Department of Environmental Conservation

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How is the Hudson Doing?

Is the river clean? Swimmable? The answers are mixed. Water quality has improved since the 1960s. Many noxious discharges have ceased, but leftovers from past pollution haunt the Hudson, and new problems are becoming evident.

Should the River Run Clear?

Hudson River muddied by tidal currents

Was the pristine river on which Henry Hudson sailed transparent?

The historical record doesn't say, but the river probably looked muddy then as it does now. Murky conditions are common even in healthy estuaries. Sediment eroded from the watershed washes into estuaries. Tidal currents stir up mud. Salty water pushing in from the sea traps and suspends sediment. Abundant algae can color and cloud the water.

Even clear water may not be clean; bacteria and other organisms that cause disease are invisible. These microorganisms are usually associated with untreated sewage.

Can I Swim in the Hudson?

As cities grew along the Hudson, their sewage discharges increased. In 1965, New York State voters passed a billion dollar Pure Waters Bond Act to fund sewage treatment. In 1972, the Clean Water Act made cleanup a national priority, providing billions more. The Hudson benefited. Off Manhattan, 150 million gallons of raw sewage entered the river daily until 1986, when the North River sewage treatment plant began operating. Bacteria concentrations then declined markedly.

swimmers at Croton Point Park public beach

Does this mean you can safely dive into the Hudson on a hot summer day? Generally, yes. However, official swimming beaches are scarce. At other sites, debris, tidal currents and boat traffic pose dangers. Near Albany, sewage plants do not disinfect their discharges, raising the risk of disease. In New York and other cities, rainfall enters storm drains and then flows to sewage treatment plants. The combined flows from sewers and storm drains often exceed plant capacities, causing overflows of untreated or poorly treated waste into the Hudson.

Can Fish Survive?

Before cleanup, sewage, paper mill discharges, and other organic wastes fed bacteria, swelling their populations. Bacteria consume dissolved oxygen that fish need to breathe. Near Albany in summer, 1970, a study found so little dissolved oxygen that the few fish seen were "swimming slowly at the surface, gulping air, and disturbing an oil film which covered the water surface." After treatment began, 3,314 fish of 27 species were collected there in summer, 1975.

The Clean Water Act also limited industrial discharges. In the years following the law's passage, polluters gradually came into compliance. The Hudson's color at Tarrytown once matched the paint applied to vehicles at a General Motors plant there; now such scenes are unthinkable.

pollution from runoff: trash and oil on river

Today, pollution in runoff is the bigger problem. Rain sweeps automotive fluids and trash from parking lots into the nearest storm drains and eventually the river. Fertilizers, pesticides and animal wastes wash off lawns and farm fields. Soil left bare of plants erodes into streams. Controlling this pollution requires diverse and coordinated efforts by government and private citizens. Watershed planning can be a particularly effective means of addressing such problems.

Toxic Leftovers

fish consumption advisory signs

While discharges have been reduced, a legacy of past pollution remains in river sediments. Most infamous are polychlorinated biphenyls (PCBs), mainly from General Electric plants in Washington County. Moving through food chains, these toxic chemicals become concentrated in fish. Swallowing a few mouthfuls of river water does not significantly expose a person to these pollutants, but regularly eating fish may. For much of the Hudson, New York State's Health Department recommends that children and women of child-bearing age eat no fish and advises other people to limit their fish consumption.

Levels of PCBs have declined since discharges ceased in 1977, but concentrations in fish, birds and mammals remain high enough to affect survival, growth and reproduction. The risks to wildlife and people who eat contaminated fish led the U.S. Environmental Protection Agency to require a cleanup in the Hudson north of Troy; it began in 2009.

Large amounts of PCBs and other persistent contaminants end up in New York Harbor. The operation of the Port of New York and New Jersey, which generates billions of dollars of economic activity and supports more than 228,900 jobs, requires dredging to deepen channels and berths. Dredging and disposal of contaminated mud is very costly.

Looking Ahead

More cleanups are necessary to deal with existing contamination but will not completely eliminate the problem. Having a cleaner river in the future requires prevention - keeping toxic chemicals out of the estuary and its tributaries. Strategies for doing this include altering manufacturing processes, redesigning products, improving industrial maintenance and reusing and recycling potential pollutants.

Unfortunately, researchers are finding worrisome new contaminants in the river, among them antibiotics and hormones used in drugs and personal care products. Scientists are just beginning to look at how these substances affect fish and public health. In addition, regulations must be updated to deal with potential impacts of new chemicals now in common use.

Finally, our sewage treatment infrastructure needs attention. Plants built in the 1970s are nearing the end of their design life, while population growth stresses their capacity. In the Hudson Valley outside of New York City, an investment of nearly $1.6 billion will be needed to maintain water quality over the next 20 years. In its New York State Wastewater Infrastructure Needs report DEC estimated that the investment necessary statewide rises to $36 billion.