Focus Investigates: Speed Limits in Marshfield

The Ins & Outs of Speed Limits in Marshfield

It’s the omnipresent gripe of drivers everywhere: speed limits. With the mission to discover why exactly speed limits are what they are here in Marshfield, FOCUS did some investigating. Here’s what we found:


In the City Limits, the City of Marshfield is responsible for setting speed limits. Speed limits are first approved by the Board of Public Works, and then Common Council. The City Engineer proposes changes to the Board of Public Works after extensive study and discussion with others, including the Police Department.

“There is a lot of research out there, including the AASHTO federal book for designing highways,” said City Engineer Tom Turchi. “From that, I can make recommendations on why a street should be set where it is.”

25 MPH is the standard speed for residential areas in the State of Wisconsin (while, for example, Minnesota is 30 MPH).

This means that unless posted otherwise, the speed limit is 25 MPH within City limits.

The goal when setting a speed limit is always safety, both of drivers and pedestrians. Setting a speed limit involves engineering, physics, and math.

“When you’re trying to set a speed for roadway you figure out what the 85th percentile is and try to set to the nearest 5 MPH,” said Turchi. “What this means is that 75/100 of the people using the road are within 5 miles over or 5 miles lower than that speed. We use things like tube counters to determine what the 85th percentile is.”

When setting a speed limit, traffic volumes, counts, and patterns, streetlight presence, population of houses in the area, and pedestrian traffic are all taken into consideration.

“We have 10 traffic counters- two that can actually classify vehicles and collect speeds,” said Turchi. “When you take a look at traffic counts, you can determine what kind of road facilities are needed, whether you need more lanes, designated turn lanes, etc. We are able to look at traffic crashes and how that plays into the big picture.”

Turchi added that having uniform speeds has been shown to reduces crashes, making roadways safer. Also helping to reduce crashes is clever engineering.

“What can you do to an intersection to stop traffic crashes? North Central is a great example,” said Turchi. “Before the reconstruction in 2000, the rate of crashes between Harrison and McMillan was in excess of statewide average. In 2000, the medians were put in. In just the first year alone, we saw a 56% reduction in traffic crashes. That helps tremendously. It was a huge change in conditions out there.”

Crashes have trended downwards for years, but have recently begun to increase. Turchi credits the spike to distracted driving, a result of the increased prevalence of cell phones.

Overall, however, through the use of various engineering software and traffic studies, City engineers have been able to plan reconstruction projects with traffic safety in mind.

““When you take a look at the big picture, the engineering division has reduced traffic crashes in our community by 50% between 1996 and 2012. Good engineering and design is the best way to do it,” said Turchi. “Little by little, we are working on that. Each project that we do, we look at what we can do to reduce crashes.”


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On Central Avenue in the City of Marshfield, there are four lanes, several driveways, and many turning movements. With more than 10,000 cars traveling every day on North Central Avenue alone, the City opted to keep the 25 MPH speed limit throughout the City.

“We want to keep traffic running a little slower to reduce those issues,” said Turchi.

“Crashes happen at intersections and the more cross streets you have, if you add speed as a factor into that, you’re just increasing the chances for additional crashes,” said Police Chief Rick Gramza.

In 2006, the speed limit around the Marshfield Clinic campus was reduced from 25 MPH to 20 MPH, however reducing speed doesn’t always lead to the same level of slower driving.

“The perception is if a speed limit is reduced, people will drive slower,” said Turchi. “That’s not the case. “It’s not always good to lower the speed limit, as you might not always get the results you’re looking for.”

For example, when the speed limit on St. Joseph’s Ave was 25 MPH, the average driver went 32.85 MPH. In 2007, after the speed limit was changed to 20 MPH, the average speed went 30 MPH.

“So, if you take a look at the speed limits at 20, we basically saw people are still driving 10 MPH over the speed limit,” said Turchi. “Overall, it only reduced the actual traffic speed by 2.85 MPH. Dropping it 5 doesn’t make it function the way you want it to. It might actually make the situation more hazardous, because people think others are driving slower than they actually are.”


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As with any law, it is only as effective as its enforcement.

“The only way to get that speed lower is enforcement,” said Turchi. “However, the PD can’t be everywhere at all times. Especially during the school year, they concentrate around the schools. It’s up to each driver to obey the limit. Ideally, if you don’t speed in someone else’s neighborhood, then they won’t speed in yours.”

Residents often inquire about having a stop sign put near their house, but contrary to popular belief, studies show that this doesn’t actually result in safer roads.

“Stop signs are not designed to be used as speed control,” said Turchi. “The Institution of Transportation Engineers has actually done studies. What happens is people start making up the difference if they have to stop more. Furthermore, when a stop sign is put where it is not needed, people blow through it. A lot of intersections operate just fine being uncontrolled.”

According to Gramza, driving slow is just as dangerous.

“I think there are challenges and we live in a community where there is an older population of drivers and with the Clinic you have an excess,” said Grama. “If the speed limit is 35 there’s the expectation that the person in front of you is going 35.”

Turchi said that the most important thing drivers can do is pay attention.

“The bottom line is pay attention, be aware of your surroundings,” he said. “When you take a look at inattentive driving or failure to yield, in almost every instance somebody was driving too fast, in bad conditions, didn’t have control of their video, or weren’t paying attention. The latter is a very common problem.”

Gramza agrees that adjusting speed limits is not the answer, rather drivers and pedestrians need to be vigilant when on the road.

On a related topic, despite popular belief, there is no “end of month quota” officers need to meet.

“The goal is to have our officers active. It’s not uncommon for us to have officers pick up their stops, but they don’t have a number to hit every month,” said Gramza. “There is no contest or anything like that.”

“Safety is the biggest thing,” said Gramza. “Our job and goal is the educate the community, and we can educate through enforcement.”

“People tell us of areas to enforce and our goal is to often just be a presence so that people will police themselves,” he added. “The only thing keeping someone from speeding is themselves. Speed is almost always a factor in a crash, because it lessens your reaction time.”

News Desk
Author: News Desk