Note: Some may have seen that AZA and TMT have been playing “I post, you post” in the comment threads following somewhat unrelated posts concerning the parameters of functional density of Alpha Communities and how these densities relate to the Beta Community of Reston.In response to TMT’s latest note I have tried to put these perspectives – clarified and updated – together in one place. I asked Prof. Risse to post it and welcomed him to edit and add notes from his perspective. Since this is all about human settlement patterns, I also asked him to alert those that review comments for violations of The Litmus Test to be especially watchful of unfounded Idea Spam and Intentional Information Sabotage.AZA


Following the post by Mr. Bacon on school reform, I noted:

Only when there are densities of around 30 persons per acre at the Alpha Community scale can there be efficient and effective transport alternatives that enable students to choose different educational options.

This statement is based on our understanding of the transformations that reflect 1) the end of the era of the ‘Autonomobile’ domination of settlement patterns, 2) the end of vast subsidies for dysfunctional settlement patterns, and 3) the changes in citizen settlement pattern preferences noted below.

In a later comment, TMT noted that “30 persons per acre” seemed high to him. (Most of the dialogue from his comment and my response is summarized below.)

I responded to the reference to “30 persons per acre” by noting that the original statement was “30 persons per acre AT THE ALPHA COMMUNITY SCALE.” I suggested that without a spacial quantifier, a statement on density is a meaningless abstraction. This is NOT just nit picking. Density must always be expressed in terms of quantity per some measure of area that has a specific definition.

TMT said: “I don’t think this level of density is politically feasible except in selected locations.” Read more.

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  1. TooManyTaxes Avatar

    I will try again.
    I agree with the concept of balance between jobs, housing options and public facilities (infrastructure) — my term. Such a community is more likely not to need extensive investments in transportation infrastructure than would a community that was not balanced in terms of jobs and housing options. I don’t believe, however, that the availability of jobs and their types can be easily controlled by government decision makers.
    I think the key controllable factor is public facilities. Government entities, even in Dillon Rule Virginia, have significant ability to match growth with added public facilities – but generally will not do so.

    Local governments in Virginia tend to prefer commercial development over residential because the former generates more tax revenue than it demands in services. And vice versa for residential development. However, this conclusion does not, IMO, address the need for additional and very expensive transportation facilities to bring workers to and from the commercial center — witness BRAC in southern Fairfax County.
    Let’s talk about density. As Gerry Connolly would say, “Density is neither good nor bad in an of itself. It all depends on whether there is sufficient public facilities.” I agree with Mr. Connolly on this point. However, I submit that adequate public facilities rarely come with the additional development. Thus, most people in NoVA and especially in Fairfax County are likely to see development as a negative because the lack of necessary infrastructure causes a degradation in the quality of life and usually, higher taxes as elected officials try to play catch up.
    So that is why, IMO, the typical resident of Fairfax County would likely think that the county is about built out, even with an average density per acre of 4.2 (January 2010 – pre-census). Taking density to 13 per acre (as per the Reston cap) would likely drive down the quality of life substantially and real estate taxes upward. I would readily concede from a theoretical basis, that it would be possible to add sufficient infrastructure that 13.0 density would not seem like hell on earth. But it may not be politically and economically feasible to build such infrastructure.
    I submit that an overwhelming majority of Fairfax County residents would be ready to take up arms if a developer, an expert, an elected official or anyone else even suggested going to 30 people per acre. They would likely see such growth as all negative and no positive.
    A person who said, this level of development would prevent sprawl would likely be answered with “We want sprawl to keep our community livable.” Richard Florida would be laughed or threatened off the podium were he to speak.
    Stewart Schwartz tried to make these arguments in connection with the final planning process for Tysons. But he and others were simply unable to address the transportation studies submitted to VDOT as part of the 527 process. “Trust me, this will work” just will not trump a 527 traffic study that shows “Going from 46 M. sq. ft. to 84 M. sq. ft. will result in total gridlock.”
    Bottom Line — the lack of adequate public facilities found with development in NoVA will create a political climate where it will be difficult to achieve major increases in density except in selected locations. This statement is not intended to disparage any one’s theories, studies or research.


  2. LarryG Avatar

    not seeing any comments here yet…………..

  3. Nice disclaimer. Too bad it has come to that. My stuff got zapped, even though It was not derogatory. All i did was ask a few pointed questions.

  4. EMR – I think we will always be two ships passing in the night. I am where I am on infrastructure after about 5 years of working on Tysons Corner redevelopment; talking with developers, county and state officials and employees. I have also dealt with utility construction issues for about 30 years plus.

    There clearly is some advantage for building infrastructure in dense urban locations. It would be much less expensive, for example, to build pipes to serve 100,000 people in Washington, D.C. than to serve 100,000 in Washington County, MD. It would be much less expensive to operate bus service in Fairfax County to serve 1000 people than it would be to operate bus service in and around Fairfax, Minnesota. Do we agree on this?

    But it often takes a lot less infrastructure to build houses outside the clear edge from empty fields than it would be to build condos or apartments in a dense urban area. You just don’t need the same amount of things in outlying areas as you in urban areas. Land and construction costs are much higher in urban areas.

    Take a look at Table 7 in the new Tysons Comp Plan. The price tag is at least $1.7 billion. Based on my knowlege and experience, I just don’t see that sprawl comes with a $17 billion price tag as does Tysons.


  5. EMR – I think it is time for us to agree to disagree on infrastructure costs. I think my position, which does not disagree with yours in all circumstances, is reasonably correct.
    The costs for Table 7 of the new Comp Plan for Tysons are probably understated. We’ve seen costs skyrocket for Dulles Rail, and the HOT lanes costs are higher than originally projected.
    I also believe a push to increase density in Reston above an average of 13 persons per acre will be strongly resisted and no one would accept 30 persons per acre except in TOD locations, and then with many conditions. I don’t think Fairfax County officials would vote for those levels of density either. For example, Sharon Bulova has indicated on a number of occasions that she feels urban growth should be restricted to a few chosen sites and the suburban lifestyle in other areas needs to be protected.
    But if we all agreed on everything, this blog would be very dull.

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