Her drawing of the endangered salt marsh harvest mouse is the unifying image for the Petaluma Wetlands Park and Ellis Creek Water Recycling Facility. Johanson spoke on May 7 at the Petaluma Arts Center for the opening of an exhibition of her drawings related to the wetlands park. The exhibit includes her sketches for the development of the facility, which includes treatment of wetlands and polishing ponds with a 272-acre park that restores ecosystems.

The project's polishing ponds are shaped like the mouse, and her design is expected to help put Petaluma on the map for eco-tourism, along with adjacent Shollenberger Park, which contains habitat islands for birds. There are nearly eight miles of public trails through the wetlands park area.

Although the functioning plant is complete, Johanson's vision for the site is not. Several of her concepts that will make it an eco-tourist destination have not been installed yet.

Johanson has been exploring and designing permaculture projects since 1969, long before most of us had heard the word or gave any thought to issues of sustainability. Her process is to spend time on a site, studying it and researching its history and ecology.

Originally, she was commissioned to work on only the water recycling facility. As she spent time at the site, she experienced the tides rushing in and birds feeding on the mudflats on an adjacent piece of property when the tide was out.

She felt, as did the engineering team, that the project should include a wetlands park to be linked to the water recycling facility. The city agreed, and Sandra Reed of ZAC landscape architects helped Johanson implement her ideas by providing the technical drawings.

The installation at the site traces the patterns of the salt marsh harvest mouse with interpretive signage.

Other images that can be seen in her drawings at the arts center include the Morning Glory Pools, Butterfly Pond and Mouse Tail Thin Section. These whimsical and colorful drawings contain a wealth of ecological and conceptual information. The show provides an opportunity to study the drawings of a sculptress that uses place, ecology and earth as her mediums.

The show continues through July 4.