I can't believe there's a 'Shire' in Bend, OR. I'm doing a roadtrip through Oregon next month...I just may have to stop by and see this for myself. With their foreclosure problems, perhaps I can purchase Bag End for a song.

by Chris Loos on Aug 14, 2008 11:24 am • link • report

re: the bike rider who had their bike cut from the bike rack at Union Station. I think Union Station still belongs to the feds ... (I don't think the "District" played a part over what happened to her bike.)

by Lance on Aug 14, 2008 12:08 pm • link • report

David, how is this relevant to the District when DDOT routinely reduces the ITE formulas by 50% and developers, in their traffic studies, have reduced the ITE estimates by as much as 65%?

Also, this seems to have no relevance whatsoever to the need for parking for residential buildings, where our current minimums are far below vehicle ownership rates.

by JR on Aug 14, 2008 12:09 pm • link • report

Ditto to Lance's comment: I wish the crummy management at Union Station didn't get placed at the DC gov's feet. DC gov might have bike issues (plenty) but this wasn't on their watch. What is with the managers there anyhow??

by Sophiagrrl on Aug 14, 2008 12:11 pm • link • report

JR,

The ITE numbers are built on an entirely suburban model. Even a completely suburban development within DC would be unlikely to cause the kind of impact predicted by ITE. Not reducing those numbers would be intellectually dishonest.

The issue, of course, is asking why a set of standards for a completely different system (auto-dependent suburbia) are the default for an urban area like DC?

Make the right thing easy. TOD shouldn't have to jump through hoops to prove its worth.

by Alex B. on Aug 14, 2008 12:20 pm • link • report

Alex, David presented a study claiming that the impact predicted by ITE is too high for areas near Metro. However, DDOT has already taken that into account, and some developers have actually taken excessive reductions in the ITE numbers—far beyond that shown in this study. Montgomery County had developed trip generation rates for use at Metro stations based on actual experience. DDOT uses trip generation rates that are actually significantly less that the ones Montgomery County uses for comparable areas, understating the impact.

My point was simply that David’s post seemed to imply that DDOT was using excessive trip generation rates in evaluating traffic impact based on statements about what other cities might be doing, when, if anything, DDOT is taking excessive reductions in the traffic generation rates.

by JR on Aug 14, 2008 12:37 pm • link • report

JR,

I think you need to read David's post again. He never mentions DDOT with regard to ITE, but rather 'many cities.' And many cities do, in fact, take the ITE numbers as gospel despite their poor applicability to urban situations (even without great transit service!)

I'm familiar with ITE rates. I work with them a lot. DDOT should be reducing their trip generation numbers. Furthermore, there are two different things going on here: One is a matter of analysis, and the other is a matter of policy. A set of numbers may say that X parking spaces are needed, but we might set a policy to require Y parking spaces, as Y (regardless if it is higher or lower than X)is in place for some larger goal.

by Alex B. on Aug 14, 2008 1:28 pm • link • report

JR: I wasn't saying anything specific about DDOT. This blog isn't just about the District, and we have big TOD projects in MoCo, PG, Arlington, Alexandria, Fairfax, Loudoun and more. (The Shire isn't relevant to the District either, or even Greater Washington).

by David Alpert on Aug 14, 2008 1:56 pm • link • report

Alex, In my post, I was simply pointing out, as you have, that David's observation about what might be done in many cities bears no relevance to how traffic studies are done in the District. You seem to be trying to make the same point. The casual reader of David’s post might not have realized that DDOT doesn’t use the ITE rates, but generally takes a 50% reduction. David did not say whether DC was among the “many cities,” nor did he provide any information about what cities might be. In recommending the elimination of most minimum parking requirements in DC, David and others have frequently mentioned that “many cities” base minimum parking requirements on ITE standards, never mentioning that DC’s minimum parking requirements are generally lower than those in other cities and significantly lower than the ITE standards.

The link provided in David’s post only compared traffic generation in several TOD areas with ITE rates, and did not state that any cities used ITE rates in their traffic studies. The study looked at a number of TOD projects in four cities, including Arlington, Virginia, where the residents of the TOD projects owned 1.1 to 1.3 vehicles per household, compared with the county average of 1.4 vehicles per household. This is far higher than DC's minimum parking requirements of 0.25 to 0.5 for apartment buildings.

The study also included a projection of the household types that would live in the TOD areas: singles, couples and other households with no children were projected to be 79.2% of the TOD households, and married couples with children or other households with children would be the other 20.8% of the households in the TOD areas.

by JR on Aug 14, 2008 2:11 pm • link • report

It is not correct that Montgomery County trip generation rates correspond to actual experience at TOD. The Bethesda Naval Hospital EIS projected traffic from the existing buildings using the MoCo procedures, and actually measured traffic through their gates. The projected traffic was approximately double the actual traffic. See here for citation:

http://www.actfortransit.org/docs/BRAC.html

Also, here's some background on Sam Schwartz's client:

http://www.innerpurpleline.org/townofChevyChase.htm

by Ben on Aug 14, 2008 2:38 pm • link • report

Ben, Have you checked Montgomery County’s LATR? You seem to be looking at an environmental impact statement, not a traffic study. Appendix C of the 2008 Montgomery County LATR gives the trip generation rates for certain CBD’s, but does not include the area around the NIH Metro stop. Appendix B provides for reductions in trip generation rates based on distance from a Metro station, with a 50% reduction for the morning rush hour if a site is within 1,000 feet, straight line distance, of a Metro station.

by JR on Aug 14, 2008 3:20 pm • link • report

JR - The rates far exceed the actual rates. And the reductions are much, much less than 50%. The 50% reduction for office uses is only in the morning rush hour, which is irrelevant because the peak traffic conditions are usually in the evening rush. In the evening rush, I only see an 8% reduction for an office building 800 feet from a Metro entrance. That is ridiculous.

