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1、REPORT|May 2021TR ANSPORTATION SOLUTIONS FORCONGESTED“BOOMTOWN”CITIESConnor HarrisFellowTransportation Solutions for Congested“Boomtown”CitiesAbout the AuthorConnor Harris is a fellow at the Manhattan Institute,where he focuses on infrastructure,transportation,and housing policy.His writing has appe
2、ared in publications such as City Journal,the New York Post,and the Harvard Political Review.Harris graduated from Harvard University in2016 with a B.A.in mathematics and physics.2ContentsExecutive Summary.4Introduction.5Freeway Expansions and Light Rail:Expensiveand Inefcient.5Four Ways to Improve
3、Transportation.6Case Studies.8Conclusion.14Endnotes.153Transportation Solutions for Congested“Boomtown”CitiesExecutive SummarySeveral citiesespecially in the South and Southwesthave seen signicant population growth recently,in partas a result of the Covid-19 pandemic.These“boomtowns,”such as Atlanta
4、 and Dallas,typically have weak masstransit and near-universal car dependency and therefore face signicant challenges in expanding transportationcapacity.Even with continued growth,they will not be dense enough to support large-scale mass transit.Noris expanding freeways an easy solution because oft
5、en the most congested roads are in traditional downtowns,where the cost of expansion is highest.Older urban freeways typically have little marginal land to allow expan-sion,and dense development nearby makes eminent domain expensive and politically controversial.Some sprawling metropolitan areas hav
6、e insteador,in some cases,alsobuilt extensive light rail systems,hoping to entice drivers out of their cars.But light rail systems often have very low ridership,and many trips takeas long or longer than they would with a car.In this report,I will discuss four other ways that boomtown cities can impr
7、ove transportation capacity:simpleimprovements to surface road networks,rationalizing public transit networks,introducing market mechanismsto road trac,and urban design.Then I will present ve case studies of the current transportation infrastruc-ture,as well as recommendations for future improvement
8、,in DallasFt.Worth,Texas;Austin,Texas;Atlanta,Georgia;Tampa,Florida and Denver,Colorado.TR ANSPORTATION SOLUTIONS FORCONGESTED“BOOMTOWN”CITIESIntroductionThe COVID-19 pandemic has accelerated population growth in“boomtown”cities,such as Atlanta and Dallas.These cities,many of which are in the South
9、and Southwest,typically share a few distinguishing characteristics.They have weak mass transit and near-universal car dependency.They also have almost exclusive single-familyhousing,with new housing growth coming about via horizontal expansion,with limited redevelopment of denserareas.And employment
10、 is dispersed,with many jobs in legacy downtown areas but the majority of jobs,evenwhite-collar ones,in other“edge city”developments.For these reasons,boomtown cities face a transportation challenge:they are too low-density for viable large-scale mass transit,and will remain so for decades,even if a
11、ll future population growth occurs in already built-upareas.But the other option,expanding freeways,presents its own challenges.The most congested freeways arethose in traditional downtowns,which are still typically the densest areas with the largest job clusters,and adisproportionate share of trips
12、 from one point in a metro area to another will pass through or near city centersas a matter of pure geometry.These freeways are therefore most in need of expansion but are also the mostdicult to upgrade.Older urban freeways typically have little marginal land to allow expansion,and dense de-velopme
13、nt nearby makes eminent domain expensive and politically controversial.Adding to the diculty isthat many near-downtown areas in cities have seen substantial revitalization driven by increased preference forurban living,so disrupting these areas with new freeway construction is both expensive and und
14、esirable.Most urban economies confronting these challenges decentralize,sending job growth from central to peripheralareasa shift in economic geography that can harm low-income workers.Most metropolitan areas have strongeconomic segregation,with wealthy suburbs clustered in a“favored quarter”on the
15、same side of the city center.1Areas in the favored quarter are thus less accessible than city-center jobs for working-class residents in otherresidential areasespecially for transit-dependent residents.How have local political leaders,activists,and transportation departments handled this challenge?S
16、ave for a fewnotable exceptions,with one of two approaches:unimaginative freeway expansion;or building new mass transit,usually light rail,in the hope of luring residents out of their cars.Both approaches should be critically examined.Freeway Expansions and Light Rail:Expensive and InecientMany fast
17、-growing cities have invested in large freeway expansions.These can be loosely separated into twotypes:peripheral and center-city.Peripheral freeway expansions are in lower-density areas,typically reuse landalready owned by local departments of transportation,and are relatively cheap.Center-city fre
