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Sewer flow monitoring brings big benefits to communities
By Tawny Quast
C
rawling into a wastewater sewer manhole likely doesn’t make most
people’s bucket lists. But Ayres Associates’ municipal engineering
staff members in Fort Collins, Colorado, actually enjoy their time
spent in these large pipes to help their municipal clients.
Sewer flow monitoring involves placing a sensor into the wastewater flow.
The sensor measures the depth and velocity and uses those parameters to
calculate the flow rate. Ayres Associates engineers place the sensors in the
sewer pipes and hang a data collector near the top of the manhole.
The flow data then can used to calibrate a municipality’s wastewater
model, which is used to determine whether its pipes are undersized in
a particular location, what pipes need replacing, or what impact a new
development will have on the sewer system downstream, among other
things.
The northern Colorado City of Loveland has been working with Ayres
Associates on developing a sewer model that accurately simulates its
wastewater collection system. A computer model can simulate wastewater
flow but can be inaccurate without comparing the model to actual field
conditions, said Chris Matkins, water utilities manager for the City.
Loveland needed to understand the capacity in its sewer lines to plan for
infrastructure improvements and upgrades, Matkins said. “Basically we
build the model, and then we use flow monitoring to verify the results,”
he said. “The decisions you are making are very large, expensive decisions.
You’re talking about costly infrastructure upgrades, and you need to make
sure you’re basing your decisions on good results.”
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