Round Valley Reservoir Project
(updated 10/27/22)


Round Valley Reservoir Project Update: 10/27/22

NJWSA Update: 8/3/2022

Township’s letter to the NJ Water Supply Authority: 7/21/22

Additional Information Released by the NJ Water Supply Authority on 7/14/22  

A site-specific study was performed under a collaboration of New Jersey Department of Environmental Protection Bureau of Dam Safety, the Department of Homeland Security, and the US Army Corps of Engineers which recommended consideration of restriction of vehicular access to the Dike.  The structure in this case is the Round Valley Dike which County Route 629 crosses. The Dike is one of three dams that impound the Round Valley Reservoir and is the only one of the three that permits unrestricted vehicular access.  Due to security concerns, we cannot share the specifics of the study in a public forum.

NJ Water Supply Authority's July 6, 2022 Statement

As you probably already know, County Road 629 in Clinton Township, Hunterdon County has been closed since April 8, 2020, from the corner of Cherry Street and Old Mountain Road to just east of the driveway to the NJDEP “fishlabs”.  The fish labs are located just east of the parking lot access to the Round Valley Fish and Wildlife Boat Ramp. This was originally proposed as a temporary closure during the construction project on the Round Valley embankments.  This temporary closing was allowed by Hunterdon County Engineering at the request of the New Jersey Water Supply Authority (Authority).

Recently, the Authority has had informal conversations with the Hunterdon County Engineering Department, the Borough of Lebanon, and Clinton Township about making the existing temporary closure of County Road 629permanent.  Following our informal discussions, a specific request to close the road permanently has been asked of the mayors of Lebanon Borough and Clinton Township in advance of a formal similar request to Hunterdon County. If the closing is allowed, it is our intent, after all construction is complete, to continue to allow public access on the road for pedestrians and bicycles only.  Keys to the vehicular access gates would be provided to Lebanon Borough, Clinton Township, and Hunterdon County emergency staff for vehicular access. This is not out of the ordinary as keys have already been provided to the same emergency services groups for to access other Authority-owned secure areas.

The purpose of this change is to improve dam safety. We cannot share specifics, but I can tell you that a very serious threat to earthen dams by bad actors would be facilitated by vehicular access to the structure.  County Road 629 is the crest of the Round Valley Dike.  Be aware that failure of any of the three Round Valley dams would have catastrophic impacts on downstream residents and water supply to over one million people in central New Jersey. It is also noted that the Authority has received verbal support of this proposal from New Jersey Department of Environmental Protection’s Bureau of Dam Safety.  The Round Valley Dike is the only one of the three embankments (at Round Valley) with unrestricted vehicular access to the crest. To my knowledge, there are no earthen embankments of this size in the state of New Jersey that allows public vehicular access.

I hope this helps you understand the situation. We do plan to add this information along with updates to our website in the future. The link to our project-specific webpage follows.

Round Valley (