Because area ports are essential to the regional economy, I-Hung Khoo, assistant professor of electrical engineering at Cal State Long Beach (CSULB), feels it was very important to map the area ports for noise pollution.
Noise from various transportation modes including sea ports has become a major concern for environmental and government agencies in recent years, especially since the LA-Long Beach port complex is the gateway to the Pacific Rim which makes them the nation’s largest ocean freight hub and its busiest container port complex.
“All kinds of places are measured for noise such as airports and freeways but no one measured noise levels at the Port of Long Beach extensively, let alone map them, until we did,” said Khoo. “Our goal is to understand the impact of noise on the Port of Long Beach. Up to now, pollution concerns at the port have focused on exhaust but noise is as much a pollutant as truck emissions. Since the campus is so close to the Port of Long Beach, it seemed urgent to begin.”
Khoo received funding to work with Tang-Hung Nguyen, a member of the civil engineering and construction engineering department at CSULB, to create an automated port noise and activity monitoring system. This is an extension of the research Khoo and Nguyen have been working on to create noise maps for the ports of Long Beach and Los Angeles. They have received a total of $180,000 in funding from METRANS for the research.
“As the container sector of the Port of Long Beach has the highest potential for growth, the levels of noise generated by cargo transportation and handling activities are especially of interest,” explained Khoo. “The objective of our research, therefore, is to determine, using noise mapping, the level of noise generated by the cargo handling and transport activities at the container terminals of the Port of Long Beach. The benefits of noise mapping include the evaluation of noise impacts, the identification of noise hot spots, the development of noise reduction measures and the prediction of what noise impact there will be on new and future development.”
The key to noise mapping is its visual display of noise levels. To generate the noise map a computer noise model of the port was created that included the terrain and all pertinent sources of noise.
“In this way, it is possible to see the exact location of noise pollution,” said Khoo. “We wanted data about trucks, trains and cargo handling equipment activity. The result was not only a noise map of the Port of Long Beach but a map of specific sources of noise and an analysis of noise variations.”
The study concludes that the highest contributions of noise comes from trucks followed by cargo-handling activities. The contribution of railroads is not considered to be significant. The noise of container trucks traffic on the roads was deemed to be within the Caltrans/FHWA limit for developed land 500 feet from the roads and not counting the freeways. Noise from cargo-handling activities was well below the accepted level at a distance of 50 feet as stipulated by the L.A. Municipal Code for industrial equipment.
Sensitive areas include the non-industrial area east of the L.A. River and the Queen Mary, both of which were found to be within the Community Noise Exposure guidelines of the L.A. Municipal Code. The noise variation was at its highest at 8 a.m. and 1 p.m. but lowest at noon. The noise was higher on the weekdays than on the weekends. As far as monthly noise, it peaked in January and dropped to a minimum in March before rising steadily again.
“One look and the user sees the major noise contribution comes from the trucks. They have so many going in and out. The trains may be noisy but they don’t operate all the time. If they want to reduce noise, they should focus on the trucks.” said Khoo. “It can be used to predict changes in the future. Say you want to pave a new road or build a new container terminal. They can be drawn into the noise model with a description of the amount of traffic to see the effect it would have. How will these changes affect the overall noise? Say noise screening is planned. A noise wall can be drawn on the map and the effect is seen. That is the most powerful part of noise modeling. You can see noise distribution clearly on a noise map. It is both prediction and prevention.”