Blue Mountain Birch Cove Lakes Water Quality Baseline data

In April 2021, a team of volunteers conducted a water quality survey by canoe of 21 lakes within the conceptual boundary of the Blue Mountain Birch Cove Regional Urban Wilderness Park. Variables measured included Secchi depth (a measure of turbidity), dissolved oxygen, conductivity, pH and total phosphorus. Vertical profiles indicated that all lakes were well mixed from surface to bottom at the time of sampling. Mean values of each variable were calculated for each lake. Secchi depths ranged from 1.5 to 3.0 m, dissolved oxygen ranged from 80 to 100 %, conductivity ranged from 14 to 187 μS/cm, ph ranged from 3.61 to 6.12 and total phosphorus ranged from 4 to 9 μg/l. The highest values for conductivity occurred in the lower part of the Kearney Run watershed and indicate the addition of road salt and other pollutants from surrounding development. The lowest values for pH can most likely be attributed to widespread acid precipitation during the latter part of the twentieth century. Overall, the water quality of the lakes appears excellent but continued monitoring is recommended, especially in the lakes in the lower part of the Kearney Run Watershed such as Susies, Quarry, Washmill and Kearney lakes which are currently the most affected by development.

2021年4月，一支志愿者团队乘坐独木舟，对蓝山桦湾都市荒野区域公园（Blue Mountain Birch Cove Regional Urban Wilderness Park）概念边界内的21个湖泊开展了水质调查。本次测量的指标包括塞氏深度（Secchi depth，表征水体浊度的指标）、溶解氧、电导率、pH值以及总磷。垂直剖面监测数据显示，采样时段内所有湖泊均实现了表层至底层的充分混合。研究人员为每个湖泊计算了各监测指标的平均值。各指标的取值范围如下：塞氏深度为1.5至3.0米，溶解氧为80%至100%，电导率为14至187 μS/cm，pH值为3.61至6.12，总磷为4至9 μg/l。电导率的最高值出现在卡尼溪（Kearney Run）流域下游区域，该结果表明周边开发活动带来了道路融雪盐及其他污染物。pH值的最低值大概率可归因于20世纪后期广泛存在的酸性沉降。整体而言，本次调查涉及的湖泊水质表现优异，但仍建议开展持续监测，尤其是卡尼溪流域下游的苏西湖（Susies）、采石场湖（Quarry）、洗磨湖（Washmill）以及卡尼湖（Kearney），这些湖泊目前受开发活动影响最为显著。