Jamaica Bay
By Jessica Bod

    Jamaica Bay is a coastline of tidal wetlands that extends for over 60 miles along the south shore of Long Island. It includes open waters, tidal wetlands, meadows, shrub lands and some pieces of coastal forest. In addition, it functions as a recreational area in New York City, and host a vast array of wildlife.

    Before it was settled, Jamaica Bay possessed about 16,000 acres of wetlands. A mere 4000 acres survive, as wetland filling for various human activities has diminished the Bay. Jamaica Bay wetlands were filled to create sites for garbage disposal, marina communities, the Belt Parkway, and JFK airport. Jamaica Bay wetlands continue to disappear even without filling, although authorities disagree on the exact cause of this phenomenon. 10-20% of the wetlands have been lost since 1975 simply due to geological forces.
Contamination of Jamaica Bay due to sewage has affected the Bay's fish population of about 49 species. Organic contaminants from sewage cause young fish to have an estrogen response, which actually reduces reproduction in fish and benthic populations.
  Several factors affect the water quality of Jamaica Bay. The bay serves as an outlet for four wastewater pollution control plants. It is susceptible to sewage runoff during heavy rains, and receives little freshwater flow to counteract this runoff. During construction projects in the area, including the building of JFK airport, Jamaica Bay was dredged to generate landfill. This greatly upset the sediment composition in the bay, and created deep channels where there had been no channels before.
   The surface dissolved oxygen (DO) levels in Jamaica Bay have been high enough to be able to support aquatic life for the past 30 years, and have been improving over time. Dissolved oxygen on the bottom of Jamaica Bay is another story, and have fallen below New York State standard levels (5 mg/l) from time to time, including periods in 2002. The differences between surface and bottom DO levels have increased over the past 15 years, while the chlorophyll a levels and murkiness have increased. This suggests that the decreased DO of the deeper water is due to the inability of sunlight to reach these depths, thus hindering the ability of oxygen-producing photosynthetic organisms to reside there.


    In 2002, from May to September, ten sites on Jamaica Bay were sampled for both surface and bottom oxygen levels, with 141 samples taken between. The average DO levels of Jamaica Bay were 8.3 mg/l at the surface, and 6.9 mg/l at the bottom. These values are above the standard level to support aquatic life. 24% of samples taken in Jamaica Bay fell below the standard of 5 mg/l, most notably in the test site known as Grassy Bay, which has been heavily affected by dredging. Another problem area was that of Bergen Basin, which is located 500 meters from the Jamaica wastewater pollution control plant.

    Fecal coliform levels in Jamaica Bay have dropped significantly over the past 30 years. This decline is attributed to improvements made on wastewater pollution control plants. In 2002, high rainfall in August caused some elevated fecal coliform due to sewage runoff.


DO and Fecal Coliform Results for Jamaica Bay for 2002:
 

Station

Code

Location

Dissolved Oxygen (mg/l)

Fecal Coliform

Mean

Minimum

Summer Geometric Mean

Maximum

Surface

Bottom

Surface

Bottom
J1
Rockaway Inlet
8.4
7.7
5.5
5.7
10
400
 
J2
Mill Basin
8.0
6.9
4.7
4.4
15
400
 
J3
Canarsie Pier
8.7
7.0
5.0
3.9
55
800
 
J5
Railroad Tressle
8.0
 
7.5
4.1
4.2
27
800
 
J7
Bergen Basin
8.0
4.7
3.1
1.0
168
948
 
J8
Spring Creek
7.2
6.1
3.7
2.8
95
1108
 
J9A
Fresh Creek
8.1
6.9
4.2
3.1
64
800
 
J11
Sheephead Bay
9.4
7.9
6.0
5.3
126
588
 
J12
Grassy Bay
9.1
2.8
3.6
0.4
49
772
 

    Jamaica Bay has the most elevated algal activity in the entire New York Harbor area. Therefore, chlorophyll a levels are relatively high. Over the past 7 years, the chlorophyll a range has been higher than in previous years. This is attributed to a significant growth in phytoplankton.

The clarity of the water in Jamaica Bay is also declining, with the year 2002 showing significantly more turbid water than in previous years. In early July, a major algal bloom occurs in Jamaica Bay, causing water clarity to decline.
Research in Jamaica Bay continues, as scientists attempt to understand and preserve this rich home of wildlife and recreational center for New Yorkers.

 
 

Sources: