Nossaman LLP

Katrina Diaz


T 949.477.7661
F 949.833.7878
18101 Von Karman Avenue, Suite 1800
Irvine, CA 92612

Katrina Diaz is an eminent domain, land use, and real estate litigation attorney, primarily focused on eminent domain, inverse condemnation, regulatory takings, valuation matters, and environmental litigation.

Ms. Diaz has worked on some of the largest public works projects for some of the largest public agencies in California, such as San Diego Association of Governments, Los Angeles County Metropolitan Transportation Authority, San Bernardino County Associated Governments, Exposition Metro Line Construction Authority and Orange County Transportation Corridor Agencies., Ms. Diaz plays an active role in project planning and implementation, defending environmental documents, assisting with the precondemnation and condemnation acquisition process, drafting and negotiating possession and use and purchase and sale agreements, preparing pleadings and motions, attending hearings, propounding and responding to discovery, and assisting with trial preparation. 

Ms. Diaz also represents a broad-range of property and business owners in California. 

Ms. Diaz is committed to civil justice and provides pro bono legal assistance and other support to the Orange County Public Law Center.

A former Nossaman summer associate, Ms Diaz served as a judicial extern for Justice Kathleen E. O'Leary at the California 4th District Court of Appeal, Division Three, a law clerk for the City Attorney of Orange, and volunteered at the Public Law Center.

Ms. Diaz regularly comments on news, events, and policies regarding Eminent Domain on the Firm's Eminent Domain & Valuation blog. 

Representative Work

San Bernardino County Transportation Commission.  Currently representing SBCTC with the acquisition of approximately 65 properties for the Downtown Passenger Rail Project, a proposed Metrolink commuter rail line between San Bernardino and Redlands.

Orange County Transportation Corridor Agencies.  Currently part of the team representing the TCAs in defending the SR 241 Extension Project. 

Exposition Metro Line Construction Authority.  Currently part of the team assisting Expo with acquiring commercially developed properties in Santa Monica necessary for future terminal stations for Phase II of the Project, along with securing easements for street widening and utility relocations.

San Diego Association of Governments.  Currently part of the team representing SANDAG with project planning and right of way acquisitions for the Mid-Coast Corridor Transit Project, the South Bay BRT Project, and the Inland Rail Trails Project.

Los Angeles County Metropolitan Transportation Authority.  Currently assisting MTA with acquiring property necessary for the LAX/Crenshaw Transit Corridor Project and the Westside Subway Extension (Purple Line).

San Bernardino Association of Governments.  Currently part of the team representing SANBAG with acquiring portions of 150+ properties for the sbX E-Street Corridor Bus Rapid Transit Project, a 15.7-mile bus rapid transit line in the Inland Empire.

Awards & Honors

Wiley W. Manuel Certificate for Pro Bono Legal Services, California State Bar Association, April 2014
Bio Photo
Bio Photo



J.D., Chapman University School of Law, 2012, cum laude; Articles Editor, Chapman Law Review; Moot Court Executive Board Member

B.A., University of California, Irvine, 2006



United States District Court, Central District of California

Professional Affiliations

Women Transportation Seminar, Scholarship Committee Chair, Orange County Chapter

International Right of Way Association, Legislative Chair, Chapter 67

The Orange County Diversity Task Force, Committee Member

Orange County Bar Association, Pro-Bono Committee Member

Awards & Honors

Wiley W. Manuel Certificate for Pro Bono Legal Services, California State Bar Association, April 2014
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