Stormwater Ponds

Just as lawn fertilizer helps grass stay green, excess applications turns our ponds green, too. Phosphorus is a nutrient found in fertilizers and acts like food for algae. When excess nutrients enter a stormwater pond, often from lawn fertilizer but from other organic sources too - like grass clippings or leaves - it can cause algae to grow quickly, reducing water clarity and creating foul odors.

A green stormwater pond is a functioning pond. A green stormwater pond may appear to need maintenance, but there are important characteristics to look for that actually indicate it’s functioning as intended:

• Duckweed: Duckweed is a tiny aquatic plant that floats on top of the water.  Duckweed can be identified by a leaf or cluster of leaves with small roots that hang down into the water. Duckweed grows in response to excess nutrients in the waterbody. Duckweed is a valuable food source for waterfowl and turtles, however in over abundance, it can block sunlight and limit oxygen exchange for other aquatic plants.  Duckweed does not signal a need for pond maintenance, but rather the pond is doing it job by capturing nutrient-rich run off and preventing it from entering a lake, river, or wetland.  
• Algae: Pond scum, or filamentous green algae, is a green floating mass which is often found in dense mats resembling wet wool. This alga does not have roots and grows in response to excess nutrients in the waterbody. While this type of algae is non-toxic to humans, homeowners should not handle algae for risk of exposure to harmful bacteria. Cyanobacteria can be toxic and so adults, children, pets should avoid contact where there may be a bloom.
• Odor: Decomposing plant and algae material contributes excess organic material resulting in a foul odor. This type of decay occurs in stagnant and poorly oxygenated water. You may notice the odor typically increases in warm, summer temperatures and subsides over time. 

What can I do to improve water quality in my stormwater pond?

Residents are encouraged to help improve pond health by taking the steps suggested below:

  1. Maintain natural vegetation or sod on all bare areas.
  2. Add native plant species to filter runoff and absorb nutrients.
  3. Use phosphorus-free fertilizer and fertilize only as needed.
  4. Rake up trash, leaves, grass clippings, branches, and other yard waste off the street and curbs. City of Buffalo residents can dispose of debris by transporting to Buffalo's compost facility. 
  5. Use biodegradable soaps for outdoor cleaning and car washing.
  6. Reduce or eliminate winter salt use.
  7. Pick up and properly dispose of pet waste.
  8. Install a rain barrel to harvest rain for use on your lawn or garden.

  City of Buffalo's Responsibility

•  The City of Buffalo maintains (157) stormwater ponds, (9) raingardens, (9) infiltration basins and (1)  underground system. 

•  Inspections:  

   As required by the Municipal Separate Storm Sewer System (MS4) Permit and Stormwater Pollution Prevention Plan (PDF), the City of Buffalo inspects all stormwater ponds and outfalls to determine structural integrity, proper function, and maintenance needs. City-owned stormwater ponds are inspected every five years or 20% annually. Pond inspections typically begin in July.

Maintenance: 

Routine stormwater pond maintenance is necessary to ensure ponds function on a long-term basis. Pond maintenance varies from regular mowing to removing accumulated sediment. The city does not manage ponds for aesthetic purposes including weeds, algae, or odor. The city is not responsible for maintenance or repairs of privately owned ponds. 

City Policy:

Dumping grass clippings, yard waste, and pet waste into a stormwater pond is prohibited. 

Contact Information: 

Please contact the city with the following concerns: 

• Report Maintenance Needs to Dumping of Pollutants: – Online (link) or (763) 682-1181
• Please contact the city if suspicious odors, vegetation staining, or deposits are observed.