It was symbolic of the swath of destruction Hurricane Sandy brought to the Northeast on October 29, 2012: A roller coaster ends up half-submerged in the Atlantic Ocean.
The submerged portions speak of the widespread damage caused by the weather event. The part not submerged begged the question of whether it is possible to rebuild and emerge even stronger, much as many areas of south Florida did with new codes and infrastructure following the devastation of Hurricane Andrew in 1992.
Other issues of concern: How was stormwater infrastructure impacted? What toxins are still present in the region’s water bodies? Going forward, it is possible to “stormproof” an area, especially a coastal region? And given the cost, is it doable?
As of the start of 2013, municipal officials were still assessing the damage that Hurricane Sandy brought to the area’s stormwater infrastructure in late October 2012. Many still did not have a handle on the total impact from the storm, though a few numbers may provide some clues.
The estimated storm surge in New York, for example, was approximately 14 feet.
The website of the Federal Emergency Management Agency (FEMA) indicates that as of January 7, the agency had deployed 4,451 of its personnel for search and rescue, situational awareness, communications, and logistical support in states affected by the storm. Community relations teams were going door-to-door in the hardest-hit areas to inform survivors about available services and resources and to gather situational awareness. Housing inspectors were meeting with homeowners to identify damages to homes. The federal agency had so far approved $1.16 billion in assistance, with nearly 522,000 assistance registrations.
In New Jersey, the assessment of stormwater systems was still being conducted at the end of 2012, notes Abbie Tang-Smith, communications associate for the New Jersey Department of Environmental Protection.
“Emergent issues of safety, housing, power, natural gas supplies, water and sewer availability, and debris collection all had to be dealt with before assessment of the stormwater systems,” she says. Nonetheless, those within the agency believe the impacts to be similar to those to the sanitary sewer lines.
“Systems are sand-filled and compromised in many locations and not functioning as designed,” points out Tang-Smith. “Until assessments with cleaning and inspections are performed, we will not have an idea of the overall impact of these systems.”
Stormwater best management practices (BMPs) are generally designed to address flows that occur during a 100-year flood event in non-tidal areas and are not designed for a Hurricane Sandy-type of event, she says.
“As municipalities move from higher-priority infrastructure issues to stormwater, we expect to have more information regarding the performance of these systems,” says Tang-Smith.
State regulations require that wastewater pumping stations be protected against flooding and that adequate provision be made for access to the stations during storm events; wastewater treatment plants must also be raised above the flood elevation level or adequately flood-proofed, she adds.
“For the purposes of this requirement, the flood elevation level is considered to be one foot above the 100-year-flood elevation for non-delineated waterways and up to the flood hazard design flood elevation for delineated waterways,” she says.
Hurricane Sandy tested the infrastructure the Northeast has in place, and in the aftermath revealed its weaknesses and needs going forward.
Response and Resources
According to Mary Mears, a spokeswoman for EPA, wastewater treatment plants in coastal areas across New York and New Jersey were left damaged or without power in the aftermath of Hurricane Sandy. The treatment plant failures allowed untreated or partially treated wastewater to enter local waters.
EPA worked with the FEMA and the states to identify affected facilities and assess their damage and access to power, with the priority being to get the facilities operational as soon as possible.
In addition to assessing various wastewater and drinking water treatment facilities in New York and New Jersey, EPA provided technical assistance in addressing problems identified at Middlesex County Utilities Authority and the Passaic Valley Sewage Commission facilities. In response to requests from the New York State Department of Environmental Conservation (NYSDEC) and municipalities, EPA also provided assistance in assessing drinking water and wastewater facilities across the state. By the end of November 2012, EPA had assessed 40 drinking water facilities and 12 wastewater treatment plants. No further assistance was required after that.
The wastewater treatment plants in the state of New York that suffered the most damage were Bay Park (Nassau County), Rockaway (Queens County), and Yonkers Joint Wastewater Treatment Plant (Westchester County). Ocean Beach (Fire Island, Suffolk County) was also impacted.
