Like the other weirs along the Old Croton, this structure, standing atop both the aqueduct and an intersecting stream,
provided a means of draining a section of the aqueduct tunnel for repairs or in anticipation of water overflow. The weirs were located near streams so the excess water could be diverted to them. The weirs also had openings at the top of the weir structure, hence providing a source of ventilation for the water and to help regulate the water flow through the tunnel.
Each waste weir had a sluice gate which diverted excess water out of the tunnel and into a nearby stream.