Similarly, looking at the residential numbers. In downtown Bethesda, Silver Spring, and Friendship Heights, it says a 100-unit high rise generates 30 trips in the peak hour. For a 100-unit high rise in the middle of nowhere, the number in Appendix B is 40 trips in the morning peak hour and 45 in the evening peak hour. The true traffic generation rate in these downtowns is much, much less than 30 trips in one hour per 100 units.

I have also heard that the LATR trip generation rates for retail are out of whack by a greater factor than for residential - I can't speak to that myself, but the empty garage in Columbia Heights surely suggests that traffic engineers are doing something very wrong in that area.

by Ben on Aug 14, 2008 4:07 pm • link • report

"Reconnecting America finds that transit-oriented development generates 50% fewer vehicle trips compared to conventional development."

No they didn't. They found that TOD generates 50% fewer vehicle trips compared to conventional developments in the FOUR PLACES that they studied. Which happen to be dense, transit friendly places like Portland and DC. Look at TOD in Dallas or Atlanta, and you'll find the numbers are far, far lower. TOD is a great thing, but the report is poorly written and not rigorous at all. (it does a great job of proving that TOD works in - surprise! - denser places with good transit access, high congestion, and restrictive parking policies.

I am of total agreement, though, that the ITE numbers are skewed way towards suburban style planning.

by Jarrett on Aug 14, 2008 11:07 pm • link • report

“The true traffic generation rate in these downtowns is much, much less than 30 trips in one hour per 100 units.”

Ben, is this statement based on actual traffic counts? You compare 30 trips with the 40 morning peak hour trips and 45 evening peak hour trips that Montgomery County uses for other parts of Montgomery County, but didn’t mention that the ITE trip generation numbers for that building would be 56 morning peak hour trips and 55 evening peak hour trips.

Is your calculation of the “true traffic generation rate” based on actual counts, or did you assume that it should be about 50% of the ITE rates, or is it based on how many workers you estimated would be driving to and from these buildings at the peak hours. If you estimated it, did you also take into account the fact that Montgomery County assumed that 25% of the morning peak traffic for the 100 unit building were vehicles arriving at the building and half the evening peak traffic were vehicles leaving the building? Approximately half the morning rush hour trips from the building began between 8 am and 9 am. Many of the households in the these areas have more than one worker and approximately 40% of the workers drive to work alone while 45% take public transportation. Our traffic analysis should to be based on what people actually do, and not on what you might like them to do.

by JR on Aug 15, 2008 7:58 am • link • report

JR - The new Cervero study shows, that in the areas they studied in Virginia that are really mixed use areas, reductions in the ballpark of 60 to 70%. The one building they studied in Maryland is the Avalon at Grosvenor, where there is essentially nothing to walk to except the Metro, and they got much less reduction. Also, I have counted traffic leaving the building I live in.

Also, remember that many of the people in these buildings are retired. In Friendship Heights, I'm sure the percentage of units with zero workers far exceeds the percentage with two.

Also, remember that Montgomery County only lets you use the numbers we're talking about here at three Metro stations. At the others, even Wheaton and White Flint where there is or will soon be moderately walkable mixed use development, you use higher numbers. The ITE minus 15% in the Bethesda Naval EIS was used because they were specifically instructed by the County Planning Board staff to use those numbers and ignore the empirical data that they gathered.

Jarrett - I agree with your basic point, but notice that some of the areas studied were suburban commuter train stations that had only rush hour service. I find it somewhat surprising that they had as much reduction as they did.

by Ben on Aug 15, 2008 8:51 am • link • report

Is it ever moral to steal a bike? There is an unlocked bicycle at *metro station withheld* that has been there for a week. It is slowly "losing" its parts. It has a broken rear rim, missing seat, missing handlebar grip, and looks like it's in need of a tune-up. Other than that, the frame looks clean and in good shape. I am worried that WMATA is going to remove the bike and send it to the landfill, rather than donate it to an organization that fixes bikes. I would like to post a note on the bike stating my intentions, wait a week, then take it and fix it for donation, or just donate it to Phoenix Bikes in Arlington.

Any thoughts?

by Michael P on Aug 15, 2008 11:16 am • link • report

I would say it is not your bike and therefore not your decision. I get it that it's a shame and all that, and all the other nasty things that's happening to it. Still...

by Jazzy on Aug 15, 2008 1:00 pm • link • report

The new Cervero paper, highlighted in David’s post, includes a discussion of TOD parking in residential projects. The lowest parking ratio discussed is 1.1 spaces per unit as used in Arlington. The 1.1 spaces per unit is then compared with higher parking ratios used in some Prince George's, Maryland TOD projects.

This parking TOD ratio is higher than any current minimum parking requirement for residential projects in DC, and more than double DC’s highest minimum parking requirement for apartment buildings.

by Tom on Aug 15, 2008 2:31 pm • link • report