URBAN ECOLOGY
Nature surrounds us, even in cities. Urban Ecology means sustaining nature in our cities. This includes creating neighborhood rain gardens with native plants that support pollinators and absorb stormwater, encouraging the planting of native trees to provide shade and habitat, and restoring the banks of local creeks that flow through our cities.
GREEN STORMWATER INFRASTRUCTURE
Have you ever noticed how quickly our urban creeks flood after rain to only quickly dry up soon after? This is caused by hard, impermeable surfaces like asphalt roads, parking lots, cement sidewalks, and buildings that prevent rainwater from soaking into the ground. Instead of the earth slowly filtering and feeding water to our creeks year round, rain that falls on cities flows across our urban landscape, picking up harmful pollutants along the way, and that stormwater is diverted through storm drains into creeks and eventually to the ocean.
Green stormwater infrastructure addresses this problem by intercepting stormwater and allowing it to soak into the ground. This has multiple benefits including water quality, flood reduction, groundwater recharge, and water conservation.
Rain Barrels
Rainwater catchment systems such as rain barrels or cisterns can be a great way to save water and reduce stormwater runoff. The water stored in the rain barrels can be used to irrigate landscaping.
Grassroots Ecology has installed demonstration rain catchment systems at these public spaces:
Peninsula Conservation Center: Two 55 gallon wine barrels, 500 gallon cistern feeding into rain garden
Gamble Garden: 260 gallon cistern, 55 gallon wine barrel
McClellan Ranch Preserve: Two 55 gallon wine barrels
Pearson-Arastradero Preserve: Eight 80 gallon barrels daisy-chained together
Redwood Grove Nature Preserve: 55 gallon wine barrel feeding into a rain garden
We are also working with Climate Resilient Communities and Fresh Approach to install 25 rain gardens and barrels for homeowners in East Palo Alto <more info here>.
There are many resources available to help you install a rain barrel at home. The Bay Area Water Supply and Conservation Agency (BAWSCA) has rebates available for purchased rain barrels in several participating Bay Area cities. Click here to learn more about these rebates.
Rain Gardens
Our native plant rain gardens slow and filter stormwater runoff and enhance urban habitat for pollinators and other wildlife. Our gardens feature bioswales and retention areas which direct water through the garden and into the soil.
Visit one of our rain gardens for inspiration in your own space!
Southgate Bioretention Basins
In partnership with the City of Palo Alto and the Santa Clara Valley Water District, revitalizing bioretention basins in the city’s Southgate neighborhood to improve native habitat and stormwater filtration in an area once prone to flooding. Stormwater flows into these basins through inlets, or openings cut out from the curb, and the plants and soil within the plots help to filter pollutants in urban stormwater runoff before absorbing water into the soil.
We are installing a range of plants from our Native Plant Nursery that can withstand temporary flooded conditions in winter as well as dry conditions in summer months. High efficiency irrigation systems are also being installed to help establish the new plants, and aid them through the dry months.
Before
After planting in 2020
2022
NATURE IN THE CITY
Pollinator Gardens
Habitat loss, pollution, invasive species, and climate change are contributing to the rapid decline of insect species all over the planet. The monarch butterfly population alone has decreased 80% since the 1990s. Insects provide many services that are essential to our survival—from pollination to pest control—and are a critical food source for birds, fish, amphibians, and other wildlife.
Our pollinator gardens provide a breadth of biodiversity to support native pollinators in our area, especially city neighborhoods! Visit one of our gardens to learn what kinds of plants you can incorporate in your space to support the pollinators:
Learn how to grow native plants and where to get them:
Native Street Trees
We advocate to local cities to incorporate more native tree species into their landscapes. Historically, native California trees, mainly oaks, covered most of our local landscape. Now, they only account for about 5% of city trees. Native species are essential habitat sources for thousands of different mammals, birds, and insects. If we lose our native trees, insects and the rest of the ecosystem will collapse.
Without trees, urban areas experience the heat island effect where heat is absorbed by built hardscapes, increasing the urban areas temperature compared to nearby rural areas. Evergreen trees, such as Coast Live Oaks, also remove toxins from the rain before it reaches our creeks and baylands. Adding trees to urban areas can combat the heat island effect and improve water quality while also supporting local wildlife.
Chart source: San Francisco Estuary Project, Reoaking Silicon Valley, 2017