Also according to NYSDEC, two other plants in Westchester (Yorktown Heights and Port Chester) were not fully operational until power was restored. Some of the affected facilities began disinfection as a temporary measure using pre-chlorination (adding chlorine) to the wastewater.
The effects from the discharge of partially treated or untreated sewage into waterways varied depending on local conditions, such as the extent to which natural flushing occurs from high flows–for example, in the Hudson River–or mixing in largely uncontaminated water, such as from the Atlantic Ocean.
In response to requests from the New Jersey Department of Environmental Protection (NJDEP) and municipalities, EPA provided assistance in assessing drinking water and wastewater facilities across the state.
EPA had assessed 40 drinking water facilities and 23 wastewater treatment plants by the end of November. Although no drinking water facilities requested EPA assistance, two wastewater treatment plants requested further EPA assistance: the Passaic Valley Sewerage Commission in Newark, NJ, and the Middlesex County Utility Authority in Sayreville, NJ.
The Passaic Valley Sewerage Commission receives sewage and industrial waste from 48 municipalities in and around Newark and is the nation’s fifth-largest wastewater treatment plant. During the storm, the plant was flooded and lost electricity until power was restored on October 31. EPA worked with state and federal agencies to remove wastewater from the plant and find environmentally safe solutions for sludge disposal until the plant was back in full operation.
During Hurricane Sandy, the Middlesex County Utility Authority lost power to its water utility intake pump until November 6 when power was restored. EPA worked with the utility and the state to fix damaged equipment.
“Since the beginning of the response by local state and federal agencies, significant improvements have been made in the operational status of many wastewater and drinking water plants,” says Mears, adding that EPA continued its support of the NJDEP and NYSDEC in the continuing recovery efforts.
EPA has numerous resources and programs to help drinking water and wastewater utilities prepare for and respond to emergencies, says Mears. EPA’s website provides a list of suggested pre- and post-hurricane activities for drinking water and wastewater facilities at water.epa.gov/infrastructure/watersecurity/emergencyinfo/pre-hurricane.cfm. (See additional content for a synopsis).
Prior to Hurricane Sandy, an intrastate network of water utilities that share resources with one another during emergencies, which EPA helps support, was activated, says Mears.
“During and after the storm, the network helped fulfill requests from utilities in New Jersey, New York, and Pennsylvania for generators and pumps,” she adds.
A Water and Wastewater Agency Response Network (WARN) is an intrastate network of “utilities helping utilities” respond to and recover from emergencies by sharing resources with one another. Included in the WARN framework are emergency contacts, expedited access to specialized resources, and training on resource exchange during an emergency. The American Water Works Association’s white paper, “Utilities Helping Utilities: An Action Plan for Mutual Aid and Assistance Networks for Water and Wastewater Utilities,” helps utilities develop a successful WARN.
The WARN includes a standardized Mutual Aid and Assistance Agreement, outlining the terms through which utilities provide resources to one another. It addresses indemnification, Workers Compensation, and reimbursement. Advanced agreements expedite resource sharing between utilities during emergencies.
Shortly before Hurricane Sandy, EPA released a Web-based tool for water utilities providing information on how they can identify federal funding sources to recover from emergencies and had shared that tool with utilities and stakeholders across the country.
The Federal Funding for Utilities–Water/Wastewater–in National Disasters (Fed FUNDS) tool can be found at water.epa.gov/infrastructure/watersecurity/funding/fedfunds/index.cfm and provides information on federal funding assistance before, during, and after a disaster.
Additionally, EPA provides technical tools for water utilities and communities to share and coordinate strategies and best management practices to prepare for utility service interruptions. More information on this effort can be found at water.epa.gov/infrastructure/watersecurity/communities/index.cfm.
EPA also has developed several guidance documents for utilities to prepare for emergency situations. The Guide for Evaluating Capacity, Management, Operation, and Maintenance (CMOM) Programs at Sanitary Sewer Collection Systems can be found at www.epa.gov/npdes/pubs/cmom_guide_for_collection_systems.pdf. Standard operation procedures for emergency collection system activities can be found at www.epa.gov/npdes/pubs/sso_optimizing_appc.pdf.
