Groundwater - surface water interactions in coastal and inland settings

该项目侧重于沿海和内陆地区地表水和地下水之间的相互作用。地下水排放可能是向近岸海洋环境输送过量营养物质或重金属等污染物的重要途径。由于潮汐波动和涨潮时海水每天流入沿海含水层，这一环境在水文上非常动态。该项目的一个要素是增强我们测量水和溶解化学物质在这个重要界面上交换的空间和时间变化的能力。该研究还检查了控制污染物稀释程度的因素，当羽流穿过含水层的潮汐混合带时，在它排放到水生受体居住的海滩表面之前。在内陆地区，该项目将研究地下水流量、取用地下水供水以及在低流量条件下对河流流量的影响之间的相互作用。在不列颠哥伦比亚省的弗雷泽河谷，地下水的长期可持续利用很可能会受到低流量条件下地下水提取对河流栖息地的累积影响的限制。将发展建模方法，提供大大改进的能力，以预测地下水开发对水流的大规模长期影响。在本研究的第三个组成部分中，我们将检验现有理论描述水通过部分饱和、非均质多孔介质渗透的能力。这项研究将集中在一个独特的数据集上，该数据集已被收集来描述水在废石堆中的运动，这些废石堆几乎在所有矿场都有发现。这项研究将有助于提高了解和管理与矿山作业和关闭有关的对地下水和地表水的长期影响的能力。它也将适用于涉及渗透到粗质、非均质沉积物的其他设置。

This project focusses on the interactions between surface water and groundwater in both coastal and inland settings. Groundwater discharge can be an important pathway for delivering either excess nutrients, or contaminants such as heavy metals, to the near-shore marine environment.  This setting is hydrologically very dynamic, as a result of tidal fluctuations and the daily movement of seawater into coastal aquifers at high tide.  One element of the project is designed to enhance our capability to measure the spatial and temporal variations in the exchange of water and dissolved chemicals across this important interface.  The study also examines the factors controlling the extent of contaminant dilution as a plume moves through the tidal mixing zone in an aquifer, before it discharges on the beach face where aquatic receptors reside.  In inland settings, the project will examine the interactions between groundwater flow, groundwater withdrawals for water supply, and impacts on stream flow during low-flow conditions.  In the Fraser Valley of British Columbia, it is likely that the long-term sustainable use of groundwater will be constrained by the cumulative effects of groundwater withdrawals on stream habitat during low-flow conditions.  Modeling approaches will be developed that provide a much-improved capability for projecting large-scale, long term impacts of groundwater development on streamflow. In a third component of this study, we will be examining the capability of existing theories to describe water infiltration through partially saturated, heterogeneous porous media.  This study will focus on a unique data set that has been collected to describe the movement of water through waste rock piles, which are found at nearly all mine sites.  This study will contribute to an improved capability for understanding and managing the long-term impacts on groundwater and surface water associated with mine operations and closure. It will also be applicable to other settings that involve infiltration into coarse, heterogeneous sediments.