Date of Award
Campus Access Thesis
Master of Science (MS)
Environmental Sciences/Environmental, Earth & Ocean Sciences
Ellen M. Douglas
Eugene D. Gallagher
Low head dam removal is becoming increasingly common in the United States, with 72 dams being taken off rivers during the year 2014. While extensive research exists for the impacts of these removals concerning sediment transport and the health of instream organisms, characterizing changes in water quality has remained a challenge to quantify.
The removal of the Off Billington St dam from Town Brook in Plymouth, Massachusetts in 2013 marked another step in restoring a historic spawning pathway for common herring (Clupea harengus). During the dam removal operation, water temperature was monitored upstream and downstream of the impoundment. Analysis of the data revealed a shift in the diurnal heating cycle of fifty-three minutes (P=0.000029), utilizing the Mann-Whitney U Test. Comparison of seasonal curves before and after the dam removal reveal that variability is decreasing (std dev 2013: 3.12, std dev 2014: 1.52).
Efforts to study a subsequent dam removal immediately upstream were deterred by construction delays. Guidance is offered in the discussion concerning proper protocols when engaging in long-term in situ monitoring of river restoration projects.
Conlon, Matthew D., "Changes in Water Temperature Patterns Following the Removal of a Low-Head Dam in Plymouth, Massachusetts" (2015). Graduate Masters Theses. 308.