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1、ContentsExecutive Summary4Introduction 5Freeway Expansions and Light Rail: Expensive and Inefficient5Four Ways to Improve Transportation6Case Studies8Conclusion 14Endnotes 15Transportation Solutions for Congested uBoomtownn Citiesas MARTAdespite the systems limited extent- does offer good access to
2、the regions largest job clusters. Such measures could not end car dependence, of course, but they could redirect some of the regions population growth into areas that generate fewer car trips.Denver Colorado CURRENT STATUSDenver, like Austin, has seen a massive growth in tech-sector employment, than
3、ks to the proximity of the University of Colorado in nearby Boulder and because of tech workers from elsewhere drawn by an outdoor lifestyle facilitated by the nearby Rocky Mountains and by a relatively low (though quickly rising) cost of living compared with coastal urban areas such as New York and
4、 San Francisco. Unlike the other case studies, the Denver region (as well as nearby Boulder, a university town and another tech industry cluster about 24 miles to the northwest) has “urban growth boundariesthat limit the expansion of the areas built footprintsa limitation scarcely alleviated by urba
5、n zoning laws, which impose strict caps on density.Freeways in Denver are often congested. The most congested freeways are Interstate 25, which connects downtown to the areas to the north and south and carries longer-range traffic to Wyoming and New Mexico; and Interstate 270, which provides a bypas
6、s route for traffic going from north to east of downtown Denver. Interstate 70, a main connection to the eastern suburbs, is notably congested but less so than I-25. Some freeways have managed express lanes: I-25 north of downtown, one segment of the E-470 peripheral highway, and US-36, which connec
7、ts Denver to Boulder.28 (The managed express lanes on US-36 host a popular bus rapid transit service called the Flatiron Flyer, which runs half-hourly and travels from Denver to Boulder in just 51 minutes.)The Denver region has an extensive network of light rail and commuter rail, most of it converg
8、ing on downtown, but it receives generally low ridership. As urban-planning writer Christof Spieler has pointed out, the Denver rail system was focused on attracting “choice” riders who would otherwise be making city- to-suburb trips in cars. Denver-area rail lines, Spieler notes, typically follow e
9、asy alignments, sometimes being built in freeway medians as part of freeway expansion projects, that run vaguely near important destinations such as medical centers but are impractical to reach by foot.29 Some light rail lines have been built to serve exurban transit-oriented developments that are n
10、ot yet near completion. Meanwhile, large amounts of accessible downtown land are wasted on low-value uses, such as the surface parking lot for a stadium that takes up dozens of acres of land near two central light rail stops. WHAT IS BEING PLANNED?There is a planned upgrade to the central segments o
11、f Interstate 70. This project, called the Central 70 Project, will reconstruct much of the freeway, add one tolled express lane in each direction, and make other improvements, such as lowering part of the freeway below-grade and capping it with a park.30Denvers Regional Transportation District plans
12、 three expansions of commuter or light rail, mostly focused on suburban areas. The Southwest Extension of the B Line, in planning since 2008, will extend a light rail line 2.5 miles to Highlands Ranch, a low-density residential and commercial development just outside the peripheral C-470 highway; th
13、e new terminal station will include 1,000 parking spaces.31 An extension of a northwestern commuter rail stub line to Boulder, along a route largely redundant with the existing Flatiron Flyer, is also planned. The only central expansion is a 0.8-mile extension of the near-downtown L light rail line.
