Betsy White, Advocacy Director

Thanks to the WRWA WIF (Watershed Improvement Fund), we have been able to consecutively sample three major ponds in our watershed for water quality over the past six years. These ponds are Cockeast, Forge, and Adamsville. Why do we sample? Because ponds such as these often act like "canaries in a coal mine" for a watershed. If they start to show signs of bad health (i.e. nutrient enrichment), then we know that it is only a matter of time before it effects downstream water bodies such as the Westport River. To prevent this, the sources of the pollutant need to be sought out and their contributions decreased or eliminated. A water quality sampling program such as this is a proactive, inexpensive way to monitor and address nitrogen and its management.

It is important to monitor water quality in consecutive years in order to determine if there are any trends or changes occurring over time. For example, the culvert pipe leading from Cockeast pond to the Harbor was reset in December of 2010, allowing water and marine life to flow more easily in to and out of the pond. Fortunately, WRWA had sampled the pond the three years prior to this project, and we have continued to sample the pond in the last three years. The pipe was placed lower in the channel, which increased tidal exchange between the pond and the harbor. This has resulted in lower water levels, especially when water is moving out (ebbing) of the pond, and higher salinities, moving the ecosystem to more of a brackish salt pond environment rather than a freshwater pond environment.  Nitrogen concentrations have decreased moderately since 2010, although they are still not at a healthy level. Water clarity has also increased, and because the pond is relatively shallow, this has meant that more sunlight is able to reach the bottom and promote the growth of bottom-growing algae.  We will need to continue to sample Cockeast Pond in order to tell if the water quality is really decreasing since the culvert project.

Adamsville Pond is another example of having available water quality data before and after a project. The pond has been sampled by WRWA since 2008, and has seen many changes in water levels over those years. The nitrogen concentrations in the pond remain above healthy levels, but are showing a slight downward trend.  In the summer of 2013, the pond dried up due to water leaking past the old dam structure. Because of this, we were unable to collect water samples from the pond. However, with renewed sampling in 2014, the effects of this drying event on water quality can be measured and nitrogen can continue to be monitored.   

Similar to the other two ponds, Forge Pond has shown a decrease in nitrogen concentrations over the past few years, but they still remain relatively high in terms of water quality. In all the ponds, phosphate levels remain low, which is not unusual in waterbodies surrounded by wooded areas, as are Adamsville Pond and Forge Pond, or in saline ecosystems, such as Cockeast Pond.

Each pond can be considered a "canary" in the area of town in which it is located. Currently they are all showing signs of moderate nutrient enrichment, which may indicate a pollution problem in their area. However, the slight downward trend in nitrogen levels recently may also indicate some good things happening. We will continue to be proactive and keep a close eye on water quality of these important ponds.