Green Infrastructure and CSOs
When Hurricane Sandy barreled through, New York City was in the midst of addressing its significant combined sewer overflows (CSOs). Some 70% of stormwater in New York City–including sanitary and industrial wastewater, rainwater, and street runoff–flows through combined sewer systems and is conveyed to the city’s treatment plants, according to New York City Department of Environmental Protection (NYCDEP).
In some city neighborhoods, sanitary waste and stormwater runoff are handled in separate sewer systems, with sanitary waste conveyed to wastewater treatment plants and stormwater channeled directly to local streams, rivers, and bays. Some areas such as parks and wetlands absorb stormwater into the ground or channel it into waterways.
In 2005, the NYC Department of Design and Construction published High Performance Infrastructure Guidelines, an internationally recognized green building reference for roadway and underground infrastructure. The Mayor’s Office of Environmental Coordination and the Design Trust for Public Space produced Sustainable New York City, a document using case studies to demonstrate the value of adopting environmentally sustainable practices into daily municipal operations. And in September 2010, the NYCDEP released its NYC Green Infrastructure Plan to integrate green infrastructure into its efforts to combat CSOs.
Two years prior to that, a local law was introduced to amend the city’s administrative code relation to developing and implementing a sustainable stormwater management plan, which was done by the Mayor’s Interagency BMP Task Force in December. Green infrastructure pilot projects ensued.
Additionally, long-term control plans, required by EPA for cities with CSOs, address New York City water bodies and their drainage basins and outline a comprehensive plan for each, which are in various stages of approval.
An organization that advocates for green infrastructure to ensure swimmable and fishable waters around New York City is Stormwater Infrastructure Matters (SWIM) Coalition, sponsored by the New York City Soil and Water Conservation District. SWIM points out that each time it rains, large volumes of stormwater inundate New York City sewers, causing 27 billion gallons of raw sewage and polluted stormwater to be discharged each year into local waterways through CSOs. After a heavy rain or snowmelt, overloaded sewage treatment plants are designed to divert the combined untreated wastewater to the nearest creek, river, or bay via CSO structures.
SWIM advocates for the cooperative effort of public and private agencies to establish means of capturing stormwater on land through green infrastructure, indicating that widespread on-land stormwater management can make it possible for New York City waters to meet the Clean Water Act standards for safe swimming and fishing, while meeting local sustainability goals that include creating more green open space. Its mission is to affect change through policy, implementation and outreach, education, and monitoring. SWIM advocates sustainable stormwater management methods such as urban forestry, wetland management, green roofs, permeable pavement, rainwater harvesting, rain gardens, community gardens, composting and soil remediation, and shellfish restoration (oysters, for example, also act as water filters).
In a posting on its website, SWIM indicates that the 14-foot storm surge that Hurricane Sandy brought to some places along the coastline and other low-lying areas may have signaled to New York City, state, and local leaders that it’s time to “think more seriously about measures to protect the city from another storm of this magnitude.
“Engineers, architects, planners, scientists, and citizen groups have all agreed for a while now that something needs to be done to make the city more resilient but up until this point there has been a lack of urgency to take action. Hopefully, this is changing,” points out SWIM.
In an article in the New York Times appearing on November 3 and 4, 2012, in the Web and print editions, Governor Andrew Cuomo–who acknowledged that climate change is a “reality”–supported the idea of a sea wall, noting that the recent history of significant storms hitting the area call for elected officials to consider new and innovative plans to prevent similar future damage.
While New York City Mayor Michael Bloomberg agrees the hurricane is a call to more action, he disagrees an expensive sea wall is the answer, saying he didn’t believe the city would get value for the price tag it would require–upward of $6 billion.
Many architects, environmentalists, and civil engineers agree that in addition to being expensive, large-scale projects like underwater gates are unwieldy and difficult to build and may not necessary work, according to the New York Times article.
