Beveridge & Diamond
Timothy M. Sullivan photo

Timothy M. Sullivan


201 North Charles Street
Suite 2210
Baltimore, MD 21201-4150

  • Fairfield University (B.A., History, 1993)
  • Lewis & Clark College, Northwestern School of Law (J.D., magna cum laude, 2000; Environmental Law Review 1998-2000, Managing Editor 1999-2000, Certificate in Environmental and Natural Resources Law, Cornelius Honor Society)
Bar Admissions & Memberships
Bar Admissions & Memberships
  • Oregon
  • Washington
  • Maryland
  • District of Columbia
  • U.S. District Courts: District of Oregon, District of Maryland, District of Colorado, Eastern District of Washington, Western District of Washington
  • U.S. Court of Appeals, Ninth Circuit
  • American Bar Association Section of Environment, Energy, and Resources Endangered Species Committee, Vice-Chair (2003-2010)
  • Maryland State Bar Association Environmental Law Section, Member (2006-present), Chair (2010-11), Section Council (2006-2012)
  • Oregon State Bar Administrative Law Section, Executive Committee (2003-2005)
  • Oregon State Bar Environmental and Natural Resources Law Section (2001-present)

Tim Sullivan's practice focuses primarily on environmental and natural resources litigation before federal and state courts and adjudicatory bodies. He represents and advises public and private clients in regulatory, litigation, and other matters involving many federal and state environmental and natural resources laws, with a particular emphasis on CERCLA, the Endangered Species Act, and the Clean Water Act. Mr. Sullivan is the Managing Principal of Beveridge & Diamond's Baltimore office. 

Examples of Mr. Sullivan’s experience include:

  • Representation through trial of a Class I railroad in a Clean Water Act citizen suit in Washington State;
  • Representation of a major water and sewer utility in a Clean Water Act citizen suit in Maryland;
  • Negotiation of a Clean Water Act Sanitary Sewer Overflow (SSO) Consent Decree extension for a major water and sewer utility in Maryland;
  • Counsel to a major water and sewer utility with respect to Clean Water Act compliance and enforcement issues;
  • Representation of a petroleum exploration and production company in litigation arising from an operator’s use of the company’s platform on the Outer Continental Shelf of the Gulf of Mexico;
  • Representation of a petroleum refining company in CERCLA litigation in the Eastern District of New York
  • Representation of petroleum refining company in litigation with the United States under the Pennsylvania Tank Act, Clean Streams Law, and Uniform Contribution Among Tortfeasors Act;
  • Representation of an equipment supplier in construction disputes involving wastewater treatment plants;
  • Representation of a group of ports and other navigation interests on the Columbia River in Endangered Species Act citizen suit litigation challenging federal operation of the Federal Columbia River Power System;
  • Representation of a Columbia River port in a complex land and water property development project challenged by a citizen’s group in an area containing wetlands and ESA-listed and state-protected species, including development of NEPA and Washington SEPA analyses;
  • Representation of timber company in administrative dispute with the Washington Dept. of Forestry involving logging in areas constituting potential habitat of ESA-protected marbled murrelet;
  • Representation of an Oregon county in federal permitting, enforcement, and litigation, related to construction of a 60-mile natural gas pipeline with almost 200 Clean Water Act jurisdictional water and wetlands crossings, many of which involved habitat for ESA-listed salmonids;
  • Representation of an industry group in Clean Water Act and Endangered Species Act citizen suit litigation challenging Oregon’s water quality standards;
  • Representation of mushroom producer in Oregon in enforcement action arising from wet weather discharges of stormwater.

In addition to his work for clients, Mr. Sullivan is also active in state and federal professional activities. He is an adjunct Professor of Law in the Environmental Law Program at the University of Maryland School of Law where he teaches a seminar in Federal Public Lands and Natural Resources Law. He has also served as the Chair of the Environmental Law Section of the Maryland State Bar Association and as a Vice-Chair of the Endangered Species Committee of the ABA’s Section on Environment, Energy, and Resources.

Mr. Sullivan came to Beveridge & Diamond in 2006 from Portland, Oregon, where he represented clients in matters involving environmental and natural resources law and litigation for five years with a regional Pacific Northwest law firm.


"CWA Citizen Suits: Notice, Standing & Interpleading Third Parties," webinar (March 2018)

"The Water Quantity-Water Quality Nexus: Two Sides of the Same Coin or Zero-Sum Game?" presented at National Association of Clean Water Agencies (NACWA) National Clean Water Law Seminar, Savannah, GA (November 2017)

“NEPA and Other Environmental Implications for Upstream Oil and Gas Operations,” presented at EUCI Oil and Gas Production on Federal Lands Conference, Denver, CO (March 2013)