Port of Stockton
2201 W Washington St.
Stockton, CA 95203
PH 209-946-0246
FX 464-1251

Air Quality Program

The City of Stockton is located in San Joaquin County which has been identified by the Environmental Protection Agency (EPA) as a “nonattainment” area for several air pollutants i.e. particulate matter, ozone.  In laymen’s terms this means that the air quality in San Joaquin County is poor and the air is not clean enough to meet certain air quality standards set forth by the EPA.  While much of this pollution is generated by farming, agriculture and automobiles, maritime industry can be a source of pollutants as well.  An estimated one-third of vessel emissions occur while they are at berth.  While docked at the Port of Stockton vessels are required to shut off their main engines and use auxiliary diesel and steam engines to power refrigeration, lights, pumps and other functions.

The Port is continuously looking for ways to reduce air emissions as it replaces its dockside equipment with newer, clear-burning equipment. Through education and outreach to tenants and vessel operators, the Port encourages proper maintenance, operational controls and use of alternative fuels.

Program Goal

  • Reduce air pollution resulting from maritime and industrial activities at the Port

Recent Accomplishments

  • The Port has replaced four older gasoline powered trucks with new, zero-emission electric vehicles for use on the docks. The Port is also working with tenants and the San Joaquin Valley Air District to re-power and/or retrofit existing equipment with lower emitting engines for improved air quality.
  • Port tenant POSDEF operates a coal-fired power plant that generates electricity. This requires that they handle large quantities of coal which, if not handled properly, can pose a threat to air quality.  To prevent fugitive dust from leaving the site POSDEF has purchased two water canons.  These canons produce a large fine spray which reduces dust by keeping the piles damp.  The spray also “grabs” particulate matter from the air which then falls harmlessly back onto the piles. 
  • To reduce air emissions during recent dredging activities port contractors operated an electric rather than diesel-powered dredge.

Ongoing Activities

  • The Port assists ship operators with maintaining compliance while docked in Port by providing visible emissions monitoring and providing them with information on air quality standards in San Joaquin County.
  • The Port aids the San Joaquin Valley Air Quality Management District in enforcing regulations that prohibit excessive emissions from vessels that call at the Port by training Port staff to identify violators.  Every six months the Port sends employees to Visible Emissions training to be re-certified to read air emissions in order to assist with vessel compliance and reduce air impacts.

Upcoming Activities

  • The Port will be retrofitting cargo handling equipment with emissions control technology.
  • The Port’s Truck Traffic Control Plan will soon be finalized.  As part of the plan the Port will be installing signage on Rough & Ready Island directing truck traffic to the newly-completed Daggett Road Bridge.  This will ease congestion and reduce emissions in the nearby Boggs Tract neighborhood. 

Program Highlights

The Port is proud to announce that one of our tenants, Central California Traction Company, has installed an updated fuel injection system to their locomotive engines in order to maximize fuel efficiency and reduce the amount of emissions. This tenant also plans to bring in a “green goat” on a trial basis later this year to look at the feasibility of using it full time. These hybrid switchers have their electric traction motors in their axles that are powered by a large bank of custom-designed lead acid batteries. A low maintenance microturbine engine keeps the batteries automatically charged at all times, offering a 15% to 45% reduction in fuel costs during yard switching work while being much quieter and producing 80% to 90% less NOx than the standard units in operation. This technology is similar to that used in hybrid cars such as the Toyota Prius.