Heather Welles pairs litigation and appellate success at the highest levels with substantive expertise in water, a field of growing importance to even the largest companies. A diverse set of clients, including innovative farmers, major movie and television studios, large water districts, champion athletes, skin-care pioneers, private equity funds, and environmental conservation and recreational organizations rely on Heather to write case-winning briefs, develop persuasive legal theories, and creatively resolve disputes.
Heather’s briefs have repeatedly carried the day in federal and state trial and appellate courts and arbitrations, including merits, certiorari, and amicus briefing at the US Supreme Court. She has briefed subjects including federal and state constitutional law, federal courts and jurisdiction, statutory interpretation, water law, land use, public trust, contracts, administrative law, trademark law, and insurance law. She also has significant experience representing entertainment industry clients in contract, intellectual property, and audit disputes, including repeatedly succeeding in compelling arbitration in these cases, and in California state court appeals. A founding member of O’Melveny’s formal water practice, Heather regularly speaks on water issues, including guest lecturing at Harvard, NYU, and UCLA law schools. Heather maintains an active pro bono practice focused on civil rights and impact litigation.
In 2023, Law360 recognized Heather as a Rising Star, one of six top attorneys under 40 nationwide in environmental law. In 2022, the Daily Journal recognized Heather as one of the forty top lawyers under the age of 40 in California, highlighting her water work and appellate practice. Heather’s work has also been recognized by the Daily Journal’s California Lawyer Attorneys of the Year Award and Benchmark Litigation.
Prior to joining O’Melveny, Heather served as a law clerk for the Honorable David S. Tatel on the DC Circuit Court of Appeals and the Honorable William A. Fletcher on the Ninth Circuit Court of Appeals.
Heather graduated from the University of California, Berkeley School of Law, where she was awarded the Thelen Marrin Prize for Academic Excellence for graduating first in her class and served as the Editor in Chief of the Ecology Law Quarterly. She previously served as a legislative director in the Texas House of Representatives, where she worked on groundwater regulation, water quality, energy, and land use.
Representative Water and Natural Resources Matters
- Agua Caliente Band of Cahuilla Indians v. Coachella Valley Water District. Representing Coachella Valley Water District in federal court on multiple matters of first impression involving reserved water rights, including successfully obtaining dismissal of several claims on standing grounds at summary judgment.
- Las Posas Water Rights Coalition v. Fox Canyon Groundwater Management Agency & OPV Coalition v. Fox Canyon Groundwater Management Agency. Representing coalitions of large landowners in the first comprehensive groundwater adjudications under California’s groundwater management and adjudication statutes in complex trial and appellate proceedings. The Daily Journal’s 2024 California Lawyer of the Year Award recognized the Las Posas team’s successful settlement of most claims and wins in each of three trial phases.
- California Resources Corp. v. County of Monterey. Primary author of appellate briefing successfully defending a challenge to a local initiative impacting property rights and water use. Also obtained rare regulatory takings victory at bench trial as the primary brief drafter for the trial team and presented argument at trial and in collateral administrative proceedings.
- Advising on water rights and legal issues affecting water supply in multiple contexts, including disputes, major transactions, project development, governance, and regulatory compliance. Representative projects include multi-million-dollar transactions related to land and water rights acquisition and infrastructure development.
Representative Appellate Matters
- Erlinger v. United States. Obtained favorable ruling from the US Supreme Court requiring jury determination of facts necessary to impose mandatory minimum sentences under the Armed Career Criminal Act, reversing the unanimous position of the Courts of Appeals. The Court granted O’Melveny’s petition raising the issue over several competing petitions.
- City of Austin v. Reagan National Advertising of Texas Inc. Successfully represented the City of Austin at the US Supreme Court in a First Amendment dispute over billboard regulations, including obtaining certiorari and a favorable decision on the merits reversing the Fifth Circuit.
- Chama Troustalkers, LLC v. Adobe Whitewater Club of New Mexico. As counsel of record, successfully opposed certiorari in a case that protected public recreational use of non-navigable waters throughout New Mexico.
