Mr. Thalheimer has overseen and performed several underwater acoustical studies involving measurement of hydro-acoustic sound levels with hydrophones. Great care must be practiced when measuring underwater noise due to the harsh environment, complexity of instrumentation, and multiple possibilities for errors. Mr. Thalheimer's work has served to ensure the protection of endangered marine species such as harbor seals, sea turtles and Atlantic sturgeon when exposed to severe underwater pile driving noise.
Example projects in which Mr. Thalheimer measured and evaluated hydro-acoustic sound conditions include the following:
- Walk
Rail Bridge Replacement Project, Connecticut Department of Transportation,
Norwalk, CT – The Walk
Bridge, which crosses the Norwalk River as part of Amtrak’s Northeast Corridor,
is being replaced with a new bridge. In
response to community concerns about potentially adverse effects associated
with construction of the new bridge, a comprehensive Construction Noise and
Vibration Control Program was proposed for CTDOT’s consideration to
implement. Of particular concern were
potential adverse impacts to endangered sea creatures (harbor seals and sea
turtles) at the nearby Maritime Aquarium. Existing conditions were measured, and future potential conditions were
predicted for air-borne noise and ground-borne vibration affecting aquarium
staff and visitors, and for hydro-acoustic noise levels inside several of the
aquarium’s water tanks. Later, noise, vibration and hydro-acoustic levels
affecting the Aquarium and its endangered species were monitored during a
month-long pile driving test program (TPP) involving nine test pile sites and
four different pile drivers.
- Great
Egg Harbor Bridge Project, New Jersey Department of Transportation,
Ocean County, NJ - Oversaw
implementation of the project’s underwater noise monitoring program in order to
protect Atlantic sturgeon and sea turtles from pile driving noise that might
adversely affect their reproductive patterns or potentially fatally harm them. Received
raw data as wave files from field staff, reduced, analyzed and evaluated the
results.
- Manahawkin Bay Bridge Project, New Jersey Department of Transportation, Ocean County, NJ - Developed the Underwater Construction Noise Specification for the project in order to protect Atlantic sturgeon and sea turtles from pile driving noise that might adversely affect their reproductive patterns or potentially fatally harm them. Codified the acoustical performance requirements for an underwater bubble curtain and for pile cap cushions. Performed underwater noise measurements using a hydrophone to ensure contractor compliance with specification limits.
