RAPID: The Impact of Rural and Urban Flooding on Water and Soil Quality in the Red River Valley of the North

与地下土壤水相比，农业和城市地区的地表径流含有更高浓度的无机和有机化学物质。由于2008年秋季的天气状况，2008年12月创纪录的降雪量，以及最近的暴风雪事件(2009年3月)，美国国家气象局预测，明尼苏达州法戈、ND和穆尔黑德等城市的北方红河(RR)水位可能达到河底以上12.5米，超过1897年4月7日创下的目前12.2米的纪录。法戈的主要洪水位为9.1米。因此，这一快速建议的目的是量化农业和城市径流对位于北部红河沿岸的北达科他州(法戈市)和明尼苏达州(穆尔黑德市)这两个主要城市地区上下游的水和土壤质量的影响。之所以迫切需要这笔赠款，是因为RR水位刚刚开始增加深度，预计最大洪水位将在2009年3月下旬达到。这一事件被归类为500年的洪水，预测的过程线显示洪水只有20到30天。这项研究将检验两个假设：1)洪水-水质将受到洪水通过大型城市环境的影响；2)洪水后沉积在河岸和城市景观上的沉积物的化学浓度将高于底层土壤。假设1将通过采集法戈-穆尔黑德主要人口中心上游和下游的水样进行评估，并将对水样进行17？雌二醇(E2)和雌酮(E1)、总汞、总汽油碳氢化合物、总柴油碳氢化合物、硝酸盐、铵、磷酸盐、pH、电导率、硫酸盐、氯化物和总悬浮固体的分析。假设2将通过对三个被洪水淹没超过14天的低洼地区进行抽样来评估，这些地区将包括一个自然河岸区、一个社区花园或公共公园，以及一个城市草坪。沉积的大量沉积物将被测定，沉积物和下层土壤的雌二醇(E_2)和雌酮(E_1)、总汞、总汽油碳氢化合物、总柴油碳氢化合物、硝酸盐、铵、磷酸盐、pH、电导率、硫酸盐和氯离子将被量化。拟议研究的智力价值包括扩展关于来自和穿过农村景观和城市中心的洪水如何影响水和沉积物质量的知识。这项工作将增加我们对洪水水质在通过大平原北部城市中心时受到的影响，以及沉积的沉积物如何影响土壤质量的理解。法戈-穆尔黑德的许多低洼地区被用作公园、社区花园和草坪，提供洪水后沉积物质量的信息对科学和公共社区很重要。洪水是自然发生的，但洪水的来源会影响低洼地区的水质和土壤质量。拟议研究的更广泛影响包括更好地了解大洪水对大型城市社区在水质和沉积物质量方面的影响。培训一名研究生并通过演讲和发表文章向公众和科学界传播这项研究的结果将是这项研究的主要重点。地方和州政府官员将对这项工作的结果特别感兴趣。

Surface flow off agricultural and urban areas contains elevated concentrations of inorganic and organic chemicals compared to subsurface soil waters. Due to weather conditions during the fall of 2008, record snowfall in December of 2008, and a recent blizzard event (March 2009), the National Weather Service is predicting that the water level of the Red River of the North (RR) in the cities of Fargo, ND and Moorhead, MN may reach 12.5 m above the river bottom, which would surpass the current record of 12.2 m set on 7 April 1897. The major flood level for Fargo is 9.1 m. Therefore, the purpose of this RAPID proposal is to quantify the effects of agricultural and urban runoff on water and soil quality upstream and downstream of a major urban area of North Dakota (Cities of Fargo) and Minnesota (City of Moorhead), which are located along the banks of the Red River of the North. The urgency for this grant is due to the fact that the RR water levels have only just started to increase in depth and the predicted maximum flood stage will be reached in late March, 2009. This event is being classified as a 500 yr flood with the predicted hydrograph showing flooding for only 20 to 30 d. This research will test two hypotheses: 1) that flooding-water quality will be impacted by the movement of this water through a large, urban environment; and 2) that post-flooding sediment deposited onto riparian and urban landscapes will have elevated chemical concentrations compared to the underlying soil. Hypothesis 1 will be evaluated by taking water samples upstream and downstream of the major population centers of Fargo-Moorhead and samples will be analyzed for 17â-estradiol (E2) and estrone (E1), total Hg, total gasoline hydrocarbons, total diesel hydrocarbons, nitrate, ammonium, phosphate, pH, electrical conductivity, sulfate, chloride, and total suspended solids. Hypothesis 2 will be evaluated by sampling three low lying areas that were flooded for more than 14 d, which will include a natural riparian area, a community garden or a public park, and an urban lawn. Deposited mass sediment will be determined and the sediment and underlying soil will be quantified for 17â-estradiol (E2) and estrone (E1), total Hg, total gasoline hydrocarbons, total diesel hydrocarbons, nitrate, ammonium, phosphate, pH, electrical conductivity, sulfate, and chloride.The intellectual merit of the proposed research includes an expansion of the knowledge of how flooding-waters from and through both rural landscapes and urban centers influence both water and sediment quality. This work will increase our understanding of how flooding-water quality is impacted as it travels through an urban center of the northern Great Plains and also how the deposited sediment impacts soil quality. Many of the low lying areas within Fargo-Moorhead are used for parks, community gardens, and lawns and providing information about the quality of the post-flood sediment is important to scientific and public communities. Floods are naturally occurring, but the origin of the flooding waters can influence water quality and the quality of soil in low lying areas. The broader impacts of the proposed research include a better understanding of the impact that major floods have on large, urban communities with respect to water quality and the quality of the deposited sediment. Training of a graduate student and disseminating the findings of this research to both public and scientific communities via presentations and published articles will be a primary focus of this research. Local and state officials will be particularly interested in the findings of this work.