Sunday, May 7, 2017

Pump talk: Limitations on Hoboken's pumps in flash flooding

The following information on Friday's flash flood is offered by Kurt Gardiner, a Hoboken commissioner on the North Hudson Sewerage Authority.

I am a commissioner on the NHSA representing Hoboken. I would like the share some information that can help people understand what happened on Friday. 

The information below is directly from a Principal Engineer who works for the Sewer Authority.

The pump stations were fully operational during the event.  Based on the analysis of the rain data provided, the storm had between a 5 year and 10 year return period (ie. between a 5 year (1.09 inches in one hour) and 10 year (0.88 inches per hour for 3 hours) event). 

Please refer to the graphic below. The pump station capacity and wet wells were adequate (as may be seen in the H-5 and H-1 graphics below) to pump the flows and were not the issue. The collection system capacity can convey approximately a 2 year storm event. The tide elevation was not an issue and did not affect the pumping capacity of the pumping station. The rain intensity was greater than the collection system can convey to the pumping station.


Kurt Gardiner comments:

The new pump has prevented four of the last five severe rain events from flooding in NW since being operational. This flash flood - storm just produced too much rain too quickly for the collection system to handle. 

I share in the frustration of the flooding that occurred but this event caused problems throughout the region including NYC, Jersey City, West New York and Weehawken. Even with the investments to date Hoboken is still vulnerable to flash flooding. 

If anyone would like to have a constructive dialogue about the flooding you can call me at (917) 543-1187. I am just a commissioner on a nine person board but I represent Hoboken. We have public meetings every third Thursday at 6:30pm. I would encourage anyone who would like to voice their concerns to attend. 

There is a plan for a third pump in the NW but that will not be online for another 5 years. These projects do take time and require layers of planning and regulatory approvals.