14、32 A long-planned bus rapid transit line will improve bus service on the Colfax Corridor, an important commercial artery whose existing bus gets more ridership than most of the citys rail lines. WHAT SHOULD BE DONE INSTEAD?The L Line expansion may be viable, but further exurban rail expansions are a
15、 bad idea. The existing suburban trains already get very low ridership, and there is no reason to double down on failure. A train from Denver to Bouldera long-term goal of local transit plannersis redundant with a currently very successful bus rapid transit project. A higher-speed regional rail line
16、 could become economical if ridership demand on the corridor increases drasticallyto the point that the lower operational costs per passenger of rail outweigh the cheaper capital costs of bus service, especially as a reasonably direct rail line between the two cities already exists. But such a chang
17、e would nevertheless likely require considerable infrastructure investment and should not be embarked on without clear signs of passenger demand.As always, Denver should clear out all obstacles toward building more housing and commercial buildings downtownespecially in areas currently used for parki
18、ng and low-value industry (Denver has substantial exclusive industrial zones in areas relatively close to downtown.) The inclusion of toll lanes in the Central 70 Project is well considered, and future highway projectsin the area should prioritize extending the existing toll lanes to a continuous ne
19、tworkespecially on other severely congested freeways such as Interstate 270.Tampa9 Florida CURRENT STATUSThe Tampa metropolitan area can be divided into two parts: Hillsborough County, which lies on the east side of Tampa Bay and contains Tampa itself; and Pinellas County, on the peninsula that boun
20、ds Tampa Bay to the west and whose principal cities are Clearwater and Saint Petersburg. (Tampas northern exurbs sprawl across the border into Pasco County.) The main freeway through Tampa and Saint Petersburg is Interstate 275, which connects Tampa to its northern suburbs and is typically moderatel
21、y congested near downtown. The Lee Selmon Expressway connects Tampa with its eastern suburbs and has virtually no congestionthanks largely to a three-lane viaduct built in the freeway median that carries tolled traffic in the peak direction; it was built by a private operator at no financial risk to
22、 the public.Tampa is the only one of these five cities without substantial rail transit: a preserved 2.7-MILE streetcar line running historic rolling stock acts only as a circulator for the downtown and an adjacent historic neighborhood. The rest of Tampas transportation is handled by bus. Hillsboro
23、ugh Countys transit authority runs a largely coherent bus grid with lines along arterials downtown and in the denser neighborhoods to the north and west. WHAT IS BEING PLANNED?On the transit side, there are no plans for substantial light rail investments. A planned intercounty light rail line mooted
24、 for much of the 2010s was scrapped in 2018, replaced by a plan for rapid buses.33 (Few buses run through from Pinellas to Hillsborough County, and none runs between urban centers at a speed sufficient to compete with driving a private car.) According to current plans, a bus rapid transit line will
25、run mostly on I-275, in new dedicated lanes in the freeway median. Stations would also be built on the freeway median so that the bus would not have to exit. The project would cost $353 million for an estimated 5,400 riders per dayquite a high cost per projected rider for a bus lineand would not be
26、complete for another decade.34Several freeway widenings are planned for the Tampa area. Floridas Department of Transportation has a wide-ranging plan to improve capacity on the regions freeways, including almost 100 new miles on toll lanes on all freeway segments being rebuilt, the exception being a
27、 segment of Interstate 275 north of downtown Tampaperversely, one of the most congested segments in the entire network.35 Expansion of this segment of I-275, especially with toll lanes, provoked severe neighborhood opposition, largely because widenings would be destructive to many lower-income, heav
28、ily racial minority communities.36 One earlier freeway plan was estimated in 2016 to cost $6 billion for 90 miles of freeway upgrades.37 WHAT SHOULD BE DONE INSTEAD?Tampa is one city in which light rail investments might have made sense in the abstract. The long crossings of Tampa Bay between Hillsb
29、orough and Pinellas Counties serve as natural chokepoints, and chokepoints speak in favor of high-capacity transportation options. It would have been prudent to have left space for possible rail transit when building the crossings. However, given that the current bridges are road-only and provide no
30、 room to add a rail deck, rail construction is likely uneconomical. Expansion of light rail within downtown Tampa itself may be worth considering: some near-downtown areassuch as the areas just north of downtown along Tampa Street and Florida Avenuehave seen substantial amounts of new mid- and high-
31、rise residential development. As always, additional infill development near existing urban centers in downtown Tampa would aid this goal.Bus rapid transit along 1-275, in order to fill a gap in current bus service between the metropolitan areas major centers, is a good idea, but improvements to such
