St. Charles County Transportation Plan 2030 - East-West Gateway ...

B-1.2. Comparison of MoDOT Roads to Region and State
To completely assess the safety of travel on MoDOT roads in St. Charles County, their crash rates
were compared to the values for the St. Louis region and state of Missouri. Table 21 shows these
values for Interstate routes, U.S. routes, numbered routes, and lettered routes.
Table 21
2004 3-Year Average Crash Rate Comparison
County - Region - State
Road Type St. Charles County St. Louis Region State of Missouri
Interstates 191.05 137.32 111.36
U.S. Routes 163.77 252.62 166.04
Numbered Routes 398.00 360.66 273.22
Lettered Routes 440.49 415.33 272.28
I-70 had a three-year average that was higher than the entire St. Louis region and the state average.
Many items related to travel on I-70 could explain why these numbers are so high. There are many
interchanges with high volumes of entering and exiting traffic which may be higher than in other
parts of the region and the state. Truck traffic is also higher than on other Interstates in the region.
On U.S. routes the three-year crash rate was lower than the region and the state. They include a
number of roads that carry substantial volumes of traffic yet have low numbers of crashes. This
probably will decline further once U.S. 40/61 is converted to I-64 and only U.S. Rt. 61 and U.S. Rt
67 travel through the County. Both these roads presently have low numbers and severity of crashes.
Numbered routes had a slightly higher crash rate than the region and state. These roads are heavily
traveled and serve a large amount of land use that creates considerable conflicts. Some of these road
segments, especially Rt. 94, in the rural part of the County, travel through very rough terrain. Many
date back 50 to 75 years and have poor alignment, bad sight distances, and no shoulders.
Lettered routes were also above the average for the region and the state, however, some of these
routes were not included on the list and would have less traffic and lower crash rates. Including
them would make the overall rate for the County lower than what is indicated.
B-1.3. St. Charles County and City Roads
The same methodology used for analyzing MoDOT roads was used to evaluate the safety on County
and city roads. Twenty-four road segments were selected after consulting with County officials.
They were the most highly traveled 1 (those carrying over 2,000 vehicles per day) and served the
most developed land use areas. The measures of number of crashes, crashes per mile, severity
ratings, and crash rates were derived from the crash data.
1
There are many other County roads but they do not carry high traffic volumes and have few crashes. Analysis of safety on
these roads was considered beyond the scope of this study.
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