18、eway expansions are more important and more dicult.Even in areas with widely dispersed em-ployment,traditional downtowns are still important job centers,and a large fraction of trips between dierentpoints in the metropolitan area must pass through or near them.But downtown freeway expansions tend to
19、be very expensive because land values in downtowns are high and expansions often require demolishing exist-5Transportation Solutions for Congested“Boomtown”Citiesing structures.Also,interchanges near city centers are that prevail in many sprawling cities.Therefore,al-often structurally complex.For e
20、xample,an expansion though rail lines are superior at serving short-distanceof just a few miles of Austins I-35 freeway through travel within dense areas of development,they are infe-downtown is projected to cost$8 billion;a realignment rior for the use to which they are frequently puttravelof Inter
21、state 10 in Houston,likewise,is estimated at from distant suburbs.This is especially true if,as is$7 billion and will require the displacement of several commonly the case,light rail stations are surroundedthousand residents.by parking rather than by dense buildings:if you haveto drive to get to the
22、 station anyway,driving all the waySome sprawling metropolitan areas have insteador,is almost always faster.in some cases,alsobuilt extensive light rail systems,hoping to entice drivers out of their cars.Dallas,forinstance,is a poster child for suburban sprawl;yet ithas a 93-mile light rail system c
23、onnecting the city andmany of its suburbs(almost as long as Chicagos L).TransportationMost of these light rail systems see extremely low rid-Four Ways to Improveership:Dallas Area Rapid Transit(DART),for instance,saw only about 1,000 average weekday riders per mile There are better methods for impro
24、ving transportationof system length in 2019less than one-fourth the rid-in low-density cities.We will address four methodsership of San Franciscos Muni light rail system,which simple improvements to surface road networks,ratio-serves a much more built-up area.2nalizing public transit networks,introd
25、ucing marketmechanisms to road trac,and urban designwhichLight rail planners are incentivized to choose routes vary considerably in how much political controversythat will produce little opposition from local resi-they are likely to cause.dentsbut this often means routes that have few localresidents
26、 along them.This often guarantees low rider-First,many relatively simple improvements to surfaceship because the time and hassle of driving a car to a road networks can be done for relatively low capitaltransit stop seldom justify not simply driving the whole expenditures and without demolishing bui
27、ldings orway.Light rail planners also overvalue destinations harming the pedestrian environment.For example,such as airports,which appeal to the public out of pro-optimizing trac signal timing can improve trac owportion to their need for transitmany people think on arterial roads considerably,includ
28、ing reductions ofthat a train to the airport is a nice idea,even if they 10%or more in fuel consumption.One optimizationend up using it rarely,if at all.Furthermore,the struc-project in California estimated a benet-to-cost ratioture of many regional public transit authorities gives of 58:1.4 Convert
29、ing ordinary intersections to round-suburban municipalities disproportionate inuence;abouts also carries substantial benets in reducingthey tend to demand long,uneconomical routes into delays as well as accidents,at least for those intersec-car-oriented suburbs.Finally,planners often assume tions wi
30、thout a single dominant direction for tracthat stations in suburban areas will generate“tran-ow.5sit-oriented development”that can serve as a source ofriders,but the actual ridership in far-ung transit-ori-Second,boomtown cities should also consider rational-ented developments is typically disappoin
31、ting.izing their public transit networks.Many Sunbelt citieshave sparse bus networks whose individual routes areDallas provides excellent examples of all these ten-quite meandering,in an attempt to have each individu-dencies.The DART board is heavily dominated by al bus route connect as many destina
32、tions as possible.suburban interests that tend to demand investments Attempts to change these routes can engender opposi-to distant areas with residents who will not actually tion from the small but vocal constituencies that enjoyuse the system;3 DARTs least used stations,further-one-seat rides,but
33、bus routes that run on a regularmore,were built at speculative transit-oriented devel-grid pattern can cover far more territory and oeropmentsat which ridership typically stayed stagnant faster trips to a greater variety of destinations.Goingor even dropped somewhat after the development was from an
