Six proposals are on the table to protect New York City and its surroundings from catastrophic flooding, including two plans to separate the city’s harbor — and therefore the Hudson River — from the Atlantic Ocean with a combination of seawalls and gated storm surge barriers.
Hudson River environmental groups have attacked these two plans, with one representative calling them “truly immoral” because of the potential effects the groups anticipate, including walling off the migrations of fish, limiting the flushing of pollutants from the New York City Harbor, and permanently altering the biology of the river.
These in-water barriers would not address sea level rise from climate change, the environmental groups stated.
The array of six proposals are a direct response to the destruction and death brought upon NYC by Superstorm Sandy in 2012 and could cost anywhere from a few billion to tens of billions of dollars, according to the U.S. Army Corps of Engineers (USACE), which is considering the proposals in a study with New York and New Jersey. The options will be pared down to one or two in a report to be released by late fall, according to the agency.
The environmental groups say insufficient information is being taken into consideration in paring down the six options, the timeline is too brief, and New Yorkers are not being engaged in the selection process.
Stopping Another Sandy
Superstorm Sandy struck the coasts of New York and New Jersey on Oct. 29, 2012.
At least 117 Americans died from the storm, including at least 53 in New York state, according to the U.S. Centers for Disease Control. Most of the New York deaths were in the city, but at least seven perished in the Hudson Valley, according to the New York Times.
To help prevent another Sandy, New York, New Jersey, NYC and the federal government began a study in July 2016 to examine the problem, according to the USACE, coming up with six proposals released this summer.
The six proposals vary widely in scope. The first option is to do nothing, though it is important to note numerous projects are already being undertaken by local governments to address catastrophic flooding after Sandy, and this option simply means a federal-state-municipal flooding plan would not go forward.
The other five options include a variety of in-water and shoreline barriers. The first two would separate the Hudson from the Atlantic with barriers whose gates would be raised in storm conditions and are the options most concerning the environmental groups.
The second option involves an in-water storm surge barrier stretching five miles from New Jersey to Queens, according to a USACE slideshow of the proposals. Miles-long levees or berms would be constructed along the Queens and New Jersey coasts connecting to this barrier. A smaller surge barrier would run between the Bronx and the northern coast of Queens in the Long Island Sound.
The third option involves five smaller in-water surge barriers, including one stretching from Staten Island to Queens, as well as several levee/berm systems, according to the slides.
The fourth option involves six smaller in-water surge barriers, as well as levee/berms and shoreline barriers, while the fifth option is a similar plan with five in-water surge barriers, according to the slides.
The final option involves no in-water barriers and proposes only shoreline barriers.
The in-water surge barriers would include gates allowing the passage of water except during storms, when the gates would close, according to the USACE, but it is not yet known how wide these gates would be.
The Hudson is called a “tidal river,” or, less flatteringly, a “drowned river,” because it is at sea level from where it meets the ocean to the Troy Dam, 160 miles north of New York City. This means the river flows towards the Atlantic when the ocean’s level dips during low tide, and away from the Atlantic during high tide. Salt water can be detected as far as 60 miles upriver.
Environmental groups worry the two options with barriers between the Hudson’s channels and the Atlantic would forever change the river — one representative called the potential consequences “catastrophic” — because water and the life in it would be unable to freely pass through. In a detailed response to questions from The Other Hudson Valley, USACE spokesman Michael T. Embrich addressed some of these concerns, writing that in-water barriers were generally designed to minimally impact water flow during non-storm conditions.
The in-water barriers currently under consideration would involve a combination of storm surge barriers and seawalls, Embrich wrote. The storm surge barriers would make up most of the structures and would include gates that would only close during storms. Seawalls, which do not have gates, would “generally only be used for tie-ins to land.”
“Generally surge barriers are designed to have as minimal impact to existing flows during ambient conditions as feasible.” Embrich wrote. “That being said, the [USACE] is preliminarily evaluating the possible effects to daily tidal flows (as well as storm event conditions) related to the various alternatives that involve storm surge barriers.”
Jeff Anzevino, the land use advocacy director for the Hudson Valley conservationist group Scenic Hudson, stressed the breadth of what would be affected by the two options with barriers between the Hudson and the Atlantic: the NYC Harbor, the Hudson River up to the Troy Dam, and the Harlem, Hackensack, East and Passaic rivers, among others.
“My gut reaction is to say that these could have devastating effects, but the reality is, we don’t really know,” he said. “Any in-river barrier has the potential for major effects, and significant adverse effects, but we don’t know how they’re going to be designed.”
Scenic Hudson knows the reality of future flooding and the need to mitigate the risk, Anzevino said.
“The question is, how are we going to manage that risk?” He said.
In a post by the Hudson River environmental group Riverkeeper, the group writes about what they see as the potential impacts of the in-water barriers.
“From Day One, these offshore barriers would start to restrict the tidal flow, contaminant and sediment transport, and migration of fish. They would impede the tidal “respiration” of the river. We fear that a slow death would be inflicted on the river, and that in time, the barriers would slowly, but surely, strangle the life out of the river as we know it,” according to the post.
The barriers would “significantly restrict” the migration of striped bass, Atlantic sturgeon, herring, shad, eel and other species, and would cause pollutants to back up in the New York City Harbor, causing algae blooms and altering the percentage of oxygen in the river, according to the post.
Riverkeeper also questions how the barriers would allow floodwater to drain from the river during Hudson Valley storms, such as Hurricanes Irene and Lee in 2011.
