A state law that limits the percentage of phosphorus in lawn fertilizers and restricts the time of year when and locations where fertilizers can be used went into effect on Jan. 1. The New York State Dishwasher Detergent and Nutrient Runoff Law was enacted to reduce the amount of phosphorus entering and degrading the water and to lower the cost to local governments of removing excess quantities.
The law applies to fertilizer application and would restrict the use of “weed and feed” products that contain phosphorus in amounts over 0.67 percent, unless a soil test showed that a lawn needed phosphorus or in cases where a new lawn is being established.
“I would like to see it go further,” Kevin McAllister, the Peconic Baykeeper, said.
The law, according to a release from Assemblyman Fred W. Thiele Jr., aims to improve recreational and other uses of the state’s waters.
Mr. McAllister said the county put restrictions into effect a few years ago, and while the state is now involved, “We’ve got to do better. . . . We have got to move beyond the trend of the ‘trophy lawn.’ ”
The desire for emerald green, dandelion-free lawns is leading homeowners to pay for excessive applications of fertilizer, he said. Those “hooked on turf,” the baykeeper said, need to learn that a healthy green lawn is possible using organic and sustainable practices that will not threaten water quality.
The State Department of Environmental Conservation states that most soils in New York already contain sufficient phosphorus to support turf grass growth without additional phosphorus from fertilizers, which can account for up to 50 percent of the phosphorus in stormwater runoff.
Phosphorus is expensive for municipalities to remove from wastewater at treatment plants — from $1 to $20 per pound. More than 100 sub-watersheds in the state contain water impaired by phosphorus, according to the D.E.C.’s Web site.
The state’s recent closure of Shinnecock Bay was nitrogen-related, Mr. McAllister said. “We have to curtail the loading of fertilizer,” he said, adding that the way we manage tens of thousands of lawns will make a difference.
Pollutants enter bays and harbors in a number of ways, but primarily through groundwater and stormwater runoff, according to the Nature Conservancy. Fertilizers, pesticides, and herbicides that are used on lawns travel through the soil to the groundwater that flows into our bays and harbors. Phosphorus affects fresh water, and nitrogen affects marine waters.
Mr. McAllister said many of our water bodies have been on the state’s impaired-waters list, which is reassessed every two years, since 2006. In 2010, he said, the entirety of the county’s south shore, including fresh water bodies in East Hampton and Southampton Towns, were placed on the list for either recurring algae blooms or low oxygen levels.
The baykeeper explained that nitrogen from fertilizers triggers the microscopic plants to burst in growth for several weeks. They then decompose and consume dissolved oxygen from the water, resulting in fish and crab kills.
In addition to devastating shellfish populations, overgrowth of algae causes brown tides and interferes with swimming, boating, and fishing, too, the Nature Conservancy said. Even chemicals used on properties far inland can travel long distances underground, ultimately finding their way into bays and wetlands and onto beaches.
In the release, Mr. Thiele reminded East End residents to be mindful of the new state law, which prohibits the application of fertilizers that contain nitrogen, phosphorus, or potassium between Dec. 1 and April 1. If a product does not contain any of the three primary macronutrients, it could be applied during the winter months without violating the law.
“Banning fertilizer in the winter is not going to do it,” Mr. McAllister said. “To really see the reductions, we need to impose more restrictions during the entire year.” The spring and summer are when most homeowners are using lawn products, often as a result of “brilliant marketing” disguised as education by companies such as Scotts, he said.
Although the law also states that “no fertilizers may be applied within 20 feet of surface water,” an exception is made where there is a 10-foot-wide vegetative buffer of planted or naturally occurring vegetation — trees, shrubs, legumes, or grasses — or if the fertilizer is applied using a deflector shield or drop spreader, in which cases applications may be done within three feet of a body of water.
The law does not affect agricultural fertilizer, flower or vegetable gardens, pasture land, land where hay is harvested, the trees, shrubs, and turf grown on turf farms, or any form of agricultural production.
Mr. McAllister is concerned that the law does not apply to agricultural lands, which he said are a significant contributor of nitrogen flushing into groundwater. He said the county’s monitoring of nitrate levels in groundwater downstream from farms is “through the roof.”
The law requires retailers to display phosphorus fertilizer separately from phosphorus-free fertilizer and to post signs notifying customers of the terms of the law. It has no specific disposal requirements for lawn fertilizer containing phosphorus. The law affects organic phosphorus fertilizer, as well, but not compost or liquid compost as long as they do not contain chemically, mechanically, or otherwise manipulated manure or plant matter.
The state banned the sale of phosphorus-containing dishwasher detergents for household use in 2010. The new law prohibits the sale of such detergents for commercial use as of July 1, 2013.
Mr. McAllister said education of property owners about sustainable practices is a priority — the application, for example, of compost that is organic and slowly releases nutrients that are absorbed for growth instead of flushed. He said useful information such as “Four Steps to a Pesticide-Free Lawn” is available online at neighborhood-network.org. The Web site has suggestions such as mowing with the blade set higher, watering infrequently and deeply, seeding with a tall fescue blend, and using organic solutions on weeds and pests. There is also a list of companies that provide landscaping services using sustainable practices.
The Nature Conservancy suggests that homeowners replace high-maintenance sod lawns with native grasses and shrubs that require less fertilization and irrigation.
Mr. McAllister also pointed out that the natural resources of the water bodies on the East End drive the economy here. Regarding polluted, fishless waters that can’t be swum in, he asked, “What will this do to property values?”
“We’ve got to change our evil ways,” the baykeeper said. “This isn’t alarmist, it’s reality.”