are we concerned about Phosphorus?
Why is Ann Arbor
banning the use of phosphorus containing fertilizers?
in surface waters can lead to excess plant growth which can reduce
available oxygen for fish and other aquatic organisms.
Under certain conditions,
algal blooms can form, reducing availability of light and oxygen, resulting
in fish kills .
Algal blooms also
effect recreational water activities.
Runoff from single
and multi-family dwellings in Ann Arbor is a significant source phosphorus
in the Huron River.
Research shows that
in most areas of Ann Arbor, there are sufficient levels of phosphorus already
in the soil, and phosphorus additives are not needed. In fact, 86%
of 913 soil samples taken in Washtenaw county indicate that no additional
phosphorus is needed for successful turf growth.
100% compliance with
the phosphorus-free mandate would reduce phosphorus loading in the Huron
River by 560 lbs. per year, which is decrease of 22%.
The ban on phosphorus
containing fertilizers will only apply to fertilizers applied to turf.
One may still use fertilizers containing phosphorus in a flower or vegetable
can I do to reduce phosphorus loading in the Huron River?
courtesy of National Wildlife Foundation
Between 9 and 34%
of phosphorus loads going to municipal wastewater treatment plants originates
from automatic dishwashing detergents! Use phosphate-free
(Seventh Generation Powder) or low-phosphate (Palmolive Gel, 1.6%)
automatic dishwashing detergents.
When you mow your
lawn, leave the clippings on your lawn, as this will return the phosphorus
back to your turf. Likewise, do not allow the clippings to accumulate
on pavements, as the clippings will be washed into the sewage system, increasing
the phosphorus load.
Another source of
phosphorus in your household is food waste, such as the scraps of food
you wash down your sink and grind up in in your garbage disposal (even
the phosphoric acid used in soft drinks contains high amounts of phosphorous).
Instead of sending this phosphorus-rich material to your community's wastewater
treatment, and then to the Huron River, compost it!
An effective way
to both reduce the need for fertilizer, and provide a valuable backyard
micro-habitat for wildlife is to allow native species to reclaim your lawn
(if local ordinances allow) or by creating a natural wetland
(photo of Pfizer wetland). Even creating an aesthetic border
around your yard can help our waterways and open your yard to butterflies,
birds, and other fauna. The National
Wildlife Federation has great site about creating natural habitats
in your home, community, and school.
other communities have banned phosphorus?
Many other cities
are recognizing the need for reducing phosphorus loading to their watersheds
and are thus mandating the reduction or elimination of use of phosphorus
containing fertilizers. Such communities include, but are not limited