An outside investigation of a $11.5 million office building for sewer workers that tripled in cost recommends Portland city bureaus provide elected officials with detailed reports when the scope of a construction project changes.

City Commissioner Nick Fish asked law firm Barran Liebman to review the project, which eventually cost longtime Bureau of Environmental Services chief Dean Marriott his job.

On Wednesday, The Oregonian obtained records that lifted the curtain on the fractious relationship between Fish and Marriott in the aftermath of the project.

The Barran Liebman report, also released Feb. 18, says bureau officials violated no laws or city rules as the office project grew. But it says Marriott and other BES officials allowed the elaborate design of the building to change the project's scale and budget.

The report suggests the creation of new city memos to disclose enlarged scope.

"The Bureau should provide to the Commissioner in charge of the Bureau a detailed report of all requested additions to the scope of a project prior to undertaking the implementation of the additions," the report says. "It is recommended that those requested or necessary additions to the scope be put into a separate memorandum to the Commissioner which clearly is designated as a 'Scope Enlargement' request."

The Barran Liebman investigation follows a damning city audit into the Columbia Wastewater Treatment Plant services building, which tripled in costs to $11.5 million.

Fish asked for the audit after WW and KOIN-TV reported how the city turned what was supposed to be a utilitarian office building, originally estimated at $3.2 million, into a "poster-child facility" for wastewater engineers in North Portland.

The audit showed bureau managers approved a design so ornate and inadequate that it required 85 change orders during construction, mostly to fix design problems like the ecoroof covered in wetland grasses.

Fish responded to WW's report by mandating that any BES and Water Bureau spending over $500,000 be discussed by City Council. He placed Marriott on leave, and the 20-year bureau chief resigned in January.