ACTION TO BE TAKEN

Governing Body supports purchases and actions

needed to help resolve this issue

Due to the low lying nature of the neighborhood, West Park is frequently inundated with coastal flooding.

The West Park Neighborhood of the Borough of Rumson is a small peninsula situated South of Rumson Road and bound by the Shrewsbury River to the East and Oyster Bay (Polly’s Pond) to the West. The neighborhood is comprised of approximately 180 residential properties located in a FEMA mapped Special Flood Hazard Area. The neighborhood was severely impacted during Superstorm Sandy and has rebuilt with greater resiliency to major events. 

History

During the ’92 Nor’ Easter the West Park neighborhood suffered major flood damages resulting in many of the homes being lifted or replaced.  As storm recovery efforts were nearing complete, the Borough initiated a program to reconstruct and elevate the local roadway system in West Park. Waterman Avenue, Warren Street, and South Ward Avenue all south of Grant Avenue were reconstructed and elevated to allow for better drainage characteristics and to reduce the nuisance flooding experienced during high tide events.  The existing drainage system was abandoned and replaced with a new drainage system which is in operation today. At the time of project design, the lowest elevation of the street or corresponding drainage inlet was equal to or slightly higher than the highest predicted tide of that calendar year. (Editor’s Note – The information presented above was relayed to David Marks, Borough Engineer by the West Park Project Engineer prior to his retirement.)

Post Superstorm Sandy, the issue of frequent nuisance flooding which impacted daily life in West Park was brought to the attention of the Rumson Mayor and Council.  The Governing Body took action on the matter and had check valves installed on the existing drainage piping. A check valve installed on the drainage system should prevent the flow of tidal water into the drainage system and allow for rainwater from the street to drain into the Shrewsbury River or Polly’s Pond.  When the tide is high, the valve remains in a closed position which may also prevent the draining of rainwater from the roadway. The responses received after the valves were installed positive with residents claiming the conditions had improved. 

Recently, residents began contacting the Borough regarding the roadways being flooded more often and for longer periods of time. Our Borough Engineer began investigating the matter and tried reconciling resident reports to tidal data recorded by Stevens Flood Advisory System at Davidson Laboratory for the Shrewsbury River at Sea Bright, NJ and coastal storm information.

Progress Updates:

June 4, 2024 Update

DPW began the removal of the existing check valves along Oyster Bay.  The valve at the end of Waterman Avenue was completely removed and the valve at the end of Grant Avenue was prepared for removal.  As tides permit, DPW will return to remove the remaining valves along Oyster Bay.

May 31, 2024 Update

Wapro Representatives met with the Borough Engineer and Superintendent of Public Works to review the Borough’s order for replacement valves.  They also reviewed installation procedures while onsite.  The discussion was very productive and reaffirmed many of the decisions made to date, with some helpful guidance on installation and supplemental materials required for the valve installation.

May 23, 2024 Update

After inspection of the drainage configuration and the potential timing of the next tidal evaluation, the Borough Engineer has moved forward with the purchase of three replacement storm water check valves for the West Park neighborhood. This purchase will replace check valves at the end of Grant Avenue, Waterman Avenue and the midblock of Warren Street. While the Borough awaits the delivery, the valves on the Oyster Bay side of West Park will be removed and the drainage pipes will be cleaned and robotically inspected. The remaining valve at the midblock location of Waterman Avenue is currently operational at this time.

May 10, 2024 Update

The Borough Engineer conducted a high tide inspection of the valves and drainage system on April 11, 2024 at approximately 11 am.  At the time of the inspections, the drainage system on Grant Avenue and at the end of Waterman Avenue leading into Oyster Bay were both flooded. The Governing Body has directed the Borough Engineer to proceed with acquiring the two replacement valves for Grant Avenue and the end of Waterman Avenue. 

The Warren Avenue and Waterman Avenue mid-block drainage systems leading out to Oyster Bay and Shrewsbury River, respectively, were both free from flood waters during the April 11th inspection.  To determine if the tide elevation was high enough to back up the drainage system at those locations, the Borough Engineer utilized a self-leveling rotary laser to determine the difference in elevation between Oyster Bay and the drainage on Warren Street.  At the time of the inspection, the Oyster Bay water elevation was approximately 6” below the top of the bulkhead at 26 Warren Street and there was no water in that portion of the drainage system on Warren Street.  From that survey, it was determined the bulkhead is higher than the top of the catch basin on Warren Street by 3-1/4” and the catch basin is 38” deep when measured from the top of curb.  What this ultimately means is that the mid-block valve on Warren Street is functioning to prevent the flow of tidal water into the drainage system.  This holds true for the mid-block valve on Waterman Avenue as the Shrewsbury River was well above the valve. The sketch below attempts to illustrate the survey completed by the Borough Engineer for the mid-block valve on Warren Street.

What could not be determined from the April 11, 2024 investigation, is whether the mid-block valves are properly functioning to completely discharge water from the drainage system.  In order to determine that function of the valve, the Borough Engineer will need to conduct an outgoing tide inspection, when tides are elevated enough to cause roadway flooding.  Once that evaluation is complete, the Borough can confidently proceed with the necessary valve replacement.

