Activists say a fast-tracked yet somewhat secret plan threatens the "existence of the Hudson as a living river."

In response to Superstorm Sandy, the U.S. Army Corps is considering six different plans to explore the impact of offshore barriers, land-based floodwalls and the potential of a levee system for the Hudson River.

According to Riverkeeper, the six plans involve massive in-water barriers and/or land-based floodwalls, dunes and levees intended to “manage the risk of coastal storm damage” to New York Harbor and the Hudson Valley.

"Anyone who cares about the Hudson River needs to become informed and involved, now. Several of these plans – specifically, the ones including giant in-water barriers throughout New York Harbor – would threaten the very existence of the Hudson as a living river," Riverkeeper wrote.

The organization claims that everyone who lives near the Hudson River, from New York City to Troy, including here in the Hudson Valley, will be impacted by the U.S. Army Corps plan.

"We all know that sea level rise and more frequent, intense storms require action and planning," Riverkeeper said. "But there is a difference between creating more protective, resilient shorelines over time, and installing massive, in-water barriers that threaten to change the ecosystem forever. Offshore barriers will choke off tidal flow and fish migration – the very life of our river."

The purpose of the New York – New Jersey Harbor and Tributaries (NYNJHAT) Coastal Storm Risk Management Feasibility Study is to manage the risk of coastal storm damage in New York and New Jersey "while contributing to the resilience of communities, critical infrastructure, and the environment."

The U.S. Army Corps is hosting a number of meetings in New York and New Jersey to discuss their plans.

The only meeting in the Hudson Valley is scheduled for Wednesday, July 11, from 6-8 p.m. in Poughkeepsie at the Hudson Valley Community Center located on 110 South Grand Avenue.

"This process is being fast-tracked, and it’s an outrage. The Army Corps gave only 12 days’ notice for meetings on an issue that will take many years to resolve and could change the river forever," Riverkeeper said.

New York State Senator Terrance Murphy called for more meetings to be scheduled in the Hudson Valley, mainly Rockland and Westchester counties.

"The federal government has invested hundreds of millions of dollars in other estuaries along the East Coast," Murphy said in a press release. "While the Hudson River has been consistently overlooked, this is a great opportunity to work together to find viable solutions to address its many needs. However, our region must have a seat at the table for these conversations."