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

By 2030 volumes are expected to reach 80,000 across the Missouri River. Peak hour volumes, as
a percent of daily traffic, will be higher than those on I-70 and I-64 and are estimated at 12 percent.
The high direction of travel will also be more at 65 percent. This will cause peak hour volumes in
the high direction of travel to be about 6,200. With five lanes in both directions across the river,
peak hour volumes for each lane will be about 1,250 vehicles. Even with converting to pcphpl, this
provides LOS C and no congestion. From the bridge to Rt. 94 volumes will drop slightly to 75,000
and it will lose a lane in each direction. Using 12 percent for peak hour volumes and 65 percent for
the high direction gives 5,900 or about 1,500 vehicles per lane. Converting to pcphpl gives 1,600.
From Table 10 and 60 mph speed limit, this equates to a low LOS D with some congestion.
From its north junction with Rt. 94 through Harvester Rd. to Mid Rivers Mall Dr. Rt. 364 will take
the place of Rt. 94. It will carry between 70,000 and 60,000 vehicles a day. Peak hour volumes will
be less of the daily totals in the old Rt. 94 corridor or about 10 percent. The directional split in
traffic will be more equal at about 55/45 percent. With four lanes in each direction this equates to
a high of about 1,000 vehicles per lane or LOS C with no congestion.
When Rt. 364 is completed from Mid Rivers Mall Dr. west to the I-64/Rt. N interchange, volumes
will increase due to growth in the corridor and its connection to I-64. Since this part of the
improvement is not included in Legacy 2030, forecasts with this addition have not been made. It
is expected that the increase will not cause the road to reach its capacity, therefore, it will function
without any serious congestion problems. However, its completion will greatly aid traffic
congestion on both I-64 and on I-70.
Rt. 370
Traffic across the Missouri River has grown steadily. Year 2004 volumes indicate 61,000 at the
river dropping to 58,000 near the Elm Ave. interchange. West of Truman Rd. it was 51,000. By
2030 it is expected that volumes will reach 85,000 at the Missouri River, 65,000 west of Elm Ave.
and 60,000 west of Truman Rd.
At the Missouri River during the peak hours in 2030 it will have 10 percent of the daily traffic and
a 60/40 directional split. For a six-lane road, the peak direction will have 5,100 vehicles or 1,700
vehicles per lane. Converting to pcphpl gives 1,800. Table 10 and a 60-mph speed limit indicates
LOS D with moderate congestion. From Rt. 94 through the Elm Ave. and west to I-70 it remains
a six-lane freeway and volumes drop resulting in a better LOS C with no congestion.
One item of note is the fact that some traffic from I-70 finds Rt. 370 a useful bypass eliminating the
need for travel on highly congestion I-70. This is especially true for vehicles traveling to and from
the north part of St. Louis County or through the region and wanting to avoid traveling through
downtown St. Louis. It also is greatly used if there is an incident on I-70 that causes any disturbance
in traffic flow. At these times volumes can be much higher and the congestion can be quite acute.
C-2.2. Expressways
As noted previously, traffic flow on an expressway differs considerably from that of a freeway since
it has at-grade intersections and many of them may be signalized depending on the road’s location.
The HCM recognizes this difference and the analysis of the following expressways follows that of
the HCM. Table 11 in Chapter III provides the LOS values for these expressways.
106