Stevens Flood Advisory System at Davidson Laboratory for April 10 -12, 2024

April 1, 2024 Update

With West Park residents recently attending two Council Meetings, it was determined the most effective means of communicating project progress would be the creation of a webpage dedicated to this matter.  As information becomes available, updates will get posted here.

The Borough Engineer has met with representatives from Wapro a check valve company specializing in this type of project application. The Wapro representatives recommended the Wastop valve in various sizes to be installed on the drainage discharge pipes into the Shrewsbury River and Polly’s Pond. Wapro is developing the pricing and the Borough is researching the acquisition programs available to comply with NJ State Purchasing Laws.

The Borough Engineer and Superintendent of Public Works conducted field inspections on March 21, 2024 during a very low tide. The photos below show the drainage discharge pipes at the end of Grant Avenue, mid-block of Warren Street, end of Waterman Avenue, and mid-block Waterman Avenue.  From the visual inspection, the valves appear to be opening and closing and are free of debris.

The next inspection will need to be conducted during an incoming tide to see which valves are allowing tidal water into the drainage system. That follow-up inspection will likely be conducted the week of April 8th or April 15th depending on weather and tide schedules and elevations.

As discussed during one of the Public Comment sessions during a Council Meeting, the NJDEP FRAMES report can be found which discusses short and long term approaches to sea level rise and community resiliency throughout the Two River Area.

NJDEP Frames Report

https://www.nj.gov/dep/bcrp/njframes.html

Rumson Borough Officials and Staff participated in the various stages of developing the NJDEP FRAMES report which included the Getting to Resilience (GTR) initiative with the Jacques Cousteau National Estuarine Research Reserve.

Recent Coastal Flooding Observations

During the January 13, 2024 Coastal Storm Event, tide elevations were recorded by Stevens Flood Advisory System at Davidson Laboratory for the Shrewsbury River at Sea Bright, NJ approximating 5.0’ NAVD88. This is one of the most significant coastal flooding events the Borough has experienced in recent years.

Stevens Flood Advisory System

Other Resources

NOAA Tides & Currents – Sea Bright Tidal Station Datum

Sea Level Rise Mapping Tool, FAQ

The flooding elevations experienced on the January 13, 2024 approximate to a 3’ sea level rise above Mean Higher High Water (MHHW) as shown on the NOAA Sea Level Rise Viewer (screenshot below).

Dr. David A. Robinson, The New Jersey State Climatologist, issues monthly Climate Summary and Seasonal Recaps related to weather activity using a network of weather data collection points throughout the State.  That monthly data is utilized in his comparison of the weather records collected in the State since 1895.  When applicable, Dr. Robinson compares the past month’s weather to the 129 years of available data. The State experienced an average precipitation of 7.76” which is the 3rd wettest March, on record, since 1895.  Locally, the data logger at Monmouth Park Race Track in Oceanport posted 10.27” of rain in March.

The table below, illustrates the departure above or below the State average monthly precipitation, with notations when record setting precipitation occurred over the 129 years of data collection.

For more detailed information regarding Dr. Robinson’s Climate reports and his work through Rutgers University with the Office of the New Jersey State Climatologist, please visit https://climate.rutgers.edu/stateclim/?section=home&target=home.

The Borough of Rumson is sharing the information with our community to highlight the importance of Stormwater and Groundwater Management.  Many of the recent inquiries fielded by our Borough Engineer and Borough Staff have been directly related to the significant rain events and the coinciding high groundwater levels experienced in recent months.  The groundwater elevations within the Borough may be causing your or your neighbors sump pumps to run frequently.   The sump pump discharge should not be directed towards neighboring properties, whenever possible they should be directed onto your lawn, into a storm drain collection system or towards the street. 

Connecting a sump pump, roof leader or other type of Stormwater drain to the sanitary sewer system is illegal and must be disconnected immediately.  The added water into the Borough sanitary sewer system creates an undue burden on the infrastructure which can lead to equipment failure, added operating and personnel costs, and possible sewer discharge into the environment.  The Borough of Rumson is a customer to the Two Rivers Water Reclamation Authority (TRWRA) and pays a surcharge for sewer flows in excess of our annual, daily allotment.  With this extended period of wet weather conditions, the Borough has experienced intermittent sanitary sewer flows in excess of 3x our typical sewer flows to TRWRA

The Borough will continue on our Sanitary Sewer Rehabilitation Program to clean, televise inspect, and seal leaking pipe joints within the Municipal Right-of-Way.  The completed phases of the project demonstrated considerable success at reducing groundwater infiltration into the sewer system, but only account for a fraction of the 42 miles of sewer pipe in the Borough.  If you have a sump pump, roof leader, yard drain, outdoor shower or other illicit connection to the sewer system, we request that you make provisions to have the connection eliminated immediately.  If you need support in finding the connection or finding a suitable means of discharging the water, please contact the Borough Offices.