Using native plantings not only helps reduce maintenance costs but also erosion control. Mark Masteller, Iowa DOT chief landscape architect says that the native species have adapted over time to the wide temperature and moisture variations between seasons. “The deep root systems help choke out weeds, minimizing maintenance and also help stabilize the soil along the roadside to reduce erosion,” Masteller says. v

Software vs. Snow Drifts

SnowMan is a user-friendly, desktop software package that works on laptops in the field to help engineers design roadways less likely to be plagued by snow drifts and allow maintenance personnel to more precisely situate snow fences to reduce drifting on existing roadways.

The software is based on a combination of knowledge about the fluid mechanics principles that underlie how snow blows and drifts, and climatological data about seasonal snowfall and wind velocities.

“Wind carries particles of snow along just the way that a river will carry silt and mud,” said lead developed Dr. Stuart Chen, a professor of civil, structural and environmental engineering with the University at Buffalo, N.Y. “Snow fences introduce turbulence that causes the wind to deposit some of the snow particles it has been carrying onto the ground behind the snow fence, leaving the roadway clear.”

But deciding how to configure and place those snow fences is not an exact science, Chen said.

“Snow fences are typically erected according to general knowledge about an area where blowing and drifting occurs,” said Darrell Kaminski, regional design engineer for the Western New York region of the New York State Department of Transportation who helped develop the software. “Fences are typically a standard height and are placed a certain number of feet from a roadway.”

A more precise approach would require maintenance personnel to obtain climate data for an area to determine how much snow and wind that area experiences in a season and then to run a series of calculations to determine the best height and placement for a fence in that location. The big advantage of SnowMan, according to Chen, is that it provides all of these capabilities to the user automatically, whether the goal is to mitigate a specific blowing and drifting problem or to design a new roadway that minimizes blowing and drifting.

“SnowMan allows users to analyze different types and heights of virtual snow fences in a variety of distances from a given roadway so that it is possible to come up with the best solution for a specific site and climate,” said Chen.

“For the first time, it allows us to be precise about where to put snow fences,” said Chen.

“The NYSDOT believes that the SnowMan software will significantly advance the implementation of passive snow-control measures both within New York State and nationwide,” said Joseph F. Doherty, senior civil engineer, operations division, NYSDOT, Albany. “We expect improvements in highway safety, lower winter maintenance costs and reduced impacts on the environment as a result.”

Chen designed the program with former UB graduate student Michael Lamanna, Kaminski and Ronald Tabler of Tabler and Associates, Niwot, Colorado, one of the country’s leading experts in the mitigation of blowing snow. The University is part of the State University of New York. v

For more information on handling drifting snow check out http://www.tablerassociates.comdownloads section.