Conservation Board

What are wetlands?

Wetlands are areas of saturated soil which may flood or pond (especially in winter), and support specific plants and animals that can live only in wetlands.

Why are natural wetlands beneficial?

They provide a variety of ecological, social, and aesthetic benefits such as:

• Protecting water quality by removing nutrients and chemical contaminants
• Controlling flood waters Serving as essential plant, fish, and wildlife habitats
• Recharging ground and surface waters
• Providing open space and recreational opportunities

What is wetland restoration?

Restoration means reclaiming a degraded wetland to re-establish functions that have been lost by filling or draining. Wetland restoration is the preferred form of impact mitigation because it typically has the greatest chance of successfully establishing natural wetland functions and improving water quality.

What is wetland creation?

Creation means constructing a new wetland, usually by flooding or excavating lands that were not previously occupied by a wetland. This is a difficult task that is generally not as successful as restoring or preserving a wetland.

Why are wetlands being restored and created?

As a means of mitigating wetland losses and meeting the goal of "no net loss" of wetlands. It is hoped that these practices can offset the annual loss of natural wetlands sue to development activities.

What kinds of plants are used in wetland creation and treatment of nonpoint source pollution?

• Cattails Reeds
• Arrowhead
• Rushes
• Sedges
• Bulrushes
• Cordgrass
• Burreed
• Trees (e.g. maples, ashes, elms)
• Woody shrubs (e.g. dogwoods, spicebush, sweet pepperbush)

How do wetlands help improve water quality?

• Pollutants entering natural wetlands are treated by a variety of physical, chemical and biological processes. The following processes filter out pollutants before they reach other waterbodies:
• Settling of sediment and pollutants with Breakdown of pollutants into harmless substances
• Plant uptake

What is a wetland buffer?

In the Town of Yorktown, a wetland buffer is the area that is a 100 foot measured distance from a delineated wetland.

Why are wetland buffers important?

This area of vegetation moderates the temperature of water after it runs off impervious surfaces such as hot pavement or rooftops and filters out excessive nutrients and other non-point source pollutants (like fertilizer, pesticides, or animal waste pathogens). Buffers also slow down the speed of the runoff which helps stabilize streambanks and alleviates flooding. Buffers are an important source of wildlife habitat diversity and provides leaf litter for animals at the bottom of the food chain.

A wetland buffer has three distinct zones:

• Streamside Zone - A minimum of 25 feet wide This is the zone closest to the stream or wetland and it protects the physical and ecological integrity of the stream and wetland. Activities should be highly restricted in this area.
  
  
• Middle Zone - A minimum of 50 feet wide, this zone borders the streamside zone. This zone can incorporate passive recreation (such as hiking trails) and certain stormwater management practices.
  
  
• Outer Zone - A minimum of 25 feet wide, this is the buffer's buffer, which may support turf but preferably native shrubs and trees which are more effective at removing pollutants or heat from stormwater runoff.

What is a watershed?

A watershed encompasses all the areas that contribute water to a water body. For example, the Long Island Sound includes the northern part of Long Island, as well as portions of Westchester County, Connecticut, Massachusetts, New Hampshire and Vermont.

What are the harmful impacts of urbanization on water quality?

Listed are some of the potential impacts:
Massive "pulses" of sediment from construction sites during and after storms. Increased wash off of pollutants (trash and debris, trace metals and nutrients, toxins, gas and oil) Increased stream temperatures Increased algal growth in surface waters from excessive lawn fertilizers.

How can harmful impacts on water quality be reduced?

Best management practices (BMP) is a phrase which means the best available techniques to reduce harmful environmental impacts. BMPs for urban watershed management are typically storage tanks or other devices that temporarily store and/or treat urban runoff to reduce flooding, lower stormwater temperatures, or remove pollutants. BMPs also include natural practices such as grass filter strips that serve to stabilize the soil, filter pollutants and minimize flooding.

What can urban best management practices do for water quality?

Here are some examples of what BMPs can do:
Help reduce the impacts of development. Used alone, however, they are not sufficient to prevent water quality degradation; they should be used together with many other efforts. Prevent flooding by storing stormwater runoff and gradually releasing it downstream. Reduce pollutant concentrations by storing sediment and absorbing nutrients before they reach surface waters such as the Croton Reservoir, Hudson River and Long Island Sound.

What are the different kinds of best management practices?

Here are three general categories of recommended Best Management Practices for water quality treatment:
Infiltration - Infiltration BMP's retain stormwater runoff and allow it to seep into the soil, recharging local groundwater levels, reducing runoff volumes and filtering pollutants. Retention - Retention basins are permanent pools of water that allow for storage of floodwaters, groundwater recharge, streambank erosion control and settling of sediments and attached pollutants. Extended Detention - Extended detention basins temporarily detain stormwater runoff. By detaining stormwater for a length of time, pollutants settle out of the water column and downstream areas receive flood protection. These basins normally remain dry between storms and do not have a permanent pool of water.

Here are two general categories of BMPS for soil stabilization and sediment control:
Erosion Control - A variety of BMPs may be used to stabilize the soil and prevent soil particles from washing off the surface by wind and water. Erosion control BMPs should be the primary weapons in erosion and sediment control plans and programs. Sediment Control - If erosion cannot be prevented, sediment control structures and practices are available to help retain sediment on site and prevent it from washing into streams, wetlands, lakes and ponds. In our area, black silt fences are installed prior to construction to keep sediment on the site and prevent it from entering our waterways.

Conclusion

Planners, developers and engineers can apply BMP designs to protect water quality and enhance the economic value of your home. Creative planning and design of BMPs can improve their function and provide other benefits, such as habitat for fish, birds, and mammals. BMPs can also enhance the aesthetics of new development and reduce maintenance of catch basins and other infrastructure, such as your water and sewer utilities. Most importantly, BMPs, along with other measures, are essential to protect water quality.

