Excess fertilizers are polluting our rivers, lakes, and bays. The chemicals in fertilizers are washing into New Jersey’s waterways from hundreds of thousands of lawns in the state. To have clean drinking water and healthy waterways for fishing and swimming in New Jersey, we need to find ways to keep the chemicals in fertilizers from getting into our waterways.

All living things need nutrients to grow and thrive, and plants are no exception. In natural settings like forests and meadows, plants get what they need from the soil as it recycles decaying plant and animal matter. When humans began growing crops for food, they took their cues from nature and returned plant and animal materials to the soil to keep it healthy and productive.

Image of fertilizer on sidewalk next to a lawn area.

Fertilizer improperly applied to a lawn can end up on the sidewalk or road where it can get washed into a local stream. © Jason Kruse

A massive change in practices occurred during the 1900s with the development of petroleum-based synthetic fertilizers, used to give plants a quick fix of nutrients (primarily nitrogen, phosphorus, and potassium).  Over time, both farmers and homeowners began to rely on these synthetic products rather than healthy soil-building practices.

Unfortunately, this shift towards reliance on synthetic, rapid-release fertilizers, coupled with their overuse and misuse, has had serious environmental consequences. The chemicals in fertilizers have become a major source of water pollution, causing unhealthy conditions for aquatic life and for people.

How Fertilizers Pollute Our Waterways

image of man fertilizing the water During rain storms, water running off lawns picks up excess fertilizer on the ground and carries it down storm drains, which often lead directly to streams, rivers, lakes, and bays.

Fertilizer that finds its way into our waterways fuels the too rapid and harmful growth of algae and other aquatic plant life. Sometimes the growth is so explosive it creates an algal “bloom” with millions of organisms discoloring the water. This excessive growth causes an unhealthy increase in the amount of organic matter within a water body, a process called eutrophication.

VIDEO: Eutrophication Explained

Eutrophication from synthetic fertilizer pollution has costly impacts to the environment, economy, and public health in New Jersey.

A lake harmed by excessive algae and plant growth in Elmer, NJ. Photo by Rutgers Cooperative Extension of Salem County

A lake harmed by excessive algae and plant growth in Elmer, NJ.  (Photo by Rutgers Cooperative Extension of Salem County.)

  • Overgrowth of aquatic vegetation can clog waterways, restricting access for fishing, boating, swimming, and other recreational uses.
  • As excessive plant growth dies, its decay uses up oxygen in the water. This can lead to “fish kills” – the death of large numbers of fish when oxygen levels drop too low for them to survive.
  • As oxygen levels drop and other conditions decline, the types of plants and animals that normally live in a waterway can change to less desirable ones.
  • Commercial and recreational fishing catches can decrease as desirable fish species decline in numbers.
  • Certain harmful algal blooms release powerful toxins into the water that can kill fish, shellfish, and even other plants, creating “dead zones” in the water. The toxins can cause health problems or even be deadly to animals and people and raise treatment costs for drinking water.
  • High levels of nitrates (a form of nitrogen) in drinking water can cause “blue baby syndrome” in infants by inhibiting the ability of blood to carry oxygen.

One of the waterways in New Jersey impacted by fertilizer pollution is the Barnegat Bay. Learn how eutrophication is changing the bay and about the efforts of many partners to protect and restore this New Jersey “treasure.”

Take Action

River-Friendly Program:  Become “River-Friendly” certified through a program managed by the Stonybrook-Millstone Watershed Association.
New Jersey’s Fertilizer Law:  How does it impact you?
Fertilize Less: How You Can Make a Difference

Additional Resources

NJDEP Healthy Lawns Healthy Waters
NOAA Nutrient Pollution – Eutrophication
Barnegat Bay Friendly Lawns Video