—Is Water Quality Improving? —
[Excerpts from the Is Water Quality Improving? marker]
The Eastern oyster has a long history as being a commercially and ecologically important species in the Delaware Estuary. As far back as the early 1800s, Eastern oysters found in the Delaware Bay were known for their unique taste and high quality meat. They were extremely popular on the oyster market, and had a significant economic importance to the bayshore communities of Delaware and New Jersey.
Throughout the early 1900s, annual oyster landings ranged from one million to two million bushels. In the 1950s, however, oyster production was dramatically reduced due to a parasite called MSX. By 1960, only 49,000 bushels were harvested in the Delaware Bay. Gradually, the industry rebounded as the seedbeds recovered in the late 1960s and early 1970s and native oysters developed some resistance to the disease. Unfortunately, in 1990, a new problem surfaced in several locations on the New Jersey side of the Delaware Bay. A new parasite, known as Dermo, spread over much of the Eastern bay causing heavy losses of planted and seeded oysters.
Is Water Quality Improving in the Delaware Estuary?
Yes! Today's water quality standards and tighter controls have resulted in a
much cleaner [Delaware] Estuary as compared to a few decades ago. New techniques allow us to locate sources of pollution and find ways to prevent pollution from entering our rivers and streams. Enforcement of the Clean Water Act, which was passed by Congress in 1972, and the construction of wastewater treatment facilities, have both gone a long way toward improving water quality.
Water quality is an important issue in the Delaware Estuary because of the heavy demands for drinking water, industrial water use, and recreational and commercial fisheries. An excellent indicator of water quality is fish population. We know the quality of the water is improving because of types and variety of fish species that can be found in the Delaware Estuary are increasing. One such indicator species is the striped bass.
As early as the 1700s, water quality in the Estuary was recognized as a problem. In its darkest days, the Delaware Estuary was so badly polluted that little or no oxygen remained in the water to support fish populations. Untreated municipal sewage and industrial waste led to low dissolved oxygen levels in the more industrial areas of the Estuary. Gaseous odors, released from sewage in the water, tarnished ships, sickened sailors, and turned nearby houses yellow in color.
Our water has greatly improved due to the success of the Clean Water Act, which regulates point sources of pollution. Point source pollution is pollution known to come from a distinct source, such as an industrial discharge pipe.
Yet, despite our great strides in improving water quality, challenges still remain. The Estuary faces threats from toxi[n]s, oil spills, and human development. One of the greatest threats to water quality in the Delaware Estuary is from "nonpoint source," or stormwater runoff.