The stretch of H-1 freeway near the Pearl City off­ramps, in both directions, ranks as the riskiest on Oahu by one measure, according to a new five-year review of traffic accidents involving injuries.

The report, released Thursday by the state Department of Health, says emergency medical services responded to 32 accidents that caused injury on the H-1 eastbound near the Pearl City off­ramp, and to 30 injury accidents in the westbound lanes in that spot during the five-year period from 2007 through 2011.

Those were the top two injury-accident sites involving cars and trucks for that period.

The other categories were motorcycles/mo-peds, bicycles and pedestrians.

"The areas near the off­ramps at Pearl City appear to be problematic," said Dan Gala­nis, epidemiologist with the DOH Injury Prevention Program. "They serve large volumes of traffic, so the numbers may not even reflect the higher risk given the tens of thousands of cars that go through there."

The DOH Injury Prevention and Control Section released a report containing 160 detailed maps showing locations and numbers of injury accidents.

"We want the map book to be a resource or reference for groups interested in traffic safety, be they government agencies, community groups, neighborhood boards or other planning organizations," Gala­nis said. "It’s meant to be a resource, a tool in focusing the traffic injury prevention efforts of those groups."

Pearl City also had the top surface-street crash site: Kamehameha Highway and Acacia Road, near Home Depot, with 29 injury accidents.

Cruz Vina Jr., Pearl City Neighborhood Board vice chairman and head of the board’s Traffic and Transportation Committee, acknowledged that the aforementioned areas on the H-1 freeway are of concern because they are high-volume traffic spots with a lot of lane-changing — especially the westbound lanes.

"As it is right now, the traffic in the eastbound direction, we can handle that," he said. "The traffic going westbound, especially from the Pearl City cutoff to the Wai­pahu cutoff, we feel is more problematic."

The state Department of Transportation has been working on a major H-1 improvement project in that area since mid-2012 that will eventually involve re-striping westbound lanes from the Aiea pedestrian overpass to the Pearl City off­ramp to create an extra exit lane; expanding the viaduct between the Pearl City onramp and Wai­pahu off­ramp to add an auxiliary westbound lane; and creating a Zipper Lane that could stretch from the Halawa interchange to the H-1/H-2 merge for westbound evening traffic, DOT spokes­woman Caroline Sluyter said.

The changes "will help with merging and weaving in the area," she said.

The project is expected to be completed in late summer 2014. Crews are repairing the freeway’s concrete deck in preparation for the re-striping and expansion.

Sluyter said the DOT does not have plans at this time to re-stripe or add another lane on the eastbound side.

Here are the top spots, according to the Department of Health, for the other categories of injury accidents:

» Motorcycles/mo-peds: Two intersections on Kapiolani Boulevard, at Atkinson Drive and at Keeaumoku Street, were tied for the most injury accidents with 10 apiece.

» Bicycles: Three tied for first with four incidents each: Ala Wai Boulevard and Kalakaua Avenue; Wai­alae Avenue and St. Louis Drive; and King and Hau­oli streets.

» Pedestrians: Ala Moana Center was tops with 14, with the nearby Kapiolani-Keeaumoku intersection second at eight.

"We are taking a look at the report, but have not yet had an opportunity to review it in full detail," Francis Cofran, general manager of Ala Moana Center, said in a statement to the Star-Advertiser. "Anything that relates to safety around Ala Moana Center is always a concern to us. The safety and security of our shoppers are always our top priority."

Bruce Bottorff, associate state director of AARP Hawaii, said, "Generally speaking, if you look at Ala Moana and draw a ring around it — Atkinson where it meets with Kapiolani and Ala Moana boulevards and where Pensacola meets Kapiolani on the other end — that whole area is one that is prone to accidents simply because there’s so much traffic moving in all directions, and people are trying to move in and out on foot and bike."

To address traffic safety issues, especially those involving pedestrians, Bottorff said three major areas of focus are education, enforcement and infrastructure.

"One thing is education, and I don’t just mean drivers, but pedestrians have to be educated as well," he said. "Enforcement is another. HPD has gone out into the community and given mock citations to people where they have been observed disregarding the law. We continue to believe laws need to be enforced, such that motorists and pedestrians are aware of the law.

"Third is infrastructure. That increasingly is an area of our attention, and the ‘complete streets’ bills and ordinances address this. Because we are becoming so urbanized and there is an increasingly dangerous mix of cars and people on our roads, we need to be mindful of the need for updates to our infrastructure.

"The point is there has to be continued vigilance in all three areas."

Michael Formby, interim director of the city Department of Transportation Services, said many factors may contribute to an accident and that at this time "there is nothing to indicate we need to make changes" in the Ala Moana area.

Formby said traffic engineers require detailed information about individual accidents and why they occur to make any meaningful recommendations for change, but added that the map book could aid the department in finding areas that may warrant considerations for change.

The report uses Oahu neighborhood districts to place the injury accidents into 35 geographic areas. The Kalihi-Palama had the most injury accidents in the five-year period, with 1,070.

Other highlights:

» Makakilo-Kapolei had the most car/truck injury accidents, with 759.

» Waikiki had the most motorcycle/mo-ped incidents, with 168.

» Ala Moana-Kakaako had the most bicycle incidents, with 47.

» Kalihi-Palama had the most pedestrian incidents, with 171.

» Alcohol is a factor in two-thirds of Oahu traffic fatalities.

» Vehicle occupants not wearing a seat belt are three times more likely to be killed in a serious collision than people wearing seat belts.