Heather Welles


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Heather Welles focuses her practice on complex litigation and appeals, with a particular focus on water and public law issues. She has drafted briefs in federal and state trial and appellate courts, including the US Supreme Court, on a range of subjects, including federal constitutional law, federal courts and jurisdictional issues, statutory interpretation, water law, land use, contracts, and trademark law. Heather is a core member of the firm’s water practice, representing clients in areas including public agencies, agriculture, energy, private equity, and environmental conservation, and she advises on water projects in various contexts, including both litigation and transactions. Heather also maintains an active pro bono practice focused on civil rights and impact litigation.


Honors & Awards

  • Member of the team recognized as Environment/Natural Resources Litigation Firm of the Year by Benchmark Litigation California (2019)


Bar Admissions

  • California

Court Admissions

  • US Court of Appeals, Ninth Circuit
  • US District Court, Central District of California


  • 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 

Professional Activities


  • Honorable David S. Tatel, US Court of Appeals, District of Columbia Circuit
  • Honorable William A. Fletcher, US Court of Appeals, Ninth Circuit


  • “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)

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 two comprehensive groundwater adjudications under California’s new statutory adjudication scheme.
  • 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.
  • Advised a major energy company and a major utility company on federal constitutional and statutory issues related to international and interstate pipelines, including appellate briefing and strategy, consulting with federal officials, and regulatory advice. 
  • Represented a nonprofit organization in connection with high-profile negotiations over water quality in the Sacramento/San Joaquin River Delta system.

Representative Appellate Matters

  • City of Austin v. Reagan National Advertising of Texas Inc. Representing the City of Austin at the US Supreme Court in a First Amendment dispute over billboard regulations.
  • 11 Lagunita, LLC v. California Coastal Commission. Primary author of appellate briefing in a California Court of Appeal case involving administrative res judicata and Coastal Commission enforcement authority.
  • California Resources Corp. v. County of Monterey. Primary author of appellate briefing defending a successful 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.
  • Bostock v. Clayton County. Co-authored amicus brief on behalf of anti-violence organizations before the US Supreme Court defending a Sixth Circuit decision holding that transgender Americans are protected by Title VII’s prohibition on discrimination on the basis of sex.
  • Padilla Ortiz v. Garland & Cardenas Leal v. Garland.  Appellate briefing in Ninth Circuit cases appealing decisions by the Board of Immigration Appeals.

Representative Litigation and Counseling Matters

  • Representing Warner Bros. in several important matters, including an international contract dispute and counseling on COVID-19-related issues.
  • 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 $80 million.
  • Served as the primary brief writer in a contract dispute defending a renowned boxer and his promoter.
  • Advised a government agency and nonprofit organization on constitutional, statutory, and regulatory issues related to immigration.
  • Represented Planned Parenthood Arizona and individual clinicians in litigation challenging statutes that reduce access to reproductive health care.