2011-2012 Snow Gate Analysis

The winter of 2011–2012 in Sioux Falls was a mild winter on most accounts. This was to be our second true test for snow gates in two new areas of Sioux Falls. The lack of snow produced good savings in the snow removal budget, however, did not allow us to fully test the cost/benefit of snow gates. We have determined the data from this past winter to be statistically inconclusive and it would be difficult to incorporate the data into a model to determine the cost and efficiency of snow gates. The following is a list of factors that we used to reach this conclusion:

  1. First, the City of Sioux Falls averages 43 inches of snow during a typical winter season. The total snow accumulation from November, 2011 through March, 2012 was 15.9 inches. This is the second least amount of snow that has fallen in Sioux Falls since 1948.
  2. There were only two snow alerts issued during the winter, the first on January 20th when we received 4.6 inches of snow and the second time on February 23rd when we received 5.6 inches of snow. During both of these snow events the streets and parking strip area were absent of any accumulated snow.
  3. During each of the snow alerts we experienced a high number of calls in the snow gate areas for plowbacks due to drifting but did not receive calls for plowbacks in the non-gate area due to drifting. The wind and location of this test zone is the only conclusive reason for this result. We do not believe this is related to the use of a snow gate in this area. However, since it was in the snow gate area, the additional plow time for plow backs was captured.

The past two winters, the Street/Fleet Division has tested snow gates to determine the cost/benefit of incorporating snow gates citywide. We delineated two neighborhoods during the 2010–2011 snow season and delineated two different neighborhoods during the 2011–2012 snow season as test locations for snow gate usage. The collected data is a snapshot of costs/benefits in those 4 areas but is hard to extrapolate over a 73 square mile area of Sioux Falls especially given the very limited data collected during the 2011–2012 snow season. We have learned a large number of homeowners support the use of snow gates in the areas we have tested in the past two winter seasons. In order to get a more representative sampling of cost/benefit of snow gates for the entire city, it is our recommendation to test snow gates again in the upcoming winter season of 2012-2013. It is also our recommendation to increase the number of snow gates from three to six to provide a larger test of snow gates. Placing six snow gates in six different areas of the city will provide a better representation of our ability to mobilize and operate these units plus provide more reliable information to estimate the operating commitment needed if the decision is made to go citywide with snow gates.

We look forward to providing quality data to review that includes the benefits, the costs, and the potential safety concerns that could be derived by implementing snow gates. After the conclusion of the third test of snow gates in the 2012-2013 winter season, and provided we have a normal winter season, we are confident we will be prepared to make a recommendation on the implementation of snow gates city wide.