The residential street along Chynoweth Avenue was rebuilt to remove excess lane width. This project involved installing a raised median and constructing new bioretention areas to treat stormwater runoff. In total, the project created approximately 5,600 square feet of bioretention rain gardens, installed approximately 19,500 square feet of porous asphalt, planted 36 large canopy trees, and eliminated approximately 40,000 square feet of existing impervious pavement and a barren dirt median that previously contributed sediment to the storm drain system. Traffic and pedestrian safety improvements such as street lamps, crosswalks and bike lanes also were installed as a part of the project.

The specific design features of the Chynoweth Avenue Green Streets Project include:

  • Rain gardens
  • Porous asphalt sidewalk
  • Mulched median planted with large canopy trees

Water Quality Benefits:

  • Major source of sediment eliminated
  • Pollutants, such as oil and grease from cars, filtered from runoff on site

Neighborhood Improvement Benefits:

  • New pavement with proper drainage
  • Reduced runoff to storm sewer
  • Cleaner streets
  • Traffic calming
  • Reduced urban heat island effect
  • Increased green space

Protecting Our Watersheds

A watershed is a land area that drains water into a creek, river, lake or bay. The Guadalupe Watershed is one of the largest watersheds in Santa Clara County and has been identified as a priority watershed due to poor water quality from urban runoff and other pollutants. The Chynoweth Avenue Green Streets are located near the Guadalupe River, which flows through San José and into the San Francisco Bay. This project showcases a stormwater management retrofit that benefits the community and the watershed.

Chynoweth Avenue Green Streets is a joint project of:

Department of Water Resources – Provided $2 million of Proposition 84 Integrated Regional Water Management Grant Program funds for planning, design and construction.

City of San José – Provided project design and engineering, construction management and inspection, grant administration, and pre- and post-project water quality monitoring.

Funding for this project was provided in part through an agreement with the Department of Water Resources.