by the Atlantic Chapter Hudson River Committee
In September 2022, the U.S. Army Corps of Engineers, the federal group that handles large flood risk management and other projects across the country, put out a new report on flood control measures in and around New York City. This report lays out a proposed plan to protect the people, environment, and infrastructure of the region from future storms, created as part of the New York-New Jersey Harbor and Tributaries (NYNJHAT) Coastal Storm Risk Management Feasibility Study. The plan is critically important to the region, but is as of yet tentative. As such, there is still time to shape the final version and advocate for communities and the environment in the plan - the public comment period for this phase ends March 7th. Here is what you need to know in order to understand what is on the table and start your comments:
What is this study about?
After Hurricane Sandy devastated the region in October 2012, the Army Corps commenced the North Atlantic Coast Comprehensive Study to evaluate flood risk in areas impacted by the storm. In the years to follow, the Corps identified the New York-New Jersey area as a key one on which to focus. The Corps then undertook a subsequent study to evaluate potential risk-reduction measures in this area. In 2019, the Army Corps put out a set of alternative plans, essentially models of what flood protections - like sea walls, flood gates, levees, etc. - could look like in the area in the coming decades in order to alleviate flood risk in the future. This is particularly important as climate change makes the incidence of floods and their severity grow over time. New York City, for example, could see as much as 50 inches of sea-level rise by the end of the century compared to a 2000-2004 baseline under only moderate projections. With more than eight million people in the City alone, this poses grave threats to safety, wellbeing, and economies. The impacts to the natural environment, yes even in the concrete jungle, are also myriad and paramount.
The menu of alternative plans ran the gamut from a several-mile closeable flood gate barring up the Hudson estuary from Sandy Hook, NJ to Breezy Point, NY, to solely on-shore measures. The Army Corps has now tentatively selected a middle-ground plan, their number “3B,” based on a cost-benefit analysis and is seeking feedback on this.
Essentially, the people along New York’s coasts are now facing the tenth year of flood risk measures studies, without a comprehensive flood risk management plan in place from the Army Corps. Part of this was due to a hiatus taken during the Covid-19 pandemic’s height, as well as the time requirements for a technical study of this kind. However, time is of the essence, as storms worsen and communities remain unprotected. The next step is for a proposed plan to get finalized (after the public comment period and reworking) and then move forward into the approvals and appropriations process, until eventually design and construction can begin. Even once the lengthy planning process is over, it is important to note that 3B has a first cost of $52.6 billion price tag and wouldn’t be scheduled to be finished - without accounting for possible delays and overshoot - by 2044.
What is proposed in the new report?
The Army Corps’ “Tentatively Selected Plan,” option 3B, is one that balances both in-water and on-land measures. These are mostly engineered hardscapes, with notes throughout the September report that they will consider nature-based add-ons to the plan in a later phase. Furthermore, it is important to note that the Army Corps has tentatively selected a plan from the menu of options they themselves created. Is the entree a good option in general? Or is it only the best option from a limited menu? These questions make a big difference when determining if residents want to take a bite.
Not all areas that are subject to flooding will be protected and not all risk can be managed. Storms move and deposit water to varying degrees and directions, which can be complicated by tidal dynamics and other factors. Nothing will provide a perfect bubble of protection. However, it is important to ensure that environmental justice areas (low-income and/or minority) and others with particularly vulnerable populations are covered sufficiently by protection measures. While the Army Corps analysis did examine environmental justice, it is important to note that flood barriers may not always be the right answer everywhere - protection can take the form of relocation, floodproofing (though this is limited if communal infrastructure is compromised), and other methods. Oftentimes a combination of approaches is itself the most resilient.
With regard to hardscape, built infrastructure, there are two important drawbacks to consider. The first is about built-in rigidity. Nature-based systems are largely flexible and adaptive (e.g. they grow) over time and can absorb shock without “breaking,” whereas engineered hardscape measures - like conventional sea walls and flood gates - do not. These concepts about the benefits of natural elements in flood protections come from Army Corps guidance itself, put out by the Engineering With Nature sub-group. However, despite the awareness of the importance of integrating natural measures, these are postponed to a later phase of the study for this project. This represents a large gap in the planning of all the menu of alternative plans, as well as the selection of the 3B entree.
The second drawback concerns the importance of a system-wide approach to management. Nature-based solutions may provide co-benefits not examined for hardscapes, such as habitat value, heat mitigation, and others. Additionally, hardscapes can have negative consequences on ecosystems and, while the Army Corps study does begin to evaluate this via their mandated Environmental Impact Statement process, it does not necessarily show the complicated dynamics of the river system as a whole and the possible negative side effects of the plan, which may include the further removal of wetlands and other beneficial elements. None of the proposed plans use a nature-first approach. It is likely that nature-only solutions may not be able to handle the amount of flood risk in all proposed locations sufficiently in a dense area like New York City. However, plans that integrate nature and human-made features from the start are advisable in many cases. Similarly, the barriers that are proposed are often open for small-scale weather events and closed for larger ones - addressing the small and medium storms is important, especially if hard-engineered elements may remain mostly dormant. The same is true regarding ongoing sea-level rise that will occur even in the absence of storms, and flooding inland from rain events. The current proposed plan does not target protection from these events. It also fails to address the fact that gates may need to be closed frequently due to sea-level rise in the future, posing more threats to our waterways.
The Hudson River, or the Mahicantuck, is a mercurial sort of waterbody. Being a tidal estuary, where oceanic saltwater mixes with freshwater, it ebbs and flows and rises and falls. These properties make it incredibly important to wildlife and natural habitat, such as the more than 200 fish species that call the Hudson estuary ecosystem home. The effects are far-reaching on the human species as well - with over 13,400 square miles of watershed area, more than 14 million people live in the adjoining counties. Notably, the measures in 3B, and the whole menu of alternatives, focus on New York City (and parts of New Jersey), while leaving out other key areas up the Hudson that face risk.
What do I do in the comments?
Think about what is important to you and affects your life and the life of your community. Keep in mind that New York City and the region need flood protections sooner rather than later, but that these may take on different forms. Put these into words and think about how the proposal, 3B, does address these or does not - use the materials, such as the recorded public meeting videos on the Army Corps website to inform your opinions. You can also access videos from experts and a workshop recording on how to write effective comments from Rebuild by Design. Send your thoughts and concerns to the Army Corps before March 7th. You can easily take action by sending the Sierra Club's comments here.