This is a contemplation directed at any civil and/or environmental engineers that
might be on DK, and to all students of environmental science and environmental
The contemplation concerns the Detroit River International Bridge (DRIB) which is
planned for this location coming onshore in Michigan:
My contemplation is also directed to the designers and planners of DRIB,
the people of Canada who are paying the bill, US Departments of Transportation, State and Homeland Security, DTE Energy, and U.S. Steel, and Detroit-Windsor-area trade unionists who will build this bridge.
My fundamental contemplation is this:
What is the practical, technical and economic feasibility and
the potential operational effectiveness of using industrial
non-contact cooling water available in prodigous amounts
near the new bridge from DTE Energy, U.S. Steel and others for
beneficial re-use to create a structurally intrinsic cold weather
de-icing system for the bridge deck, the approaches and the
U.S.-side bridge toll/DHS plaza?
It may be too late in the design process to even consider anything
like this. However, such a project is the type of beneficial re-use
of waste BTUs that should be considered if we're going to address
a more holistic approach to energy, greenhouse gas control and
A structurally installed de-icing system could be used to make the
bridge safer and to maximize efforts at keeping road salt de-icers
off of the bridge for deterioration process control reasons.
To even speculatively explore the question is a fairly daunting and complex task, but
here are some thought processes and information that would be required to consider
You would have to gather complete database of information about non-contact heated water generation near the bridge, including typical cold-weather stats on wastewater
produced as to nominal maximum and minimum temperatures expected.
A literature search would need to be conducted about any uses found of heated
water for de-icing purposes in civil engineering practice and what problems were encountered. In order to ensure system sustainability the problem of water chemistry would be critical to ensure that corrosion did not cause leaks and other deterioration. You would have to create a physical heat transfer model for the bridge deck and approaches and a different one for the toll plaza to address the needed design element of how you would engineer the in-road-bed piping system.
The selection of the type of pipe used and how to address differential expansion and
contraction rates that would not cause structural failures would be a tough problem for
road bed design. It might be advantageous to create a modular type of system
for bridge and approach road decking that would be manufactured offsite and installed
on the bridge. The modular system of deck construction could use pre-stressed
concrete along with the pipes embedded in the deck. In such a modular system, you
would have to design a standard and easy method for pipe joints at the edge of the
As part of a system for heated water de-icing, you may also be
able to operate partial or complete tire washing to keep salt off of
If anyone on the list ever heard of any of this being ever attempted elsewhere as
part of road or bridge design, please let me know.