- Padilla Ortiz v. Garland. Briefed and secured a rare victory on the papers at the Ninth Circuit in an immigration case, obtaining relief for a young woman seeking asylum.
Representative Litigation and Counseling Matters
- Representing Warner Bros. in numerous contract and intellectual property disputes in trial, arbitration, and bankruptcy proceedings involving properties like the Matrix and Lord of the Rings franchises, along with a host of other film and television properties. Heather’s work for the studio also spans multiple contract disputes over digital cinema financing and counseling on COVID-19-related issues both in the U.S. and internationally.
- Representing The Walt Disney Company in dispute over a blockbuster film franchise and in litigation with a major film financer.
- Representing a health insurer in Administrative Procedure Act litigation against the US Department of Health and Human Services challenging a Medicare audit regulation that the agency spent a decade developing, including successfully defeating the government’s motion to dismiss and transfer venue.
- Served as the primary brief writer for a successful trial team defending a renowned dermatologist and his company in a contract and trademark dispute involving claims exceeding US$80 million.
- Served as the primary brief writer in a contract dispute defending a renowned boxer and his promoter.
- Counseled a prominent green-buildings company on First Amendment issues.
- Represented Planned Parenthood Arizona and individual clinicians in litigation challenging statutes that reduce access to reproductive health care.
Admissions
Bar Admissions
- California
Court Admissions
- US Supreme Court
- US Court of Appeals, Ninth Circuit
- US District Court, Central District of California
Education
- University of California at Berkeley, J.D.: Thelen Marrin Prize for Academic Excellence (best academic record in graduating class); Order of the Coif; Editor in Chief, Ecology Law Quarterly; Landis Prize (most accomplished research paper in water or local government law); American Jurisprudence Awards for best exam in Constitutional Law, Contracts, Water Law, and Land Use Law
- University of California at San Diego, B.A., Political Science
Honors & Awards
- Multiple trial wins in the Las Posas adjudication recognized by the Daily Journal‘s California Lawyer Attorneys of the Year (CLAY) Award (2024)
- Supreme Court victory in Erlinger v. United States recognized by the National Law Journal’s Appellate Hot List (2024)
- Named a “Rising Star” in Environmental Law by Law360 (2023)
- Named to the Daily Journal's "Top 40 Under 40" (2022)
- Member of the team recognized as Environment/Natural Resources Litigation Firm of the Year by Benchmark Litigation California (2019)
Professional Activities
Clerkships
- The Honorable David S. Tatel, US Court of Appeals, District of Columbia Circuit
- The Honorable William A. Fletcher, US Court of Appeals, Ninth Circuit
Publications
- “Toward a Management Doctrine for Texas Groundwater,” Ecology Law Quarterly, Vol. 40 (2013)
- “What’s a Smelt Worth?: The Endangered Species Act and the Commerce Clause in the Bay-Delta,” Ecology Law Quarterly, Vol. 39 (2012)
- “Will the Wilderness Act Be Diluted in Drakes Estero?” Ecology Law Quarterly Currents (Aug. 26, 2012) (co-authored with Nell Green Nylen, Elisabeth Long, Mary Loum, Dan Carlin, Brynn Cook, and Sage Adams)
Speaker
- “SGMA Throughout California,” Kern County Water Summit (March 2025)
- “From Conflict to Collaboration: Groundwater Adjudication and Sustainability in the Post-SGMA World,” H2O Women Conference (October 2024)
- “No Stone Unturned: Securing Water for a New Era,” USC Gould School of Law’s 2024 Real Estate Law & Business Forum (February 2024)
- “Tribal Water Rights & Groundwater Recharge,” Urban Water Institute, 2019 Spring Conference (February 2019)
- “Tribal Water Rights & Groundwater Recharge,” UCSB Bren School of Environmental Science & Management, Sustainable Water Markets Symposium (November 2018)
- “Global Water Hotspots & U.S. Military Priorities,” Pacific Council on International Policy, 2017 Water Conference (December 2017)
Lecturer
- “The Business of Water,” Stanford Law School (Fall 2024) (co-instructor)