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Past Events (1917)

Date range
June 13, 2026
Saturday
June 7, 2026
Sunday
  • Naturalist Michael Marchiano- Butterflies

  • Jun 7, 2026 from 1:00pm to 2:00pm
  • Location: Rodgers Ranch Heritage Center, Pleasant Hill
  • Description:

    Our county has over 75 species of butterflies that can be found throughout the year. Join naturalist Michael Marchiano for a lecture and presentation showing photos of over 60 of them. Learn the host plant for their catepillars and many other fascina

  • Created by: Sustainable Contra Costa
June 6, 2026
Saturday
  • East Bay Green@Home Tour 2026

  • Jun 6, 2026 from 11:00am to 3:00pm
  • Location: Various East Bay Homes
  • Description:

    Acterra is proud to present the East Bay Green@Home Tours 2026! This is a FREE, community-powered event that invites the public to explore innovative, electrified homes. Explore homes throughout Alameda and Contra Costa Counties, ranging from new con

  • Created by: Sustainable Contra Costa
 
  • Tri-Valley Polluters Pay Town Hall

  • Jun 6, 2026 from 10:00am to 12:00pm
  • Location: Wells Middle School, Dublin
  • Description:

    Big Oil and gas corporations have been profiting while our communities pay the price. But together, we can make a difference! Join us in Dublin on June 6 for the Tri-Valley Polluters Pay Town Hall—an energizing morning of inspiration, action, and com

  • Created by: Sustainable Contra Costa
 
  • East Bay Public Gardens Open House

  • Jun 6, 2026 from 10:00am to 1:00pm
  • Location: Various East Bay Gardens
  • Description:

    Discover the beauty and benefits of water‑wise gardening! Visit a nearby participating garden for expert tips, tours, and resources. Learn about attracting pollinators, blooming native plants, growing food, large and small garden designs, building he

  • Created by: Sustainable Contra Costa
May 9, 2026
Saturday
  • Bioregional Regeneration Bay Delta unConference

  • May 9, 2026 from 9:00am to 5:00pm
  • Location: Oakstop, 2323 Broadway, Oakland
  • Description:

    This is the 4th Bay Delta Bioregional Regeneration Unconference. Each gathering has deepened our network and sparked new collaborations across the region - and we keep coming back because something real happens in these rooms.

    At previous unconferenc

  • Created by: Sustainable Contra Costa
 
  • Ridge-to-Ridge Challenge

  • May 9, 2026 from 9:00am to 1:00pm
  • Location: Walnut Creek Open Space, Shell Ridge
  • Description:

    The Ridge-to-Ridge Challenge is an annual fundraiser supporting Sustainable Contra Costa and its youth program, Sustainable Leaders in Action (SLIA). Each year, high school and college students collaborate to raise awareness about climate issues and

  • Created by: Sustainable Contra Costa
May 3, 2026
Sunday
  • Naturalist Talk - Common Native Local Trees and Shrubs

  • May 3, 2026 from 1:00pm to 2:30pm
  • Location: Rodgers Ranch Heritage Center, Pleasant Hill
  • Description:

    Learn fascinating facts about our common oak trees, our only native Maple and the beautiful red barked Madrone. Learn to recognize and name ceanothus, manzanitas, chamise, sages and more that make up the foliage covering our hillsides.

    FREE for RRH

  • Created by: Sustainable Contra Costa
May 2, 2026
Saturday
  • Concord Spring Fest

  • May 2, 2026 from 12:00pm to 7:00pm
  • Location: Todos Santos Plaza, Concord
  • Description:
    The 5th annual Bay Area SpringFest is coming to Todos Santos Plaza in charming, historic Downtown Concord SATURDAY, May 2, celebrating spring in the Bay Area with music, food, children's activities and exhibitors featuring arts & crafts, jewelry, art
  • Created by: Sustainable Contra Costa
 
  • Free Virtual Worm Composting Workshop

  • May 2, 2026 from 10:00am to 12:00pm
  • Location: Online webinar
  • Description:

    Worm castings make great fertilizer! In this free online workshop you’ll learn how to create your own worm compost. Vermicomposting (“vermi” is Latin for “worm”) is the process of using worms to break down organic food waste into nutrient-rich soil.

  • Created by: Sustainable Contra Costa
May 1, 2026
Friday
  • Greywater Design Mastery course (online)

  • May 1, 2026 from 8:00am to 10:00am
  • Location: Online webinar
  • Description:

    Design a professional greywater system for your home (or your client’s) to save water and grow a beautiful landscape.

    Greywater Design Mastery is a comprehensive greywater program to teach you how to design professional, well-functioning greywater ir

  • Created by: Sustainable Contra Costa
April 27, 2026
Monday
  • Too Good to Waste: "Toilet Rewind"

  • Apr 27, 2026 from 12:00pm to 3:00pm
  • Location: Online webinar
  • Description:

    Get ready to peek into the fascinating and little-known past when city dwellers kept their local waters clean by recycling and reusing poop. We’ll visit sand toilets of ancient Egypt, earthen-plaster toilets of the Mali empire, nutrient recycling sys

  • Created by: Sustainable Contra Costa
April 26, 2026
Sunday
  • Earth Day 2026 in Lafayette

  • Apr 26, 2026 from 11:00am to 2:00pm
  • Location: Lafayette Plaza Park
  • Description:

    Sustainable Lafayette will be hosting a free Earth Day Festival to celebrate our beautiful town and local environment. Lafayette Earth Day will be April 26, 11am-2pm, at the Plaza Downtown (3530 Plaza Way). Activities will include family-friendly act

  • Created by: Sustainable Contra Costa