Caltrans next step in a bid to stop 120 Bypass eastbound drivers from making last second lane changes to head toward Modesto could involve placing K-rail leading up to the transition split to north and south bound Highway 99.
Councilman Gary Singh, who is Manteca’s representative to a working group involving Caltrans and the CHP to try to address safety issues on the Bypass, made that comment during Tuesday’s City Council meeting.
The council was preparing to accept various right-of-way involving the new alignment of Woodward Avenue and a future connection street from Atherton Drive to Austin Road that is part of the $154 million solution for 99-120 issues when the issue came up of the bollards that are now in place not being very effective.
The bollards were employed after efforts to post signs — and markings on the pavement — two to three miles ahead of the split to catch the attention of drivers had limited success at reducing last second lane changes.
Many of the bollards have been knocked down by drivers that still went ahead and made last second lane changes cutting off traffic in the right lane.
Such movements by drivers crates a slinky effect or stop-and-go traffic in the right-hand lane that heads into the transition ramp to southbound Highway 99.
It is the sudden stops that such lane changes trigger that has given the Bypass an accident rate seven times higher than the national average for a freeway segment.
It also is the leading cause of massive slowdowns and backups that can back up traffic for three to five miles even without an accident during peak commuter hours.
And while Singh stressed no decision has been made about adding K-rail it has been listed as the next possible step. He also noted the various agencies still want to try to do what they can to reduce the potential for carnage while the first phase of the $154 million adds a second transition lane to southbound Highway 99 in a bid to address the problem.
The first phase may not be done until 2023 or 2024. Work is supposed to start by the end of this year or early 2023.
That leaves more than two years with the current conditions that are likely to be made worse due to construction.
K-rail is a modular concrete or plastic traffic barrier used to separate lanes of traffic. They are commonly used to reroute vehicular traffic during roadworks and delineate the construction zone.
Examples of concrete K-rail can be found on the Main Street and Airport Way overpasses on the 120 Bypass.
The angled bottoms and parabolic shape of the K-rail minimizes the damage of a car-crash impact. When struck, the barrier forces the wheel slightly off the ground and deflects and absorbs much of the damage that may otherwise threaten drivers and passengers.
While the accident rate is seven times the national average, Caltrans in a study prepared to justify the project noted your odds of getting in a collision on the 120 Bypass as you near Highway 99 if you are trying to head south toward Ripon and Modesto is six times higher than the statewide average.
The state notes that motorists — impatient about the delay — will use the fast lane or inside lane to travel as far as they can to the split and then cut back into the much slower moving traffic in the right lane. That leads to rear-end collisions and an accident rate six times higher than the average for a California freeway.
To contact Dennis Wyatt, email dwyatt@mantecabulletin.com
