1948 – Federal Water Pollution Control Act enacted. As amended in 1972, the law became commonly known as the Clean Water Act. The 1972 amendments established the basic structure for regulating pollutant discharges into the waters of the United States.
1999 – Consent decree resolves Heal the Bay and Santa Monica Baykeeper lawsuit to enforce the Clean Water Act. California Environmental Protection Agency and Los Angeles Regional Water Quality Control Board must set – and constituent cities, counties and others must achieve – Total Maximum Daily Loads (TMDLs) for pollutants such as metals, bacteria and solid debris flowing into Santa Monica Bay
January 2007 – Cheviot Hills resident Jonathan Weiss begins discussing with environmentalists his idea of daylighting storm drains passing under future Expo light-rail line.
February 2007 – UCLA Extension Landscape Architecture student Dean Howell provides “presentation sketches” for Expo Greenway concept.
May 21, 2007 – “I am writing in strong support of your proposal ....” (State Sen. Sheila Kuehl)
July 2008 – Dean Howell expands “Expo Green Corridor” idea into his student “thesis,” calling it the “Expo Greenway.”
July 3, 2009 – Reza Iranpour, Assistant Division Manager of the Los Angeles Department of Public Works’ Bureau of Sanitation Watershed Protection Division, takes an early-morning tour of the site that leads him to take on the project.
March 18, 2011 – Expo Board unanimously chooses the “no parking” option for Expo Light Rail’s Westwood station, freeing the land for a Greenway.
November 17, 2011 – The Greenway “will not only facilitate the cleanup of urban runoff and help the city deal with TMDLs, but will also be a vast improvement in the park poor section of the city.” (Los Angeles City Councilmember Paul Koretz)
April 2012 – Watershed Protection Division of the Bureau of Sanitation issues a Final Concept Report.
August 2012 – Mayor Villaraigosa puts Expo Greenway “on the map” as one of the new parks in his 50 Parks Initiative.
June 27, 2013 – Groundbreaking ceremony marks installation of culverts beneath the Expo light rail line to carry the creek from one side of the Expo Line tracks to the other.
July 8, 2013 – Steering Committee of stakeholders convenes.
October 3, 2013 – Steering Committee hosts City of LA Staffers, TreePeople, and Rancho Santa Ana Botanic Garden for a meet and greet and site visit.
September 15, 2014 – Mayor (and Metro board chair) Eric Garcetti and Councilmember Paul Koretz visit site with Mike Shull (Rec & Parks gen’l mg’r) and Shahram Kharaghani (Watershed Protection Division mg’r)
2015 – City and County of Los Angeles, Beverly Hills, Culver City and other agencies include the Greenway in the draft Enhanced Watershed Management Plan to comply with 2021 TDML compliance deadlines. Native plants installed in Expo landscaping adjacent to the Greenway land.
February 22, 2015 – Jonnathan Padilla provides concept drawings and video for Outdoor Learning Center.
October 20, 2016 – Santa Monica Bay Restoration Commission (SMBRC) recommends $2.2 million funding from Proposition 84 funds for the Greenway.
September 18, 2017 and September 28, 2017 – Proposition O Citizens Oversight Committee and Administrative Oversight Committee vote to fully fund the Greenway ($5,460,000). SMBRC's Proposition 84 grant will reimburse $2.2 million upon completion.
October 31, 2017 – Los Angeles City Council approves full funding as Proposition O project.
2018 – LA Bureau of Engineering assumes management of Prop O project and hires Atkins as consultant.
April 2018 – SMBRC grant signed.
August 2018 – Preliminary design report completed.
October/December 2018 – Community meetings.
February 2019 – Greenway construction out for bids.
September 24, 2019 – Above-ground construction begins when subcontractor (Superior Tree Care) begins removing non-native trees and other vegetation to make way for native trees and plants that will provide habitat for endemic insects and animals.