The barriers are designed to stop storm surges flooding NYC from the ocean, but the same system could arguably stop water from draining out to the ocean during upstate storms.
If a storm hit only upstate, the barrier’s gates would be open and would not affect the draining of rainfall into the ocean, according to Embrich, though these barriers would be closed if the storm also hit the coast.
Embrich called this situation “a significant design consideration.”
“Generally though, the discharge of the storm-produced rainfall in this watershed through the various tributaries occurs after the arrival of the storm surge into the estuary,” he wrote, arguing the lower Hudson would only crest after the storm had passed, by which time the barrier’s gates would theoretically have been re-opened.
The U.S. Army Corps of Engineers is under pressure to efficiently pare down the projects to one or two options due to a piece of legislation passed in 2014 putting monetary and time restrictions on USACE project feasibility studies.
The law introduced the “3-by-3-by-3” criterion to feasibility studies undertaken by the USACE. Since then, feasibility studies must be completed within three years, must cost no more than $3 million in federal dollars, and must be concurrently, as opposed to consecutively, reviewed by the three levels of USACE to speed along the process.
The USACE has requested the rules be relaxed for the project, and may ask for further leniency in the future, according to Embrich.
“Given the expansive geographic study area and complexity, we have already been approved to utilize up to $6 million” during the paring-down process, Embrich wrote, and the USACE may seek more time and funding after the paring-down process “based on feedback from other agencies, stakeholders and the public.”
However, regional politicians have pushed for more time before the options are whittled down to one or two, as well as more public engagement.
State Sen. Terrance Murphy, whose district includes parts of Westchester, Putnam and Dutchess counties, urged the USACE and the DEC to “hit the brakes” on the project, schedule more public meetings and to “make sure the public is guiding the discussion before they make any rash decisions that will have permanent effects.”
State Assemblywoman Didi Barrett, whose district includes areas on the Hudson’s east bank, urged for an extension of the Aug. 20 deadline for public comment, railing against the fast-tracking of federal studies and comparing the barriers to the now-rejected plan to establish 40 barge anchorage sites along the Hudson.
Hudson Valley Congressman John Faso said in a statement he was “concerned about the economic and environmental impacts this could have on the Hudson River and its fishery,” adding he was researching the issue further.
A Lack of Information
No original studies will be undertaken in paring down the options to one or two, with the USACE relying on existing data.
John Lipscomb, the vice-president for advocacy for the Hudson River environmental group Riverkeeper, said his organization welcomes the USACE study.
“However, we object to the process by which alternatives have been put forward without supporting studies,” he said. “The public is being asked to comment on – what?”
Riverkeeper is “scrambling” to figure out the specifics of the options “in the absence of data from the [USACE],” he said.
“We are on a crash course,” he added.
Though USACE will produce original studies on the environmental impacts of the plans after the paring-down process, according to Embrich, Lipscomb agreed this would be putting the cart before the horse and said it would be “a calamity” to only produce the studies after there are only one or two options left.
The New York Department of Environmental Conversation (DEC), a state sponsor in the process, responded to a list of questions about the project with a statement saying the protection of coastal communities is “a top priority” after Superstorm Sandy and anticipated sea level rise, and the agency is “committed to exploring all options as part of a comprehensive approach to bolstering coastal resilience and ensuring our communities and the environment are protected.”
New York could “pull the plug” on any of the options at any time, according to Lipscomb.
But, What About Climate Change?
The in-water barriers would do nothing to address sea-level rise, according to both Anzevino and Lipscomb.
Since the gates in the barrier would be open much of the time and climate change is a slow process (by human terms, anyway), any increases in sea level would simply be pushed past the barriers while they are open.
The barriers would address one of the effects of climate change — more frequent storm surges that would be more destructive since they will be rising out of a higher sea — but not the everyday encroachment of the ocean that will submerge the city’s shoreline neighborhoods in the next 100 years.
Since the Hudson River is at sea level up to the Troy Dam, sea level rise would affect the Hudson Valley at about the same rate as the world’s coasts.
Because of environmental issues the organization predicts from in-water barriers and how they fail to address many climate-change issues, Riverkeeper has endorsed the sixth option, the plan proposing only shoreline measures.
These measures would address sea- and river-level rise, holding back rising waters from encroaching on the land, according to Riverkeeper.
Lipscomb points out many shoreline measures are already being undertaken by local governments, and option five would continue these methods.
Additionally, the shoreline measures would be less costly and could be started quickly on a priority basis, whereas the New Jersey-to-Queens barrier may not be completed for 15 years and would do nothing to protect against storm surges until then, Lipscomb said.
“Kingston needs to protect itself now, not 15 years from now,” he added.
Lipscomb listed the ways mankind has altered the Hudson since the Industrial Revolution, including the filling-in of side channels and wetlands through dredging, the introduction of invasive species through canals, the blackening of the river through pollution, and the toxification of its waters by PCB dumps from the now-shuttered General Electric plants north of Albany.
“We are poised to turn around the past, we are poised to start a new epoch of healing if we can stop harming the river,” he said.
With regards to the project, “there’s stuff that’s got to be off the table, and barriers that restrict the tide in the Hudson should be off the table,” he added.
Public comments are being accepted until Aug. 20 and can be emailed to the USACE here. The DEC does not appear to have an official way of receiving comments about the project, but the Director of the Communications Office for the agency can be emailed at email@example.com.