RAMAPO WEIR REPAIR
An important part of TU’s mission is the restoration of our waterways.
There has been a weir on the Ramapo River for an indeterminable amount of time. Sixty years ago, it stretched straight across the river creating a deep pool on the west side of the river. Over the years it had collapse into a downstream facing “U” shaped configuration which resulted in more and more water being pushed towards the banks. Continued erosion caused the river to widen and become shallower. Water temperature increased in summer and trees along the banks were undermined.
After several years of planning and communicating with State and County agencies, we determined that if our efforts were limited to the relocation of materials already in the river and if work was limited to manual labor and hand tools, we could proceed. The weir was breached and boulders were relocated to create two upstream facing cross vanes. Cross vanes are stone structures which start at the riverbank and gradually diminish in height and width until reaching an endpoint near midstream.
Cross vanes direct the water flow towards the center of a river. In addition, eroded banks were reinforced by placing stones to deflect and slow the force of the water. It took many hands and a full day of work in the river to accomplish the task. Several local residents joined in along with a local environmental group.
Further observation showed that although the main flow was now directed to the center of the river and pools formed by years of erosion were filling in with sand and silt, some adjustment was needed. We were able to improve the area further in a few hours with the help of a dozen EJTU members.
We will continue to monitor the conditions in this area of the river. If appropriate, additional adjustments will be made.