32、 service shouldnt have to wait until the completion of a dedicated lane. And the lines low ridership projections ought to bring into question whether hundreds of millions of dollars in capital expenditures on dedicated lanes and stations are worthwhile. As an interim measure and to test transit dema
33、nd, the Tampa areas mass-transit providers could start running express buses now between the areas major centers, especially downtown Tampa and Saint Petersburg, without waiting for upgrades.The focus on toll lanes in new freeway widenings is good, but in many casesespecially I-275 near downtown Tam
34、paconcerns about community impacts have validity. It may be worth investigating whether it would be feasible from an engineering standpoint to place new toll lanes in an elevated structure instead, on the model of the Lee Selmon Expressway. Such a plan would have visual impacts but would not damage
35、the neighborhood fabric nearly as much.Transportation Solutions for Congested uBoomtownn CitiesConclusionThe transit situation in these five boomtown cities suggests a few key policy recommendations. First, new toll lanes should be preferred to brute-force and less effective expansions of untolled f
36、reeways, especially in areas with expensive land. Second, new rail transit expansions should be treated with extreme skepticism, especially when they are built to serve future, not present, development. Third, we should liberalize zoning in areas with high demand where more growth will place fewer s
37、trains on the outlying road network, especially near downtown areas.One overarching principle is in play here: land-use and transportation planning work best when they are tied most closely to actual demandand this means, above all, trusting market mechanisms. Financing new road construction out of
38、tolls, for example, naturally balances the costs and benefits of new construction. The most beneficial new road projects are those that people would be willing to pay tolls to use. Similarly, since people naturally want to live near job opportunities, relaxing zoning to allow more construction near
39、job centers can relieve strain on the transportation network from long-distance commutes. Conversely, blind expansions of underused mass transit roads or overly congested roadswhose congestion is frequently the consequence of irrational road tolling schemestend to be poorly targeted.To close, here i
40、s a brief list of suggestions that state and federal policymakers can use to improve transit decisions and land-use planning.Repeal restrictions on tolling existing roads. Prohibition of tolls on interstate highways has not only led to severe freeway overcrowding; it has suppressed market indication
41、s of investments in new road capacity and led to situations in which, for example, direct freeways are free but longer detours cost money. Moreover, as cars become more fuel-efficient in the next several yearsand the stock of electric and other non-gasoline-consuming vehicles increasessole reliance
42、on the gasoline tax as a source of highway funding is likely to lead to shortfalls.Tie mass-transit funding decisions to existing density. Many bad investments in rail transitrecent DART expansions are exampleshave been based on drastically inflated estimates of ridership. These estimates often depe
43、nd on unrealistic estimates of the number of riders that will be provided by new development along the route. At least on a relatively crude systemwide level, furthermore, it is possible to estimate the ridership of transit systems relatively well simply by observing the number of jobs and residents
44、 within walking distance of the stations. State and federal government agencies that provide money to fund transit expansions should consider tying funding decisions to existing development patternsand only funding new systems or lines in areas with sufficient existing population and job density.Con
45、sider state zoning preemption laws near transit and large job clusters. In California, a state with a severe housing shortage in its urban areas, the state has repeatedly come close to passing significant housing liberalization in areas near transit stops. Though Sunbelt cities do not have housing c
46、rises on the scale of Californias, many of themespecially Austin and Denverhave seen significantly increased housing prices, especially in central areas near downtown. These areas often have the strongest entrenched lobbies for housing shortages: affluent single-family homeowners in desirable areas
47、who have received windfall profits from restrictive zoning. Local zoning debateswhich typically give incumbent homeowners outsize influenceprivilege them. But the best interests of cities as a whole are likely better served by removing these zoning decisions to the state levelwhere officials can rec
48、ognize that liberal development in downtowns can help increase urban areas5 economic productivity and reduce the need for additional spending on exurban infrastructure.EndnotesSheryll Cashin, Localism, Self-Interest, and the Tyranny of the Favored Quarte匚 Addressing the Barriers to New Regionalism,
49、Georgetown Law Journal 88, no. 7 (July 2000): 1985-2048.1 American Public Transportation Association (APTA), Public Transportation Ridership Report, Fourth Quarter 2019, Feb. 27, 2020.2 Jim Schutze, Dallas Needs to Do a Tammy Wynette on DARTD-I-V-O-R-C-E,M Dallas Observer, Feb. 13, 2020.3 Sam Staley and Adrian Moore, Mobility F/rsf (Lanham, MD: Rowman & Littlefield, 2009), p. 146.4 Washington State Dept. of Transportation,