Hayley Siltanen is a land and natural resources attorney, with a practice focused on land use, permitting, and water rights law.

Hayley helps commercial, industrial, and residential clients entitle their projects and defend their land use entitlements against challenges before the Oregon Land Use Board of Appeals and Oregon Court of Appeals.

Hayley also helps water suppliers and water users acquire, change, and protect their water rights. She has counseled private individuals, clients in natural resources industries, including agribusinesses and energy companies, and municipal and special district water providers on matters related to water supply and compliance with water right laws and regulations. She also regularly advises property owners and prospective buyers regarding water rights associated with agricultural, commercial, and industrial properties.

Following law school, she was as a summer clerk at the California Attorney General’s Office, focusing on environment and land use law.


University of California, Berkeley, School of Law, J.D., 2016, Environmental Law Certificate; Editorial Board, Ecology Law Quarterly

Oregon State University, B.S., Industrial Engineering, 2011, summa cum laude






Land Use & Real Estate

  • Assisted clients to obtain state and local land use entitlements and environmental permits for commercial development and energy projects in Oregon and Washington.
  • Managed agricultural and residential real estate transactions in Colorado by performing title examinations, resolving title problems, preparing conveyancing documents, reviewing and managing closing documents, and effectively communicating with all parties to the transaction to coordinate closing.
  • Conducted due diligence examinations for commercial, industrial, and residential properties to analyze zoning, entitlement, and other land use matters.
  • Advised clients on land use and real estate matters, including eminent domain, boundary disputes, and easements.

Water Rights

  • Represented clients before the Oregon Water Resources Department and in Colorado water courts concerning new water rights, water right transfers, augmentation plans and water rights abandonment protests, and in other disputes related to ownership, use, and development of water resources.
  • Regularly counseled agricultural, commercial, industrial, municipal, and private individual water users on matters related to water supply and compliance with water rights laws and regulations.
  • Served as lead water counsel for municipal water supplier.
  • Regularly advised property owners and prospective property purchasers regarding water rights associated with agricultural, commercial, and industrial properties.
  • Drafted water rights purchase and sale agreements, ditch sharing agreements, well easement agreements, and other water-related agreements.


Insights & Presentations

  • Co-author, “Chapter 15: Water Rights,” Colorado Department of Regulatory Affairs, Real Estate Manual, 2022 Edition
  • Co-author, “SPROWG: A Collaborative Water Supply Concept,” American Bar Association Natural Resources & Environment, Fall 2020
  • Co-author, “Federal Government Allowed to Join Texas in Claims Against New Mexico for Breach of Water Compact,” Oregon Real Estate and Land Use Digest, Section on Real Estate and Land Use, Oregon State Bar, June 2018
  • “Accounting for Partial Settlements in CERCLA Private Party Cost Allocation: No Rule is the Best Rule,” Ecology Law Quarterly, February 2017


  • Ellis J. Harmon Prize for most accomplished paper on environmental law for article in Ecology Law Quarterly, 2016
  • Prosser Prize in Environmental Law Writing, 2015
  • Jurisprudence Award in Written and Oral Advocacy, UC Berkeley Law, 2014



  • Oregon State Bar Environmental & Natural Resources Section, Member
  • Oregon State Bar Real Estate & Land Use Section, Member
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