34、y point on the service area to any other,in thecomplete.DARTs lowest-ridership lines are the ones ideal case,would require transferring only onceandthat serve the two principal Dallas airportsand,to grid systems can often use fewer dierent routes to getreach the airports,they run through several mil
35、es of the same coverage as more amorphous bus systems,unwalkable industrial parks and distribution centers.thereby allowing greater frequency on each route.Asan added bonus,grid systems with one bus line follow-The average speed of light rail lines is far less than that ing each major street are eas
36、ier to commit to memory.of freeways,even under the conditions of congestion This approach to rationalizing bus networks has been6advocated perhaps most forcefully by Jarrett Walker,Toll lanes have advantages,even for those who do nota prominent Portland-based transportation consultant use them,and t
37、he typical tolla few dollarsis quiteand a leading advocate for the benets of regular grid aordable even to the working class.First,they providenetwork designs.6reliable paths for mass transit,especially long-distancecommuter bus services,allowing bus systems to beThird,there are more controversial a
38、pproaches that scheduled far more reliably and with less redundancy.involve introducing market mechanisms to road trac.Second,they can increase freeway capacity dramati-Most roads in the U.S.,including most freeways,are cally by providing a lane that is always guaranteed tountolled.Driving imposes c
39、osts on those besides the be operating at maximum capacity.When a freewaydriver.First,of course,there are the costs of pollution gets congested,it is not only travel speeds that declinefrom the combustion of gasoline as well as less recog-but also throughput in vehicles per second.By movingnized sou
40、rces such as microplastics from tire erosion.even a small fraction of vehicles o the open lanes ofSecond:every driver imposes costs on every other by the freeway,therefore,additional uncongested tolledmaking their journeys slower and more dangerous.lanes can provide far greater increases in rush-hou
41、r ca-These costs may be trivial for drivers joining a nearly pacity and less congestion even in the untolled lanes.8empty road,but they rise considerably as trac on theroad grows:the vehicle that serves as the straw that Toll lanes can be protable and thus built and nancedbreaks the camels back and
42、turns heavy but free-ow-entirely from toll revenues,including by private con-ing trac into a trac jam may cost tens or hundreds tractorsthereby insulating the public from the risksof thousands of dollars worth of others time.of construction cost overruns.Though express lanesare often built in the co
43、urse of regular freeway widen-The classic economic solution to externalities like these ings,they can also be built as elevated structures withis Pigouvian taxes,which place a surcharge on exter-support pillars placed in freeway medians,allowingnality-generating activities equal to the cost of the e
44、x-their construction without any additional consumptionternalities themselves.With a Pigouvian tax in place,of land at the margins of the existing freeway.Somethe only people who will do externality-causing activi-cities have even experimented with tolled“queue-jump-ties are those for whom the priva
45、te prots of the activ-ers”at arterial intersectionsshort tunnels or yoversity exceed the public costs.Driving is already taxed to that allow trac in some arterial lanes to go over orsome degree,but in a way that does not correspond to under the intersections and that can be built within thethe exter
46、nalities.Federal and state gasoline taxes are existing right of way.9the same whether one drives on an urban road that isnear or over capacity(and near large populations af-Finally,the fourth possible type of solution lies in thefected by air pollution)or a rural one with plenty of ca-realm of urban
47、 designaltering building and zoningpacity to spare.Far closer to the economic ideal would codes to allow more people to live closer to major jobbe road tolls that vary based on time of day,charging centers.Such reforms will not render entire cities ac-higher prices at rush hours and loweror even no
48、cessible without a car:the gap between current popu-tolls at slack times.Such variable pricing would keep lation densities and those that allow large-scale massfreeways running faster and at higher capacity.transit is far too large.But liberal land use can go a longway toward making at least portion
49、s of cities relativelyIn general,converting existing roads into tolled roads accessible without a car.is politically toxic,and the Interstate Highway Actgenerally prohibits tolls from being charged on most Consider Houston,whose regulatory environment forinterstate freeway segments built with partia
50、l federal redevelopment of residential areas is likely the friend-support.7 One approach gets around these problems:liest of any large U.S.city.It has no formal zoning codeinstead of tolling existing highways,toll lanes(or that designates land for only certain economic uses,“managed express”lanes)ca