La vostra casa: come il mulino bianco?

Un aspetto significativo della sostenibilità dei trasporti riguarda la destinazione d’uso del territorio. E in merito a ciò quale decisione più importante di quella della scelta del posto di dove abitare, il posto nel quale iniziano e finiscono la maggior parte dei nostri spostamenti quotidiani? In questo articolo Todd Litman del Victoria Transport Policy Institute ci illumina saggiamente sulle rivendiazioni della Smart Growth (crescita intelligente) in Nord America, ma l’analisi che effettua si potrebbe applicare ovunque, almeno nei paesi industrializzati.

Dove vogliamo stare: le scelte abitative e le loro conseguenze.

La Smart Growth consiste in insediamenti abitativi più compatti, accessibili e serviti da una rete multimodale di trasporti. Questo può portare numerosi vantaggi ai residenti di queste aree e alla società nel suo complesso. Gli oppositori di questo concetto sostengono che la maggior parte dei consumatori non amano questo tipo di organizzazione e così vengono danneggiati dalle politiche che li incoraggiano. Questa analisi suggerisce altre conclusioni.

Benché le indagini di mercato indichino che la maggior parte delle famiglie nord americane preferiscano villette monofamigliari, registrano anche una forte e continua tendenza nelle preferenze dei consumatori verso quelle caratteristiche della Smart Growth come l’accesibilità e la pluralità di scelte nei trasporti (intese come una maggior possibilità di spostamenti pendolari brevi e di presenza di servizi nel raggio di una distanza percorribile a piedi dalla propria abitazione). Vent’anni fa solo un terzo dei nuclei famigliari mostrava preferenza per la Smart Growth, ma si prevede che questa percentuale cresca fino ai due terzi entro i prossimi due decenni.

Questa è la conseguenza di diversi trend demografici ed economici, tra i quali l’invecchiamento della popolazione, l’aumento dei costi dei carburanti e la maggior preoccupazione rispetto alle tematiche ambientali e sanitarie. Inoltre gli stili di vita suburbani e l’utilizzo massiccio dell’automobile che implicano sono sempre meno “glamour”. Una percentuale sempre più alta di consumatori aspira oggi a vivere in un ambiente urbano per almeno una parte della propria vita, e il mercato immobiliare nel 2008 ha registrato una netta caduta negli investimenti immobiliari nelle periferie. Le famiglie del futuro probabilmente saranno più razionali e prudenti.

Detta in maniera diversa, per alcuni decenni le scelte abitative e di trasporto dei consumatori sono apparse come noncuranti delle regole di base dell’economia. La scelta del posto dove collocare la propria abitazione sembrava insensibile ai costi legati alla distanza dal posto di lavoro e ai prezzi del petrolio, concretizzandosi in stili di vita autodipendenti e insediamenti abitativi molto rarefatti. Gli spostamenti e piedi, in bicicletta e con i mezzi pubblici venivano abbandonati e considerati come poco desiderabili e inferiori, anche quando si mostravano efficienti ed economici. Il crescere del traffico, i prezzi dei carburanti, i problemi di salute pubblica e ambientali hanno indotto i consumatori a comportarsi più razionalmente. Alcuni abbracciano queste nuove opportunità, altri reagiscono con timore.

Questo non significa che i viaggi in automobile e la vita nei complessi residenziali suburbani finiranno. Anche con politiche di smart growth molto aggressive la maggior parte dei Nordamericani continueranno a vivere in case monofamigliari, anche se in una percentuale sempre più alta saranno costruite su lotti di terreno piccoli, a schiera, come nelle abitazioni di città.

Comunque, la domanda di nuove abitazioni cambierà radicalmente. L’attuale disponibilità di case monofamigliari su grandi lotti di terreno in aree suburbane eccede ampiamente la domanda, causando un crollo dei prezzi e un aumento dei fallimenti. Nel migliore dei casi occoreranno anni per alcune abitazioni per ritornare ai valori di mercato del 2005 in termini reali, corretti in base all’inflazione. Molto più probabilmente la domanda per questo genere di alloggi non ritornerà più ai livelli precedenti.

D’altra parte il mercato per alloggi a schiera in insediamenti accessibili e multimodali è molto forte. Questo genere di abitazioni ha mantenuto il suo valore e si prevede che la domanda aumenti significativamente in futuro a causa di trend demografici ed economici strutturali. Progettisti e comunità che sapranno cogliere queste variazioni del mercato potranno avere successo. Quelli che continueranno con le politiche passate hanno grosse probabilità di fallire miseramente.

Questa nel complesso è una buona notizia, visto che gli insediamenti multimodali, compatti e accessibili possono essere di gran giovamento per i consumatori e la società, garantendo una maggior efficienza e un più ampio spettro di scelte.

I residenti delle zone “Smart Growth” beneficiano direttamente dei risparmi di tempo e di denaro, oltre che dal miglioramento della salute e della sicurezza. La società risparmia sui costi per le infrastrutture e riesce a garantire migliori opportunità per i gruppi più svantaggiati e una migliore qualità dell’ambiente.

L’opinione che la Smart Growth priverebbe i consumatori delle scelte di abitazione preferite è chiaramente inaccurata. Gli insediamenti suburbani sono oggi disponibili in abbondanza e prezzi scontati, mentre quelli con caratteristiche di Smart Growth sono scarsi in molte zone, il che fa aumentare i prezzi, rendendoli inaccessibili alle famiglie a basso reddito che sono quelle che più ne avrebbero bisogno. La suburbanizzazione selvaggia è il risultato, in parte, di distorsioni nella progettazione urbana e nel mercato che hanno favorito gli insediamenti a bassa densità abitativa e gli spostamenti in automobile.

Ci sono molti motivi che ci dovrebbero spingere a correggere queste distorsioni per favorire la crescita intelligente. Queste riforme dovrebbero riguardare gli schemi di utilizzo dei terreni edificabili che riflettano meglio le preferenze dei consumatori

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* L’articolo dal quale è stato tratto il presente riassunto si trova su http://www.vtpi.org/sgcp.pdf (36 pp.)

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Todd Litman è fodatore e direttore del Victoria Transport Policy Institute, un’organizzazione indipendente di ricerca dedicata allo sviluppo di soluzioni innovative per i trasporti. Il suo lavoro aiuta ad ampliare lo spettro di scelte e di campi di intervento della progettazione dei trasporti, a migliorare le tecniche di valutazione e a divulgare concetti tecnici di ambito specialistico. Lo potete trovare in: 1250 Rudlin Street, Victoria, BC, V8V 3R7, Canada. Email: litman@vtpi.org. Phone & Fax: +1 250-360-1560

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