Growing awareness of the importance of sustainable, resilient communities is encouraging.

There is a lack of attention, however, to one of the most compelling sustainability challenges facing Hawaii today: land transportation.

The present land transportation system — a network of highways primarily supporting single-occupancy vehicles (SOVs) — is unsustainable. Each year Hawaii consumes over 400 million gallons in liquid fuels for land transportation. If imported fossil fuels stopped coming, our economy and lifestyle would collapse.

The question is: How can we achieve a sustainable, resilient land transportation system — especially with declining federal funds?

On Kauai, we have clearly outgrown the state highway system of mainly two-lane roads. We need to expand its capacity.

Widening existing highways and building bypasses — the conventional wisdom — will not work for several reasons:

» It is not sustainable. The single occupancy vehicle is the most inefficient and wasteful land transportation mode (based on fossil fuel use, land use and greenhouse gases).

» Even if we forgo sustainability, we don’t have the money to finance "business as usual." It is costing $80 million to widen two miles of highway on Kauai between Lihue town and Kauai Community College. According to the Hawaii Department of Transportation (HIDOT), Kauai will be lucky to get $600 million in federal funds over the next 20 years — enough to widen only a fraction of existing highways.

» Adding lanes or bypasses won’t meet all our community’s future mobility needs. By 2035, 30 percent of Kauai’s population will be 60 and older. The elderly, young, disabled and those who cannot afford a car — over half the population — will not be optimally served by simply adding lanes or bypasses.

What’s the answer? Mode shift and compact mixed use.

To expand our existing highway capacity, we need to shift the travel mode that most people choose each day from SOV to transit, walking or biking. Mode shift increases the highway system’s capacity by making other modes more easily available, safer and user-friendly.

For example, if 40 people at Lihue Airport wanted to travel 8 miles to Kapaa, the highway capacity needed to move them varies dramatically based on travel mode chosen: 40 people each using a car for the 8 miles computes to 320 vehicle miles traveled (40 cars x 8 miles); whereas 40 people all in a single bus computes to 8 vehicle miles traveled (one bus x 8 miles). Vehicle miles traveled is the key measure of highway capacity needed (correlating with fuel usage and greenhouse gas generation).

"Compact mixed use," a smart growth concept, reduces highway use — e.g., affordable workforce housing near work centers lessens highway usage while making walking and biking to work more possible.

Kauai County’s Multimodal Land Transportation Plan aims to increase bus ridership over the next 20 years by 1,000 percent. This is achievable. Bus demand presently exceeds services available. We don’t have to convince people to ride the bus; we just need to expand services.

However, the county cannot achieve its goal without HIDOT support. State highways must be transit-friendly (sheltered bus stops, turn-off lanes, carpool lanes) include bikeways and provide sidewalks through towns.

Given scarce resources, HIDOT’s long-range plan for Kauai highways must strategically address all travel modes. Yet, the urgent need for improved transit service is unaddressed in a recent draft.

Gov. Neil Abercrombie has proclaimed sustainability a state goal. HIDOT must move beyond its "more highways" strategy. This requires support from the Legislature, the governor and the U.S. Department of Transportation. It requires the availability of state and federal funds for transit, bicycle and pedestrian facilities. A good first step was the Legislature’s recent approval of $600,000 for bus shelters on Kauai.

Aligning HIDOT’s long-range land transportation plan with state and county goals will enable us to move toward a resilient land transportation system — and a sustainable future.