What does Impervious mean?

Impervious means that water cannot penetrate the ground surface - instead it flows over the surface directly into catch basins, streams, and wetlands. Nonporous pavement is one example. Development in this area has created a significant amount of impervious surface, including parking lots, buildings and rooftops. New home development, stores and other services are the major cause of increasing imperviousness.

What is Water Quality?

Water quality is determined by the ability of a specific water body to serve its intended use, e.g. drinking, habitat, fishing, swimming, etc. 70% of Yorktown has streams, ponds or lakes that drain into the Croton Watershed which supplies New York City with drinking water.
Why is imperviousness affecting the environment?

When rain water falls onto an impervious surface, it can no longer seep into the ground and be naturally filtered by vegetation and soil. Instead, the water moves over hard impervious surfaces at a much faster rate. Because the water is moving off quicker, it can overwhelm drainage ditches and streams causing flooding. As storm water travels over roads and parking lots, it also picks up pollutants such as oil, grease, bacteria and sediment. Sediment in particular captures harmful elements. These pollutants, now in the stormwater runoff, are delivered directly to streams, lakes and reservoirs.

What effects do we see from stormwater runoff of impervious areas?

The following impacts of imperviousness have been scientifically documented:

• Flooding as more water is delivered directly to water bodies without being slowed down by vegetation or absorbed into the soil.
• Erosion as stream banks are undercut and washed away due to higher and faster flows of water.
• Sedimentation due to upstream soil erosion, which is gradually filling in our lakes, harbors, bays and other water bodies.
• Water temperature increases due to heated stormwater runoff from impervious surfaces.
• Water quality degradation from increased pollution levels such as excessive phosphates and pathogens.
• Habitat loss of certain fish and wildlife species due to water temperature increases, sedimentation, and nitrogen and phosphate loading.

How can we reverse the negative impacts of urban sprawl and imperviousness?

There are some easy ways to alleviate the impacts of imperviousness:

• Divert roof gutters onto vegetated areas instead of paved surfaces or pipes. Minimize the amount of impervious area (e.g. driveways, parking lots, roads, patios, etc.) or use pervious materials.
• Plant trees and shrubs to minimize surface runoff. Create natural buffer areas around wetlands, ponds and streams by creating a "no-mow" zone that filters runoff. Use paving surfaces that allow rainwater to soak into the ground, i.e. wood decking, bricks, or interlocking stones or porous asphalt for driveways.
• Select plants and trees that grow naturally in this area and are not exotic imported plants that may overwhelm a site, such as phragmites. Phragmites is that 8' high grass which grows in wet disturbed areas everywhere and displaces cat-o-nine tails, which muskrats need to eat. Instead put in plants that don't need a great deal of water or fertilizer to survive.
• Use fertilizers, herbicides and pesticides sparingly (or not at all) and according to directions. Use car washes that treat and recycle the wastewater.
• Wash your car on the lawn, instead of over asphalt.
• Check automobiles for leaking oil and other fluids and make repairs, if needed.
• Pick up and properly dispose of pet waste. Biological waste can not only add nutrients, but bacteria to water bodies.

The owner of any parcel located within the Town of Yorktown which relies upon a Separate Sewage Disposal System/On-site Wastewater Treatment System (a septic system) must have the system inspected once every five (5) years. 

An inspection shall mean the evacuation and removal of septage from a Separate Sewage Disposal System/On-site Wastewater Treatment System (have your septic pumped) and subsequent reporting by a Septage Collector that is licensed by the Westchester County Department of Health. 
 

Why is it necessary to have your septic pumped?

Properly designed, constructed, and maintained septic systems can provide long-term, effective treatment of household wastewater. A malfunctioning system can contaminate groundwater that might be a source of drinking water.  Poor septic system maintenance may cause the need for the entire system to be replaced, costing you thousands of dollars.  And if you sell your home, your septic system must be in good working order.
 

What are the signs of septic system failure?

Septic system failure can be noted by these signs:

• Slow drainage or sewage backup in drains or toilets.
• Excessively lush grass growth in the system area, even during dry weather.
• Unpleasant odor in the system area.
• Excessive growth of aquatic weeds or algae in nearby lakes and ponds.
• A slow moving stream near septic leaching areas.

What can you do to limit contamination by septic systems?

Following are some precautions to take to maintain a septic system:

• Pump out the septic tank often - usually every one to 3 years so solids do not build up and flow into the leaching system. Depending on your location, this might be needed annually. If you don't, having the leaching field dug up and reinstalled can be very costly.
• Watch what goes down the drain - the use of a garbage grinder will put 50% more solids into the system. Grease or oil can clog all parts of the system - the pipes, septic tank and leaching system.
• Dispose of household chemicals properly - at the next household hazardous waste collection day in your community (See the Department of Environmental Facilities website for scheduled cleanup days at http://environment.westchestergov.com or call the household Chemical Info-Line at 637-3037).
• Conserve water - by installing low-flow plumbing fixtures and adopting more conservative water use practices. This can extend the life of the system, delay the need for repair and lessen the likelihood of contaminating local surface and ground waters. It can also save repair costs on your water system.
   

How do I maintain my septic system?

Below are several resources that will help you learn more about your septic system and how to maintain it properly.

Additional Resources

• Homeowner's Guide to Septic Systems
• Homeowner's Guide to Septic Systems (Spanish)
• Homeowner's Septic Checklist
• What to Expect During a Septic System Pump-Out
• What to Expect During a Routine Maintenance Inspection
• Westchester County Septic System Rehabilitation & Sewer Connection Program