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(swish sound)

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- [Voiceover] As traffic
volumes increase everywhere

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in Texas as the state's
population increases,

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TxDOT wants to determine

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if innovative intersection
alternatives are safer

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than typical intersections.

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To develop design guidance for TxDOT,

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researchers with the Texas
A&M Transportation Institute

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have conducted an analysis

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to determine the operational
and safety benefits

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of various intersection
designs, including roundabouts.

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- A roundabout as a circular intersection,

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and they've been used
nationwide and even worldwide,

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but largely in urban
and suburban locations

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where speeds are already somewhat lower.

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There is less known about how they operate

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in rural locations with
high speed approaches.

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- I think it was important
for this research specifically

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to kind of quantify some of the really,

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kind of the unknowns

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that we've had when it comes
to innovative intersections.

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So, innovative intersections
is a term that's been around

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for a while and it covers a wide range

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of nonstandard intersection designs,

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where the goal has been to
reduce the conflict points

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and to reduce the severity
of crashes that occur

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at a typical four leg
crossing intersection.

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- There's another kind of broad category

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of intersections called
innovative intersections

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or maybe alternative intersections.

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We looked at different forms
of those intersections.

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One thing that they have in common is

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that their design
characteristics are tending

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to accommodate left turn traffic

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in different ways than a
traditional intersection does.

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And so again, those are being used

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in a number of different
locations around the country,

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but they're not as
commonly found in Texas.

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And so TxDOT was interested

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in ways that those might be used here

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and how would we go about doing that?

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- The researchers went to two sites

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for roundabout data collection
and then another two

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or three sites, I believe, for
the U-Turn data collection.

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And then they looked at crash
history of existing locations.

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So, they pulled other state DOTs.

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They found locations across the, you know,

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the country that had been in place for

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at least five or six years or more.

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And so you're able to look

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at the before and after crash data.

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- We actually collected data

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at these types of intersections,

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both within Texas as
well as outside of Texas.

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With the field data that we collected,

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we used that to develop
micro simulation scenarios.

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And then we tested a lot
of additional scenarios

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that don't exist in reality,

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but a way to determine
how to change different

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design characteristics
to see what works best.

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Through our work, we have identified

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that roundabouts in
rural and rural locations

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with high speed approaches
can work in Texas.

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The data indicate that
they will perform properly

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if they're designed to
meet those conditions.

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On the innovative intersection side,

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they will work in Texas.

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We're able to provide some
guidelines for them to be used.

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- This project makes Texas roads safer.

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We have to apply the principles
that we've kind of outlined

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in the guidelines that the
research has put together,

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but ultimately, this project
makes Texas roads safer.

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- For more information

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and to find the publications
for this project,

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please visit the TxDOT research library

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at the link shown below.