Recently I learned about the Salt Ponds Coalition, a local non-profit that among other things has been measuring water quality for about 28 years! Among their many efforts, they publish a seasonal newsletter, the latest of which features our pond! It turns out water quality is often measured as an “Aquatic Health Index” (AHI) which factors a few things (bacteria, nitrates, etc) into a score from 0 to 100, where higher numbers are better quality water. You can read a bit more about pond pollution on the SPC site, here.
The good news is that our pond generally scores “good,” and that’s better than some of the other ponds. This is thanks mostly to the breachway. The pond water quality has remained pretty steady for most of the decade, occasionally scoring “fair” at some of the test sites.
The SPC writes in their summer newsletter:
Figure 2 is a plot of average AHI values for sampling sites in Quonochontaug Pond. Again, these values are averages of individual parameter AHI values at each site. The AHI scores at all of the sites we tested declined, but none changed from their “good” or “fair” category from 2011. There were no improving or declining trends observable from linear trendlines for the data—all r2 values were at or near 0.00. That said, the degree of sedimentation of the pond from sand coming in through the breachway continues to be of concern to SPC, as sand coming through the breachway smothers bottom habitat and restricts circulation in the pond. Left unchecked, this situation could have a detrimental effect on water quality in the pond, especially in the western basin where replenishment from clean ocean water is already restricted. Dredging of the Quonochontaug breachway and habitat restoration are the third phase of the ACOE South Shore Restoration Project, after Winnapaug Pond, and is likely at least 4-5 years away. We will keep you informed as we learn more.
Figure 2 is a chart, which I’ve included below.
Quonochontaug water quality