L.E. Phillips Memorial Public Library project

This rendering from MSR Design shows the renovated exterior of L.E. Phillips Memorial Public Library and a third story added to the building.

EAU CLAIRE — The philanthropic arm of Eau Claire-based Royal Credit Union is pledging a $500,000 contribution to the L.E. Phillips Memorial Public Library expansion project.

The library's Story Builder fundraising campaign announced the pledge from the RCU Foundation on Tuesday, stating it is among the largest contributions to the project to date.

“We’re proud to have such generous support from the RCU Foundation," Kimberly Hennings, the library's deputy director, said in a news release. "RCU is truly a pillar of this community and especially for Eau Claire’s downtown area, the place the library calls home."

In recognition of the contribution, the foundation gets naming rights for the library's "dabble box" — a hands-on learning lab.

The latest gift brings the fundraising campaign up to about $3.5 million of its $7 million goal to fund the building's expansion.

Other major contributors announced to date are the Pablo Foundation ($750,000), Mayo Clinic Health System ($250,000), Charter Bank and Lasker Jewelers ($100,000 each). Several individuals also have pledged contributions of $100,000 or more.

Aside from money raised to enhance the library, the city of Eau Claire is already contributing $11.5 million to revamp the building's aging mechanical systems.