborative; Research; RAPID; Assessment; 2013

This collaborative RAPID project will assess flood sedimentation in Button Rock Reservoir, North St. Vrain watershed in north-central Colorado following the September 2013 extreme event. In addition, it will fill knowledge gaps about event-based sedimentation from fires and floods, and expand knowledge to annual and decadal scales using a record of sediment accumulation since construction of the reservoir in 1950. The sedimentary record will inform on trends in basin-averaged erosion rates and sedimentation, as well as on trends in carbon storage in natural or artificial lakes, and on rates of carbon export from North St. Vrain Creek under flow scenarios from single, large events to flows over the past six decades. Button Rock Reservoir provides a unique setting to assess the effects of a very high magnitude, infrequent flood in the Front Range because (1) no intentional flushing events have been conducted by the reservoir operators since construction of the reservoir, (2) the reservoir stratigraphy chronicles uninterrupted delta deposition, and (3) this is the only on-channel reservoir with unimpeded, natural sediment flux from the Continental Divide to the mountain front in a basin with no significant historic timber harvests, flow regulation, or land use impacts. The team will collect four cores within the delta deposit during the December 2013 to March 2014 timeframe. A ground-penetrating radar survey will be completed of the exposed delta and subaqueous portions of the reservoir. Together with information from pre-dam topographic maps, information from these cores and the GPR survey will constrain the volume and spatial distribution of sediment deposition. Samples from the delta cores will be collected for radiocarbon analysis to constrain sediment accumulation and provide insight into landscape denudation through basin-averaged erosion rates. The carbon flux within the catchment will be determined from organic carbon content in delta sediments. Discharge and precipitation records will be compared with the core information to analyze trends in sediment flux into the reservoir in response to event-based and seasonal drivers.This project will collect a unique uniterrupted and undisturbed record of the impact of floods and fires on erosion in Colorado's Front Range over the past six decades. It will inform understanding of how the landscape responds to such major events and the role of these events in moving Carbon among storage points in the landscape. A near-term outcome of the work will be a refined estimate of the amount of material moved by the September 2013 weather event--an event that has necessitated the City of Longmont to remove the associated pulse of sediment from the Button Creek Reservoir in order to regain reservoir capacity. The project presents training experiences for graduate and undergraduate students, forges a new collaboration between colleagues at two universities, and will share information with entities that manage water and sediment flows along the Front Range.

该合作RAPID项目将评估2013年9月极端事件后科罗拉多中北部北圣弗兰流域巴顿岩水库的洪水沉积。此外，它将填补关于火灾和洪水造成的事件沉积的知识空白，并利用1950年建造水库以来的沉积物积累记录，将知识扩展到年度和十年尺度。沉积记录将提供有关流域平均侵蚀速率和沉积的趋势，以及天然或人工湖泊中碳储存的趋势，以及过去六十年来从单一大型事件到流量的流量情景下北圣弗兰溪的碳出口率。 巴顿岩水库提供了一个独特的环境，以评估非常高的量级，罕见的洪水在前线的影响，因为（1）没有故意冲洗事件已由水库运营商进行自水库建设，（2）水库地层编年史不间断三角洲沉积，（3）这是唯一的渠道水库，从大陆分水岭到盆地山前的自然沉积物通量，没有重大的历史木材采伐、流量调节或土地利用影响。 该团队将在2013年12月至2014年3月的时间范围内收集三角洲存款内的四个核心。 将完成对水库暴露的三角洲和水下部分的探地雷达勘测。这些岩芯和地质雷达测量的信息与坝前地形图的信息一起，将限制沉积物沉积的体积和空间分布。将收集三角洲岩心样本进行放射性碳分析，以限制沉积物积累，并通过盆地平均侵蚀速率提供景观剥蚀的见解。 流域内的碳通量将由三角洲沉积物中的有机碳含量确定。 排放和降水记录将与核心信息进行比较，以分析沉积物通量进入水库的趋势，以响应基于事件和季节的drivers.This项目将收集一个独特的uninterrupted和未受干扰的记录洪水和火灾的影响侵蚀在科罗拉多的前山脉在过去的六十年。 它将为了解景观如何响应这些重大事件以及这些事件在景观中的存储点之间移动碳的作用提供信息。 这项工作的近期成果将是对2013年9月天气事件移动的材料数量的精确估计-这一事件迫使朗蒙特市从巴顿溪水库中清除相关的沉积物脉冲，以恢复水库容量。 该项目为研究生和本科生提供培训经验，在两所大学的同事之间建立新的合作关系，并将与管理前山脉沿着水和沉积物流动的实体分享信息。