By The Herald Editorial Board

After having done the heavy lifting to put together a plan to extend Sound Transit’s Link light rail system in Snohomish, King and Pierce counties — which voters approved this month — the members of Sound Transit’s board of directors are likely to face a legislative challenge that would oust them in favor of a board of directly elected representatives.

That’s gratitude for ya.

But it’s a proposal worth discussion as the Puget Sound’s most populous counties work to build not only the ST3 light rail extension, but also continue to study, plan, fund and implement the entire region’s transportation needs during the next 25 to 30 years.

Sen. Steve O’Ban, R-University Place, and Rep. Mark Harmsworth, R-Mill Creek, said they will reintroduce legislation in the 2017 session that would replace the current board with a 19-member board of locally elected representatives, each from a separate district in Sound Transit’s taxing district, which includes portions of Snohomish, King and Pierce counties.

“Making this board accountable to the people directly is consistent with a long cherished tradition of democracy” to provide representation regarding taxation, O’Ban told The Herald’s Jerry Cornfield last week.

The current Sound Transit board’s members are elected officials, though not elected specifically to that role. The board includes each of the three county executives, who then appoint the rest of the 17-member board from local cities’ elected officials. Snohomish County’s representatives are County Executive Dave Somers, Everett City Councilmember Paul Roberts and Edmonds Mayor Dave Earling.

That model was effective as Sound Transit planned and started construction of the light rail system, guided by a board of directors who were each already informed about their community’s transportation and other needs.

O’Ban, Harmsworth and others now make the case that following passage of the funding package for ST3, the voters who approved increases to their vehicle tabs, sales tax and property tax will need representation that they elect directly. The stakes, admittedly, are high; voters approved $54 billion in spending over the next 25 years.

Critics of the legislation defend the current system as best able to provide regional planning and leadership.

“Balkanizing the system is not an answer to building a regional system,” Roberts told The Herald.

We do wonder if the needs of Snohomish County, which would still only have three members compared to King County’s 12, would have a strong enough voice under the proposed system. Had O’Ban’s and Harmsworth’s legislation passed earlier, a block of King County districts might have favored their own projects over the proposal to extend light rail to the manufacturing jobs center at Paine Field.

We’re not convinced that a representative elected to a particular district would be as committed to the region’s needs as he or she would be to the voters of that singular district.

And the legislation does nothing to streamline a complex and intertwined system of transportation agencies in the region that, while usually cooperative, complicates planning to avoid duplicating services and sometimes finds agencies competing for the same resources. A better solution would be a truly regional transportation system, led by a combination of directly elected representatives and other officials with background expertise in relevant areas.

Ten years ago, at the Legislature’s request, a nine-member panel — two of whose members were Snohomish County’s Reid Shockey and Gigi Burke — studied the Puget Sound’s regional transportation system. The panel, the Regional Transportation Committee, produced a report that recommended “reknitting” an infrastructure that included a patchwork quilt of 128 separate agencies that managed aspects of transportation in Snohomish, King, Pierce and Kitsap counties into a regional system led by a 15-member board.

Leaders and lawmakers should take the report down from the shelf, dust it off and read it.

The Puget Sound Regional Transportation Commission board was to be led by nine nonpartisan commissioners, elected from proportional districts. The six other board members were to be appointed by the governor based on expertise in specific subject areas, such as planning, construction, finance and management.

Under the proposal, the four-county region would keep as a block grant the tax revenue it generates within its borders from the gas tax, vehicle tabs and other sources and use it for regional transportation needs. It would also have the ability to levy its own taxes and set regional tolls.

Taking such a large chunk of resources and authority from the state and combining so many agencies will raise concerns for many. But we face bigger problems. Between now and 2040, the Puget Sound region is expected to add 1 million new residents. The 4.9 million residents of the region in 2040 will require not only representation but a governing body on transportation issues that is organized, focused and responsive.

Picking new members for the Sound Transit board addresses only one patch in the quilt.

Correction: An earlier version of this editorial incorrectly identified the party affiliation of Rep. Mark Harmsworth of Mill Creek. He is a Republican.