Plans to use the fast lanes of U.S. 290 during some hours for carpools and buses is proceeding, with transit officials that sought the change picking up the tab.

The Metropolitan Transit Authority board on Thursday approved spending $1.6 million to stripe the freeway and install signs explaining the off-peak HOV, or high occupancy vehicle, lanes, which will outline the hours and warn solo drivers to avoid the lane.

When state and Harris County transportation officials in 2014 revised plans for widening U.S. 290 to create only one reversible high occupancy toll, or HOT, lane instead of the three originally proposed, Metro sought a way to accelerate trips back and forth to northwestern park and ride lots.

In the mornings, when traffic is heaviest eastbound toward Loop 610 and downtown Houston, the left lane westbound will be an HOV lane. During evening commutes when traffic is worse westbound, the eastbound left lane will be HOV-only.

“Even that is going to be an extremely important enhancement,” Metro Vice Chairman Jim Robinson said, noting Metro had hoped for more but opted to “settle” for the off-peak lanes.

On HoustonChronicle.com: Off-peak HOV lanes considered for U.S. 290

In peak times, as buses ferry people to and from work, one of the most time-consuming parts of providing service is return trips, sometimes called deadheading because the buses carry few if any passengers. Providing a way to avoid even the lighter - but still clogged - reverse direction with HOV lanes means buses can make more round trips, giving people more riding options.

The lanes will be used as HOV lanes from 6 a.m. to 9 a.m. westbound and 3:30 p.m. to 7 p.m. eastbound. Outside those times, the lanes are open to all users.

Metro spent more than two years discussing how to quicken trips along U.S. 290 with the Texas Department of Transportation, which is rebuilding the freeway. The off-peak HOV lanes required TxDOT to host public meetings, held earlier this month, to adjust its plans.

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Work along U.S. 290 is in its seventh year and on pace for all freeway lanes to open by the end of the year. When completed, U.S. 290 will be five lanes in each direction from Loop 610 to Texas 6, with four lanes to the Grand Parkway and three lanes to Waller County, at a construction cost of $1.8 billion.

Metro CEO Tom Lambert said transit police will patrol the lanes, and enforce violations by solo drivers, as they do with the existing HOT lanes along Houston-area freeways. Officials on Thursday said they could not estimate the annual costs of the added patrols, but did not think they would alter current budgets.

Unlike HOT lanes, however, the part-time HOV lanes will not be divided from the rest of traffic by concrete barriers.

“It is a challenge from an enforcement standpoint,” he said.

dug.begley@chron.com

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