Actions being proposed in New York include building code alterations (such was the reaction in other hard-hit areas of the country following devastating hurricanes), banning the housing of boilers and electrical systems in basements, and a measure that doesn’t always bode well with people who love the water and spend more money to live near it–moving inland.
It’s called “managed retreat” and is an option being discussed by those the like of Radley Horton, associate research scientist at Columbia University’s Earth Institute and a climatologist at the NASA Goddard Institute for Space Studies. He also has served as the climate science lead for the NYC Panel on Climate Change.
He has told media outlets such as National Public Radio that there are some areas where soils may not support hard infrastructure, and that needs to be part of a discussion on solutions.
Jason Monnell, a research assistant professor in the Swanson School of Engineering in the Civil and Environmental Engineering Department at the University of Pittsburgh, points out there are many lessons learned from Hurricane Sandy.
“The facts are that more severe storms have seemingly been observed over the last 20 to 30 years, and during that, people have to plan accordingly,” he says in reference to climate change.
Yet planning for such weather events necessitates spending a significant amount of money. Case in point: burying utility infrastructure such as telephone and utility wires.
“There’s not a lot of willpower to do that from the taxpayer or utility basis. That has to change if you want to stormproof that,” says Monnell. “These are national choices that are not being made, and instead of being ballot measures, they are being voted more by the pocketbooks.”
Monnell says the overall lesson is the nation’s aging infrastructure needs to be a national agenda. “It needs to be addressed by lawmakers and policymakers to figure out what’s the best way to move forward.”
That may include moving parts of cities inland or creating a more robust infrastructure.
“These are things that are tough to address because they are billion-dollar problems,” points out Monnell. “It’s hard to recover from such events, but if you live in a coastal area, the choice of being there comes with those kind of dangers.”
Contemporary stormwater infrastructure is set up to handle smaller storms, even an occasional 100-year storm. Yet the more significant weather events in recent years exceed most of that planning, says Monnell.
“It’s hard to prepare outside of emergency tactics,” he says.
More green infrastructure and other soft measures may help augment tradition hard or “grey” stormwater infrastructure–but only to a point, Monnell says.
At the University of Pittsburgh, Monnell and his team recently conducted a study on green roofs and how they compare to control roofs on the same structure and same surface area. “We determined that green roofs can absorb a certain amount of additional water, up to half an inch to an inch, depending on the weather conditions before that,” says Monnell. “That is very good for the day-to-day average rainfall and mitigating the sudden burst of stormwater.”
The challenge comes with a large storm that is typically preceded by a small amount of precipitation, which would saturate the green roof and could potentially even lead to erosion.
“If it was saturated to its capacity, then it would discharge to the storm sewers as it would before or if you did not have that green roof,” says Monnell.
Ultimately, a green roof serves as an effective buffer for most day-to-day weather and can be a “really good planning piece” for most municipalities to reduce stormwater treatment, says Monnell.
During Hurricane Sandy, Pittsburgh got up to three inches of rain, of which a green roof may have been able to handle a half-inch, Monnell says.
“Everything else would have overflown into the storm sewers in Pittsburgh and then into the rivers,” he adds.
Franco Montalto is a professor in the Civil, Architectural, and Environmental Engineering Department and the director of the Sustainable Water Resource Engineering Lab of Drexel University in Philadelphia, PA. He has a background in the design and monitoring of green infrastructure and stormwater mitigation and operates a consulting practice in environmental engineering, eDesign Dynamics, in New York City. Montalto was expected to testify in January at a New York State Assembly hearing on post-Hurricane Sandy adaptation strategies.
The New York City native has been studying such strategies as a member of the Consortium for Climate Risk in the Urban Northeast (CCRUN). The five-year effort is funded by the Regional Integrated Sciences Assessment (RISA) program of the National Oceanic and Atmospheric Administration (NOAA).
