THESE ARE SEGMENTS OF THE WSDOT SR162 CORRIDOR STUDY AND OUR QUESTIONS ABOUT THEM
Concerning the traffic model the WSDOT is using:
QUESTIONS: If the DOT persons who designed the roundabout don’t know the data entered into the model they described at the Public Safety Meeting, how can it have been designed to accommodate the demand? Who entered the factors into the model? What factors have been entered into the model you have used to predict the effectiveness of the roundabout you are proposing for 128th Street? Since we have a couple of engineers in our group, we would like to know all the factors that have been entered into their computer model that is predicting how this roundabout will function.
Concerning new development in the greater Orting area:
QUESTION: Has the projected traffic from the new developments to the north and west of Orting and the expansion of Washington Rock Quarries and others been calculated and included in the DOT’s roundabout efficiency and traffic flow projections?
Concerning safe space in the roundabout traffic to enter and traverse it:
QUESTION: With the volume of traffic currently expected at the McMillin roundabout (2 seconds apart) and considering the current composition of our traffic (trucks, buses and cars), what is the safe “gap” space between vehicles that will allow Orting traffic to enter, cross through a lane and pass through the roundabout northbound? Please provide the data that verifies that Orting traffic will have a safe space to enter and cross lanes in order to travel north.
Regarding accidents in a roundabout with the traffic ours will have:
QUESTION: What documentation or data does the DOT have on the frequency or occurrence of minor accidents in roundabout operations such as the one they are proposing for McMillin: volume and nature of the traffic mix and direction of flow?
“Societal Costs” in projecting the cost of a signal vs. a roundabout:
QUESTIONS: How does Societal Costs that relate to accidents factor into the cost of building an intersection when the DOT pays nothing when an accident happens? Roundabouts cause more accidents, though minor, those costs have not been included in the cost of the roundabout. The DOT has charged $72,000 against the cost of a signal that have been documented to be minor and $0 against the cost of a roundabout in the Societal Costs category. Please explain that.
Regarding the cost of roundabout repairs:
QUESTIONS: Will the DOT please provide documentation of repairs to industrial roundabouts over the past 20 years? Will the DOT provide some actual signal maintenance costs for an intersection similar to the one proposed at 128th?
Regarding the “hazard” of intersection signal poles and accidents:
QUESTION: Over the past 10 years, how many signal poles have been involved in an accident on the SR162 corridor?At what rate are signal poles involved in accidents and what level of injuries have resulted?
Regarding the frequency of accidents:
QUESTION: Can the DOT provide evidence that there will be fewer than 3 accidents per year at this intersection in the future with a roundabout, knowing that roundabouts generate more minor accidents as research has shown?