By Craig W. Anderson

Roundabouts are either a curse or a blessing to drivers who must negotiate the circle-drive that converts an intersection into an adventure for some but is a lifesaver to others.

According to the San Joaquin County Public Works department, a cash infusion will permit the county to spend funding on constructing roundabouts in rural areas of the county the most recent proposed locations near Linden.

What is a roundabout?
What, exactly, is a roundabout? According to Public Works it is  “…a type of circular intersection, but is quite unlike a neighborhood traffic circle or large rotary. Roundabouts have been proven safer and more efficient than other types of circular intersections.”

The basics of roundabouts are: traffic travels counterclockwise around a center island; vehicles entering the roundabout yield to traffic already circulating; and they have curvature that results in lower vehicle speeds throughout the roundabout.

According to the Insurance Institute for Highway Safety, at locations where roundabouts have replaced stop signs and/or traffic signals: crashes decreased 39 percent; injuries decreased 76 percent; fatalities and/or incapacitating injuries decreased 90 percent. And, overall, it’s claimed that more traffic can flow through a roundabout than through a conventional intersection with its stop-and-go traffic.

What about roundabouts in ag areas?
However, it’s not known if any studies have been done using the type of agricultural-oriented roundabouts that would be needed in a rural, ag-active region, or if studies were done during harvest time when vehicular traffic is much higher than non-harvest times of the year. Also, can caravans of large harvesters actually traverse a roundabout more quickly than a traditional stop sign/light controlled intersection?

The proposed locations for these unique circular roadways are: Duncan Road/Comstock Road; State Route 4/Jack Tone Road, State Route 26/Jack Tone Road; Dustin Road/Liberty Road and Byron Road/Grant Line Road. 

The county said in a statement that “…these roundabouts are basically proposed for safety reasons or to alleviate congestion at these intersections.”

The statement also notes, “San Joaquin County does realize that agriculture equipment has had difficulty with many roundabout designs.”

Roundabout testing
Therefore, the county held a roundabout testing day at the corner of Baker Road and Duncan Road on the large asphalt yard. Dodgie Vidad from the engineering division of Public Works informed the 30 assembled farmers, truckers and haulers and interested bystanders of the sprayed and orange-coned area that represented the roundabout on the yard. A number of vehicles were on hand to drive the circular, full-scale mockup to determine how and if it would work.

“At least the county tested it,” said SJFB Executive Director Bruce Blodgett. “They just didn’t go ahead and build them. It’s good that Public Works is getting feedback from those who will be affected if these roundabouts are built.”

The test day was to ascertain if the vehicles could get through the roundabout, if the design required modification and how the circle roadway would affect its location, i.e., if right of way, easements, property and other land issues might be raised if the circle cut into too much ag land.

The vehicles assembled for test runs through the roundabout included a field harvester, a wide load tractor-trailer hauling a Caterpillar D-10, a 470 Case tractor pulling a 40-foot long land leveling disc/roller/drag combination, a large hay bale hauling truck, and a high wall trash hauling combination. A sprayer unit and walnut trailers were also on site but didn’t test the circle. Vidad said the county has “taken a look at four-way stops, including those with flashing red lights and accidents at four-ways over time and there will be some right-of-way taken by the roundabouts. There will be curbs, too.”

He added that because of the curved nature of the roundabout, there are no straight-on approaches inside it “so any accidents won’t be head on but at an angle and because of the slow speeds, collisions will be much less dangerous. Roundabouts are proven to be safer.”

Kenny Watkins said, “Trucks with heavy loads will have to slow from 55 to 15 mph and could lose their load in the turn. I also have concerns about other drivers not stopping or trying to cut in on traffic and interfering with the ag equipment already in the circle.”

“Tires could blow out on the curbs,” said an audience member.

“Apparently these are designed using auto and truck standards but ag equipment of various large sizes aren’t taken into account,” Blodgett remarked.

Oversized vehicle tips
Trucks and oversized vehicles are noted in a “Tips and Guidelines for Drivers, Bicyclists, Pedestrians and Oversized Vehicles” section of the Public Works/Roundabouts website.

About trucks and oversized vehicles it says: “When entering the roundabout on a multi-lane approach, trucks may claim both lanes; avoid circulating side by side with other vehicles; a truck apron is provided in the central island for the tracking of trailer wheels.”

Blodgett said, “The county isn’t aware and had no idea of what type of businesses we have out here. In addition to the usual large ag vehicles and equipment, we also have steel haulers, truss carriers, big tractor transporters, cattle trucks and others.” The test vehicles drove through the delineated roundabout and the larger, longer of the group found it to be a very tight fit with many large highway cones being flattened. The indications were that perhaps a redesign was in order to simply make the roundabout larger to accommodate the big vehicles.

Mike Staples, owner of Hammer Truck, a large equipment hauler in Woodbridge who grew up in Linden, said, “Safety is the county’s and our first concern and toward that end, these roundabouts should facilitate us first, not cars or trucks. Also, the fact that equipment is large and will get larger has to be considered.”

Staples drove the D-10 hauler and only his driving experience saved many cones but entering the central area was, in the case of the long and wide trailers, unavoidable.

Staples and others pointed out that during harvest and other times when the roads tend to be crowded with farm implements and vehicles, different routes may be required to avoid the roundabouts and this means more time and expense.

However Public Works is confident roundabouts can be built to take care of large ag vehicles and equipment while being lined to handle autos and normal semi-trucks. According to the county, agriculture will be accommodated.

The assembled crowd agreed that there were many different opinions voiced regarding what could, and should, be done. “It’s positive that this mockup test took place,” Blodgett said. “But this roundabout seems better suited for urban traffic than agriculture.”