I think this goes here

[mattotoole]

@PotomacCyclist 95413 wrote:

The plans for Water Street at the Southwest Waterfront (The Wharf) include a shared space design, where pedestrians, bikes and cars will mix in a common zone. It’ll be a few years before that’s completed, so we don’t know how well it will work just yet. Maybe these designs work better when there are also bike trails/lanes nearby (but not in the middle of the mixing zone/shared space)?

It can all be in the mix like Granville Island in Vancouver BC, which has a cement plant with trucks coming and going, along with tourbuses and everybody else walking, biking and driving around. And it’s one of the world’s great waterfronts.

I spent a week or 2 there every summer for 9 years, with a bunch of architects/planners and engineers — a real treat for all of us.

[baiskeli]

To its credit, VDOT has installed or is installing several roundabouts at both rural and urban crossings lately.

This is VDOT’s page about roundabouts, which is very positive about them:

http://www.virginiadot.org/info/faq-roundabouts.asp

So there’s hope.

P.S. I love BobCo’s idea for Clarendon! Maybe it has a chance.

[dasgeh]

@bobco85 95411 wrote:

Curiosity killed the cat and I wanted to have a little fun, so I made a mock-up of what the Poyntonification of Clarendon Circle would look like based on a diagram of the Poynton traffic set-up:
After Poyntonification:

This is awesome. Thanks! Just curious: how did you do it?

[mstone]

@baiskeli 95426 wrote:

To its credit, VDOT has installed or is installing several roundabouts at both rural and urban crossings lately.

This is VDOT’s page about roundabouts, which is very positive about them:

http://www.virginiadot.org/info/faq-roundabouts.asp

So there’s hope.

P.S. I love BobCo’s idea for Clarendon! Maybe it has a chance.

Big problem is that two-lane roundabouts are much worse than single-lane roundabouts, and more lanes than that is a circus. Combine that with VDOT’s “never met a road that couldn’t use more lanes” philosophy and the possibilities are much more limited than they should be.

[bobco85]

@dasgeh 95427 wrote:

This is awesome. Thanks! Just curious: how did you do it?

I’m glad everyone likes it! I really just did it out of curiosity but had a little bit of fun with figuring it out while challenging myself with a short timeframe (only a half hour allowed for this).

To make the image, I used a diagram of the Poynton double roundabout that I got online at http://reconnectrochester.org/blog/2013/05/shared-space-reunites-village-divided/ and a screen shot from Google Maps of the intersection. I then cropped and applied a filter to simplify the double roundabout image. The tricky part was trying to position (rotation and size) the double roundabout so that no buildings would get cut off (part of the parking lot on the SE side actually loses 4 parking spaces), but I found a way to fit it in. After that, it was just drawing the shapes for the sidewalks/roads and extending the patterns used for each surface to mimic the original diagram.

BTW, here is the actual redesign that will be occurring at Clarendon Circle (construction estimated to start in spring 2015): http://projects.arlingtonva.us/projects/clarendon-circle/

[mattotoole]

@mstone 95431 wrote:

Big problem is that two-lane roundabouts are much worse than single-lane roundabouts, and more lanes than that is a circus. Combine that with VDOT’s “never met a road that couldn’t use more lanes” philosophy and the possibilities are much more limited than they should be.

The two lane ones where you can exit the roundabout from the left lane are an abomination. I don’t recall ever seeing these in the UK. Sadly they’re popping up like weeds all over the US, like around Bellingham WA. VDOT has been doing these too.

Can we embed Google maps here?

[Brendan von Buckingham]

The secret to Poyntonifying (ha!, take that spell check) Clarendon is to merge all two-lane directions to one lane prior to entering the Poynton then not having any traffic lights. The merge slows down traffic, the poynton and its islands slow down traffic more, no lights means no one ever has to stop.

An intersection where everyone goes 5 mph means no one has to stop and throughput is higher than current practice of queuing, waiting, stopping, zooming.

[KLizotte]

@mstone 95431 wrote:

Big problem is that two-lane roundabouts are much worse than single-lane roundabouts, and more lanes than that is a circus. Combine that with VDOT’s “never met a road that couldn’t use more lanes” philosophy and the possibilities are much more limited than they should be.

That’s because they are *not* designed properly in this country. Go to Iceland to experience roundabouts that have two lanes but do not allow dangerous lane crossovers and keep traffic moving (there may be some other countries but this was the first place I drove on a roundabout that funneled traffic correctly. It truly was an aha moment even though we had a lot of them in New England when I was growing up.) When I lived in the UK, there were roundabouts everywhere and most worked quite well, partly because of good design and partly because drivers there were so used to them.

[mstone]

@KLizotte 95460 wrote:

That’s because they are *not* designed properly in this country. Go to Iceland to experience roundabouts that have two lanes but do not allow dangerous lane crossovers and keep traffic moving (there may be some other countries but this was the first place I drove on a roundabout that funneled traffic correctly. It truly was an aha moment even though we had a lot of them in New England when I was growing up.) When I lived in the UK, there were roundabouts everywhere and most worked quite well, partly because of good design and partly because drivers there were so used to them.

They may work better because people are more used to them, but I fail to comprehend how you can design a two lane roundabout with no lane crossings. The rule of the road in Iceland is that the inner lane has the right of way, but that doesn’t change the reality that once drivers need to be looking in two directions at the same time, you’ve lost most of the benefit of the roundabout. Current best practice AFAICT (as in Poynton) is to simply use a one lane roundabout. If the drivers are too aggressive to merge to one lane, they’re probably going to be too aggressive to use the roundabout in any case.

[Brendan von Buckingham]

Don’t put any lane markings in the round about at all. Let drivers slow down even more and sort it out themselves.

[americancyclo]

@PotomacCyclist 95413 wrote:

Seven Corners could use a similar makeover.

Three circles?

[dbb]

@americancyclo 95471 wrote:

Three circles?

If we can get the count up to five, it might help the region’s bid for the Olympic games in 2024

[mstone]

@dbb 95473 wrote:

If we can get the count up to five, it might help the region’s bid for the Olympic games in 2024

So, one convincing reason not to do it.

[PotomacCyclist]

@Brendan von Buckingham 95457 wrote:

The secret to Poyntonifying (ha!, take that spell check) Clarendon is to merge all two-lane directions to one lane prior to entering the Poynton then not having any traffic lights. The merge slows down traffic, the poynton and its islands slow down traffic more, no lights means no one ever has to stop.

An intersection where everyone goes 5 mph means no one has to stop and throughput is higher than current practice of queuing, waiting, stopping, zooming.

Poynton may need to be added to the Forum Dictionary, as a noun and a verb. A Poynton can describe the double roundabout or more generally, a road intersection design based on shared space principles. To Poynton might reflect the act of redesigning an intersection according to those principles. Do these definitions need to be clarified or refined further?

[Author]

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