Dye Concentration at Station FL4 Downstream of Lock and Dam 14 near Pleasant Valley, Iowa (June 2017)

These data were collected in support of a multi-agency effort to evaluate the feasibility of using carbon dioxide to create a barrier and prevent upstream passage of invasive fish through navigational locks. The auxiliary lock at Lock and Dam 14 on the Mississippi River near Pleasant Valley, Iowa, was chosen for a field-scale trial of the carbon dioxide barrier to be conducted in 2018. In preparation for this trial, the mixing in the lock chamber during routine operations and the fate and transport of lock water released to the pool downstream was studied using a dye tracer. In June 2017, the U.S. Geological Survey (USGS) performed two injections of Rhodamine WT dye into the auxiliary lock chamber as the lock was filled. The dye was injected directly into the fill water at the upstream valves on both sides of the lock. The first injection of 0.82 liters of Rhodamine WT (0.41 liters per intake) occurred at 9:50 am on June 13, 2017. The second injection of 0.25 liters of Rhodamine WT (0.125 liters per intake) occurred at 12:11 pm on June 13, 2017. Both injections started approximately 1 minute after filling of the lock began and the injections took approximately 2 minutes to complete. The total time to fill the auxiliary lock in both cases was 6 minutes. All times are in Central Daylight Time (CDT). The distribution of dye within the lock chamber and downstream of the lock was measured using eight Turner Designs C3 submersible fluorometers (1 in vertical profiling mode in the lock chamber, 6 at fixed locations downstream of the lock, and 1 mounted on a mobile survey vessel). This data release is comprised of a time series of dye concentration at a fixed location downstream of the auxiliary lock chamber at Lock and Dam 14 on the Mississippi River near Pleasant Valley, Iowa, on June 13, 2017 and June 14, 2017. The measurements were obtained using a Turner Designs C3 submersible fluorormeter (SN 2300175) deployed at a fixed depth below the water surface. All parameters (dye concentration, turbidity, and temperature) were sampled at 5-second intervals.

本数据集为支撑一项多机构合作研究项目采集所得，该项目旨在评估利用二氧化碳构建阻隔屏障、防止入侵鱼类经通航船闸向上游穿越的可行性。美国艾奥瓦州普莱森特谷附近密西西比河14号船闸与大坝的辅助船闸，被选为2018年二氧化碳阻隔屏障现场试验的实施场地。为筹备本次试验，研究团队通过染料示踪剂开展了两项研究：一是常规作业过程中船闸闸室的水流混合特征，二是释放至下游河段的船闸水的归宿与输运特性。2017年6月，美国地质调查局（U.S. Geological Survey, USGS）在辅助船闸充水期间，先后两次向闸室注入罗丹明WT（Rhodamine WT）染料。染料被直接注入船闸两侧上游阀门的充水水流中。第一次注入于2017年6月13日上午9:50进行，注入总量为0.82升罗丹明WT（每个进水口注入0.41升）；第二次注入于当日12:11进行，注入总量为0.25升罗丹明WT（每个进水口注入0.125升）。两次注入均在船闸开始充水约1分钟后启动，单轮注入耗时约2分钟，两次辅助船闸充水总时长均为6分钟。所有时间均采用中部夏令时（Central Daylight Time, CDT）标注。研究团队共部署8台特纳设计C3型（Turner Designs C3）水下荧光计开展监测：1台在闸室内以垂直剖面模式采集数据，6台固定布置在船闸下游河段的监测点位，剩余1台安装于移动测量船上。本数据发布内容包含2017年6月13日与14日，在艾奥瓦州普莱森特谷附近密西西比河14号船闸与大坝辅助船闸下游某固定点位采集的染料浓度时间序列数据。本次监测采用序列号为2300175的特纳设计C3型水下荧光计，部署于水面以下固定深度处。所有监测参数（染料浓度、浊度与水温）均以5秒为间隔进行采样。