Storm Response

Tropical Storm Henri approaching the U.S. East Coast. Photo Credit: Nasa Earth Observatory.

Recently, Tropical Storm Henri dropped a record amount of precipitation on the five boroughs and portions of the upstate watershed. To keep essential services running during such conditions, we must prepare critical infrastructure and have contingency plans in place.

Here is how our water supply, water and sewer operations, and wastewater treatment staff prepare for a storm like Henri:

Storm clouds over Ashokan Reservoir

Water Supply

Staff that work on our upstate water supply manage 19 reservoirs and three controlled lakes that span a 2,000 square mile watershed. They are responsible for supplying the drinking water of more than 9 MILLION New Yorkers. When a storm like Henri knocks on our door, they:

• implement operational changes to the reservoirs to create more storage space for the anticipated rainfall
• ensure water treatment supplies and staff are pre-positioned and prepared for downed trees and flooding across the watershed
• adjust processes at our seven upstate wastewater treatment plants to accommodate higher inflows

An NYC catch basin on a rainy day

Water and Sewer Operations

Our water and sewer operations staff are responsible for 6,800 miles of in-city water mains, 109,000 fire hydrants, 148,000 catch basins (also called “storm sewers”), and 7,500 miles of in-city sewers. To prepare for a storm like Henri, they activate the Flash Flood Emergency and Coastal Storm plans. Under these plans, crews:

• pre-inspect hundreds of flood prone locations across the five boroughs before the storm to ensure catch basins are clear and functioning properly
• lower the storage levels in our bluebelt wetlands as well as ensure nearby culverts are clear of debris to maximize stormwater retention
• address flooding and sewer backup conditions during the storm
• pump out stormwater from low-lying roadways after the storm passes

An NYC sewer manhole on a rainy day

Wastewater Treatment

Our wastewater treatment staff treat more than 1 BILLION gallons of wastewater on a typical day. They operate and maintain 14 in-city wastewater resource recovery facilities, 96 pump stations, 426 combined sewer outfalls, four combined sewer overflow facilities, and an array of marine vessels. Storms like Henri trigger these staff to:

• conduct inspections of pump stations and Wastewater Resource Recovery Facilities to ensure that several days of needed treatment chemicals are available
• pre-position essential staff before the storm in case of transportation interruptions
• make contingency plans for potential power loss at plants and pump stations
• perform additional inspections of the most severely impacted pump stations during the storm and remove screening to prevent flooding of upstream sewers and streets
• respond to telemetry alarms and power disturbances due to the high flows from the torrential rains

Our operations staff do tremendous work to keep our essential services running 24/7, 365 days a year, rain or shine. Although service disruptions can happen on occasion, their rarity highlights the incredible work that takes place every day—under all sorts of circumstances—so that we can continue to turn on the tap and flush the toilet.