Thornton Academy Postscripts Alumni Magazine Fall 2013 | Page 4

ST EM

On the Saco River with Tim Harder ‘98

An Acoustic Doppler Current Profiler (ADCP), mounted on the side of UNE’s Research Vessel (R/V
Llyr), enables Tim Harder to use sound waves to measure the depth and velocity of the Saco River’s
current. The data that Harder gathers can be used to create a profile of the river channel which Harder
then compares with past research to see how the river has changed during the last 20 years.
Confident and on a mission. That’s how Tim Harder ‘98
looks standing on the deck of University of New England’s
(UNE) research vessel belonging to the Marine Science
Education and Research Center. This summer, Harder
took Postscripts on board to glimpse how he uses science
to address local environmental challenges. Harder’s
research focuses on the erosion and deposition of
sediment within the Saco River. Harder explains, “The
Saco River is the main source of sediment to the beaches
on Saco Bay, specifically Camp Ellis and Ferry Beach.”

with the town currently considering another U.S. Army
Corps of Engineers project to mitigate erosion at Camp
Ellis, which carries a price tag upwards of $22 million.”

If dramatic photos and TV footage of beach destruction
and flooding come to mind, then you have a sense for the
problem. Harder’s research maps out how silt, sand, and
gravel move down the river and “feed” the bay, or not.
Says Harder, “I feel that this research is particularly timely

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POSTSCRIPTS

“I take sediment samples
at various points within the
river, using a sediment
grabber and am currently
analyzing them to
determine their sorting
pattern and mean grain
size. This is a traditional,
and invaluable tool for
geologists to tell me what is
happening on the bottom,
and perhaps even the
source of the sediment.”