Would a new carpool lane bring more cars to Highway 50 downtown? New lawsuit says yes.

Caltrans wants to add carpool lanes to the W/ X freeway. Environmentalists are suing to stop.
Caltrans wants to add carpool lanes to the W/ X freeway. Environmentalists are suing to stop. RBenton@sacbee.com

An environmental group has sued Caltrans over the state’s plans to build carpool lanes on Highway 50 in downtown Sacramento, saying the state has failed to analyze the health impacts on local residents from potential increased vehicle emissions.

The lawsuit, filed by the Environmental Council of Sacramento earlier this month in Sacramento Superior Court, is focused on the state’s plan to extend its existing Highway 50 carpool system west from Watt Avenue to Interstate 5. The freeway already has a set of carpool lanes running east from Watt Avenue into El Dorado County.

Caltrans chose not to conduct a full environmental review of the new project, indicating it believes the project is not expected to create significant environmental issues.

Carpool lanes, also known as high-occupancy vehicle or HOV lanes, typically are reserved for vehicles carrying more than one or two people during morning and afternoon commute periods, but are open to all drivers the rest of the time. That has prompted environmentalists to argue the lanes are not nearly as environmentally friendly as they are billed.

ECOS, in a press statement Monday, contended the project in fact is a freeway expansion that would “lead to a significant increase in vehicles on the freeway.”

The environmental group said it would support a carpool lane extension through downtown if the state were to turn two existing lanes into carpool lanes rather than expand the freeway, which environmentalists say will encourage more sprawl-style growth, cause more people to drive longer distances, and increase “greenhouse gas emissions that contribute to climate change.”

Ralph Propper of ECOS, a former air pollution researcher with the California Air Resources Board, said Highway 50 runs through residential areas, and points out that some studies have linked proximity to freeways with a variety of health problems.

Caltrans tentatively plans to begin construction of the $187 million project in 2019, if it can obtain the funds. The state bills the project as a way to use the freeway more efficiently, reduce travel times by adding traffic flow capacity through that corridor, and to increase the incentive for commuters to ride-share and carpool.

Caltrans is working on a decades-long effort to add carpool lanes on all Sacramento area freeways. Caltrans officials did not immediately respond to a Bee request for comment.

A few years ago, when Caltrans did repairs on the elevated section of Highway 50 through downtown, the work sent dust wafting into neighborhoods a block away.

ECOS previously sued Caltrans over the state’s carpool lane expansion plans between Watt Avenue and Sunrise Boulevard, leading to a 2009 out-of-court settlement, allowing Caltrans to build the lanes. In exchange, Caltrans agreed to provide $7 million for improvements to the Sacramento Regional Transit light-rail line that parallels the freeway, and funds to build a pedestrian and bike crossing over the highway near Mather Field Road and a light-rail station.

Tony Bizjak: 916-321-1059, @TonyBizjak

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