CCRUN is a collaboration of universities studying the effects of climate change on the urban Northeast, particularly in Philadelphia, New York, and Boston. CCRUN is one of several groups of researchers in regions nationwide studying region-specific climate-related issues. Researchers include climate scientists, water resource engineers, and public health representatives.
Montalto is focusing his efforts on green infrastructure as a climate change adaptation strategy. “We’ve got studies that involve looking at the effects of changes in precipitation intensity on runoff, the extent to which evapotranspiration can be promoted in urban spaces by adding greenery and comparing the different types of green spaces–green roofs and green streets, for example,” he says. “In all of that, we try to relate to ecological baseline conditions.”
The group has current research going on in one of the last old growth forests in New York City–Alley Pond Park–that is used as an ecological reference.
Hurricane Sandy–and Irene before that–provided preliminary data on green infrastructure’s role in stormwater management.
“Sandy was very difficult to monitor,” points out Montalto.
He had sensors placed in a half-dozen highly instrumented sites where a range of parameters are being monitored. Because the havoc wreaked by Irene in August 2011, the team had removed many sensors so they wouldn’t get destroyed.
“We left some up and were able to do some estimations,” says Montalto. “Sandy was a climate event characterized by extreme wind and storm surges. It wasn’t as much of a rain event as Irene had been. Looking at some of our sites, we were able to measure between 1 and 1.5 inches of rain in New York City and how much of that rain in these newly engineered green spaces were able to send into the ground versus how much runoff.”
Preliminary results came in from a green street in Queens. The street is one of “thousands” of vegetated depressions constructed by the New York City Department of Parks and Recreation.
“Most of them were built for horticultural and aesthetic purposes and not necessarily designed for stormwater management, though in the last few years as New York City has moved to a green infrastructure as a means of addressing its CSO problem the parks department has revised its design strategies and incorporated stormwater management,” says Montalto. “We have worked in partnership with them for the last four years. I’ve gotten funding from a variety of sources to instrument some of these stormwater-capture green streets.”
The Queens location–located at the corner of Nashville and 116th Avenue–offered the best post-Sandy data. Stormwater originating from the street and sidewalk is directed through a curb cut that goes into a vegetated depression. When the vegetated depression gets saturated and overflows, the overflow goes into the sewer.
CCRUN has water level loggers inside of the depression. “We have a flume so we know exactly how much water is coming in and a full climate station onsite so we know exactly how much rain fell in that area,” says Montalto. “We have other sensors such as soil moisture sensors there, so we have a section of the vegetation on a very sensitive scale.”
By observing changes in the mass of the monolith of soil and vegetation, the CCRUN teams knows that if the mass is going up, the monolith has gotten wetter, and if the mass is going down, the mass has gotten drier either through evaporation or infiltrations.
Using that suite of instruments, the CCRUN team observed that because of the high wind or the degree of debris spread on the street–Montalto says he can’t be certain–the amount of water that came into the green street during Hurricane Sandy was 10 times what would have been expected based on topography.
“If I take 1.3 inches, which at that site was how much registered precipitation we had, and multiply it by the contributing area to this green street and compare that volume to the volume of water that actually came in, we got 10 times more water coming in than was just rain falling on that area,” says Montalto. “Essentially, there was water going all over the place, and a lot of it was coming into the green street. But then, based on the lysimeter measurements in the green street, we saw that there were successive waves of infiltration that happened during different periods of precipitation during the storm.”
That means the site was effectively sending water into the ground.
“We’re estimating up to about 10% of the water that came in was sent into the ground, so 10 times the amount of water that would ordinarily come in came in because of rain being blown into the catchment area and, I’d say, drains within adjacent areas being clogged due to debris in that water adding to what would ordinarily come in,” says Montalto. “Of that, 10 times as much, about 10% of it was infiltrated into the ground during and immediately after the storm.”
What the team observed after Hurricane Irene at some of the sites was a peak in the amount of evaporation that occurred.
