Workers are completing the last stage of the restoration of Lower Wellingsley Brook, a small cold-water stream that drains directly into ­Plymouth Harbor, through a joint state and town project intended to improve not only the brook but also the surrounding environment.

The $90,000 project removed three small dams, cleaned up trash from the riverbed, destroyed invasive plants in the stream’s corridor while replanting it with native species, and placed pieces of wood such as tree stumps in the ­restored main stream channel and floodplain.