Ladies and Gentlemen

My name is Ronald A.Glisci. I live on Laura Drive. I am also a committee member on the Village of Airmont Quality of Life committee.

I would to comment on a problem I perceive with the sanitary sewer system in the Village of Airmont, and how these problems should be considered in allowing changes in zoning and population density.

The information I have seen regarding serious problems with the sanitary sewer system at various locations in Airmont leads me to believe that it would be an irresponsible decision to allow a school, an apartment building, or any structure other than a single family residential home, to be constructed without further study.

QUALIFICATIONS

I am a licensed professional engineer in the State of New York. My training was in environmental engineering. I have personally designed a good portion of the Hicksville sewage collection district in Nassau County, as well as the Southwest Sewer district in Suffolk County, Long Island.

I have prepared sewer design reports for Suffolk County, which involves calculating expected flow rates and determining what size sewers are needed based on existing land use and zoning.

I have also been a construction inspector, supervising the installation of sanitary sewer systems.

PROBLEM

Based on the information I have seen so far, the sanitary sewer system running eastward from S. Monsey Road appears to be seriously undersized for the existing flow rate.

It has been carefully documented, with photographs and detailed record keeping, that raw sewage is chronically sprayed from a manhole at this location, all over the roadway and adjacent areas. This raw sewage then flows by gravity to a nearby brook, which empties into the Saddle River. A similar problem has also been documented in the Hillside Avenue area.

This condition cannot be tolerated. Raw sewage contains pathogenic (disease causing) bacteria and other organisms, which have the potential to create a serious public health hazard.

(My assistant will now present you with envelopes containing these photographs and other pertinent information for your later consideration.)

The overflow shown in the photographs you are now seeing occurs because it appears that the sewer line receiving the flow from this manhole on S. Monsey Road has become too small to handle the peak flow rate coming to it.

The manhole at this location receives flow from two 12’ diameter pressurized force mains in addition to flow from a gravity sewer. That’s why the wastewater sprays out of this manhole, rather than just flows out.

A manhole is simply a concrete structure that allows many sewer lines coming from different directions to be connected. Usually, during the design stage, sewer lines are laid out to flow by gravity. Depending on the topography, however, the system may need to employ pumped sewer lines, known as force mains, in which flow is pumped uphill to a point where the wastewater can again resume flow downhill by gravity. Force mains are used as a last resort due to maintenance costs associated with the pumps and the cost of electricity for pump operation.

It makes no sense to add more flow at this location when the system cannot handle the existing flow without spraying raw sewage all over the roadway.

You may be wondering: Why can’t the sewer handle the flow? What happened?

In my opinion, it appears that the trunk sewer line that the flow from this manhole empties into is running at or near peak capacity already. When the force main pumps come on, the sewage has nowhere to go, the pressure increases, and raw sewage is sprayed out into the environment.

When the sewer system is designed, expected wastewater flow rates are calculated, based on the land use at the time of the design, or on expected future land use. Based on these flow rates calculated, the slope and size of the sewer pipe are determined.

If a sewer is serving a residential street zoned for one house per half acre, the expected flow contribution from that parcel is calculated based on the expected number of people that can reasonably be expected to occupy that residence. Typically you might use 3.7 people per household, times a design flow of say, 200 gallons per capita per day. This is how sewers are sized.

Now, suppose after the system is designed, the land use is changed to allow the construction of an apartment building, or school, or more houses per half acre, or more people per household, or other structures that generate a larger peak sewage flow rate. That sewer line has now become undersized.

If the trunk sewer leaving the manhole at S. Monsey Road is indeed now undersized, any additional flow contributed to the sewer system UPSTREAM of this point will increase the likelihood and frequency at which this manhole sprays sewage into the Saddle River.

The wastewater flow entering this spraying manhole comes from a large area. The area stretches from Route 306 at Route 59, southward to the NJ border, northward along Cherry Lane, and eastward along Route 59 back to Route 306. It appears that this area includes the new large structures currently being erected along Saddle River Road south of Route 59, the subdivision on Stillo, the area of Hillside Avenue, and the parcel adjacent to the manhole on S. Monsey Road, where additional development is also being considered.

Any additional flow generated in this large area through downzoning will increase the flow coming to the manhole in front of 4 S. Monsey Road, and the likelihood and frequency at which this manhole sprays sewage into the Saddle River.

Flow from other high-density development, such as the senior development at Airmont Gardens, and the retreat at Airmont, needs to be considered as well.

To enlarge our perspective even further, this problem may not be limited to the Airmont area exclusively.

It is likely that the flow in the trunk sewer leaving the manhole on S. Monsey Road may be backing up to that point from already overloaded systems downstream of that point, in the Monsey area. As downzoning and over development continue there, there will be nowhere for our wastewater to go except into the Saddle River. The cost for additional sewers or modifications to handle the increased flow could cost hundreds of millions of dollars.

We therefore need to implement a moratorium on all high-density and multi-family usage of residential property in the town of Ramapo until we complete a detailed engineering study, involving looking at the original sewer design flow rates, measuring the existing flow rates, and calculating future expected flow rates to determine exactly how much it will cost the taxpayers to install additional sewer lines to accommodate the additional flow.

This will also reduce any potential liability of the Village of Airmont and the Town of Ramapo for knowingly ignoring the environmental consequences of discharging raw, untreated sewage into public waterways and contaminating a drinking water aquifer.

The time to start this project is now. The place to start is the very next site plan you are asked to review.

Thank you.