“Irene was a real saturating event, so a lot of our sites got really wet,” says Montalto. “They were ponded and saturated, and it happened in the summertime when the limit on evaporation in the summer is not the atmosphere; the atmosphere wants to suck the water out of the ground. It’s the fact that the moisture is not in the soil. You can’t evapotranspire at the potential rate that the atmosphere would allow you to.”
But during a saturating event during the summer, an area can get significantly high amounts of evaporation.
“Immediately after, these systems will compensate by evaporating at nearly potential rates, meaning nearly the rates that are physically possible given the local meteorological conditions,” points out Montalto.
The Queens site was able to deal with a lot of water that came in, Montalto says. “The site is built in an area with high-permeability soils, and you’re not going to get the same level of performance in places where you build green streets on soils that are not as highly permeable.”
The message is clear, he says. “As we think about adaptation strategies or protective measures from more extreme climate events, we need to invest the money in multi-functional solutions. In this particular region, if you look at what climate scientists tell us, the range of extreme climate conditions that we could experience spans the gamut from Irene to Sandy to other things. We could have prolonged drought. We could have intense precipitation. We could have altered timing of precipitation. We could have elevated temperatures.”
What is needed is an urban ecosystem that can buffer against a variety of these types of conditions, he adds.
“Vegetative strategies make a lot of sense because they can remove heat, infiltrate water, and they can pond water, and that’s a different set of strategies,” says Montalto. “I’m not saying that in some places there isn’t a need for investment in hard infrastructure. Take the hard infrastructure strategy to an extreme and imagine you have an urban area with low ecosystem service value–it gets really hot, and it doesn’t have any vegetation to mitigate that heat and when it rains; it’s so impermeable that all of the water just ponds, runs off, and creates problems.
“If you protect this low-performing ecosystem with a big wall, is that as valuable as increasing the ecosystem service value that can be provided all of the time, not just in one particular type of extreme event?”
Measuring Pollutants
With stormwater runoff comes the flow of pollutants and toxins. Following Hurricane Katrina in 2005, problems emerged with hazardous and toxic materials and sewage being released or carried in the floodwaters. Hurricane Sandy was no different.
In New Jersey, the DEP contacted industries permitted to discharge into the largest sewage treatment plants that were impaired by the storm seeking flow reductions and, where possible, temporary termination of flows in an effort to minimize impacts to the environment, human health and safety, and receiving wastewater treatment plants, notes Tang-Smith.
EPA has coordinated efforts with FEMA and state, tribal, and local governments to address any potential threats to human health and the environment–including potential releases of contaminants, damage to waste and drinking water infrastructure, and potentially contaminated debris–that have arisen as a result of Hurricane Sandy, says Mears of EPA.
In the aftermath of Hurricane Sandy, EPA sampled various water bodies. Water samples were collected in Newark Bay and New York Harbor at the request of the NJDEP to determine concentrations of bacteria from the releases of raw or partially treated sewage from the storm-damaged Passaic Valley Sewerage Authority.
All 10 samples taken exceeded the New Jersey established limit for fecal coliform of 14 colony forming units (CFU) per 100 milliliters of water for shellfish harvesting. EPA advised people to avoid activities that could bring them into direct contact with the waters in Newark Bay and New York Harbor.
EPA also collected water samples in the Hudson River in the area surrounding the Westchester-Yonkers Joint Wastewater Treatment Plant outfall to determine concentrations of bacteria and dissolved oxygen from releases of raw or partially treated sewage from the storm-damaged sewage treatment system in Westchester County.
The samples were analyzed for fecal coliform and dissolved oxygen. The established limit in New York is 200 CFU per 100 milliliters of water for secondary contact such as boating and fishing. The fecal coliform level of one EPA sample was above the limit. EPA also advised people to avoid activities that could bring them into contact with the waters in and around the Westchester-Yonkers treatment plant. Levels of dissolved oxygen were above 5 milligrams per liter, which is generally accepted as being protective of estuarine life.
EPA collected water samples in the East Rockaway, Hog Island, and Reynolds channels adjacent to Island Park and Long Beach, NY, analyzing them to determine concentrations of bacteria.