Combining two proposed rail lines is expected to free up some $400 million in Metro’s next wave of bus and rail expansion, allowing the transit agency to add two long-sought park and ride connections to the list voters are likely to consider in November.

The estimated price of extending the Green Line and Purple Line light rail to Hobby Airport, by combining the two lines and focusing on a route along Broadway, dropped from $1.4 billion to about $1 billion, Metropolitan Transit Authority officials said Friday.

Metro’s board is nearing a final vote on asking voters for permission to borrow $3.5 billion for a suite of transit projects, the first portion of the agency’s MetroNext long-range plan. Officials must approve a plan by mid-August and call for an election, in order to have it appear on the November ballot.

Likely projects for the ballot proposal include extensions of the Red, Purple and Green light rail lines, 75 miles of proposed bus rapid transit and various park and ride additions or expansions.

Because of the estimated $400 million savings, those projects could be joined by a $336 million extension of the light rail line from Hobby to the Monroe Park and Ride lot near Interstate 45, and relocating the Kingwood Park and Ride closer to Interstate 69, at an estimated cost of up to $60 million.

Both projects were popular with respondents during Metro’s year-long public meeting process about a long-range transit plan, and also have support from local elected officials.

The Kingwood site was an obvious choice, Metro CEO Tom Lambert said, because it was affected by flooding when Tropical Storm Harvey deluged Houston. The existing site along Kingwood Drive also is time-consuming for buses to navigate, compared to a location closer to the freeway.

The Monroe rail extension, meanwhile, would provide a place for suburban residents to park and then ride the rail to various job centers.

More parking around Hobby also remains a priority as transit officials provide commuter-centric options to access rail, Metro board member Jim Robinson said.

“We have some conservative votes we won't get if we don't do it,” Robinson said.

BRT is M.I.A.: Metro must make case for bus rapid transit without something to show voters

A final decision on what projects are added will come later this month, Metro Chairwoman Carrin Patman said, noting she was not completely sold on the rail extension to Monroe. Further study will be needed to finalize details so they can presented to voters.

Though dominated by the discussion of rail to Hobby, the proposed transit plan would add services in almost every corner of Metro’s nearly 1,300-square-mile coverage area. Key projects include bus rapid transit along Interstate 10 inside Loop 610 — speeding trips from the Northwest Transit Center to downtown Houston — and lengthy bus rapid transit systems that would connect downtown to Bush Intercontinental Airport and from the Tidwell area, through downtown and then west to locations at or near Greewnay Plaza, Uptown and eventually Westchase.

Patman said projects will be built as warranted and as Metro secures various approvals, which will be crucial to building some of the projects using federal transit dollars along with local money. Exact project costs, she added, will determine what gets built and when.

In 2003, the last time Metro sought voter approval to expand rail lines and add bus service, only a handful of projects listed were ever built. The $650 million in borrowing authority voters approved added roughly 15 miles of rail and left many projects — notably a light rail line from dowtown to the Uptown area — shelved.

If voters approve the plan in November, it will not lead to any change in taxes or any added costs for residents. Metro collects a 1 percent sales tax in Harris County, Houston and 14 other member cities. Slightly more than three-quarters of that sales tax remains with Metro for operations and transit expansion. Voters must approve anytime Metro borrows money, based on paying it back with future tax revenues.

dug.begley@chron.com