AdministrationFreeway Noise Attenuation
Section § 215.5
This law requires the California Department of Transportation to prioritize and rank where noise barriers should be installed along freeways. The highest priority is given to residential areas developed before the freeway opened, especially if changes to the freeway have increased noise levels significantly.
When ranking, factors like current and future noise levels, traffic increases, construction costs versus noise reduction, and the number of residents nearby are considered. Cities or counties must provide proof of original residents along the freeway.
The department uses these rankings to create a construction program for noise barriers, starting with the highest priority projects. They can't prioritize new projects over those funded by cities, counties, or public agencies awaiting state reimbursement.
The state's transportation commission includes estimates of funds for noise barriers annually and for five years. If a city or county builds a noise barrier before its project reaches state funding priority, the state will reimburse the cost if standards and procedures are followed, but not exceeding what it would cost the state to build.
Section § 215.6
This law states that if a city or county pays at least one-third of the total cost for a new soundwall project that is added to the state transportation improvement program for the first time in 1992 or later, that project will be prioritized over other soundwall projects in the program. If more than one project qualifies for the top priority due to this rule, their original rankings before the acceleration will be used to determine which project is prioritized.
Section § 215.7
If a segment of a state highway is destroyed by a natural disaster and remains unusable for five years or more, the state can use its highway funds to build noise barriers on alternate highways affected by increased traffic and noise.
This is only possible if the construction gets at least 25% funding from federal relief and follows certain other regulations.
The money is essentially a loan that the state will repay through designated funds. The term "natural disaster" is defined by another specific code.
Section § 216
This law requires that noise levels from state freeway traffic or construction be measured in certain school spaces like classrooms and libraries. If these noise levels exceed certain limits (55dBA, L10, or 52dBA, Leq.), the state must implement noise-reducing measures, such as installing soundproof materials or air-conditioning, to reduce it to acceptable levels.
Noise assessments must happen during school hours and exclude non-roadway noise above legal limits. If freeway noise remains too high, schools may receive funding for converting the affected spaces for other school purposes. Additionally, if a planned freeway construction is expected to raise noise levels beyond the limit, noise control measures must be completed before or shortly after construction begins.
Priority for noise reduction efforts is given to schools built following certain legal standards. The law explains technical sound-related terms like dBA, L10, and Leq.
Section § 216.1
This section defines 'spaces used for pupil personnel services' as rooms primarily used for activities like counseling or testing with students present.
Section § 216.5
This law requires the California Department of Transportation to build a demonstration noise barrier using rice straw, but only if certain conditions are met. First, the rice straw barrier must be approved and listed as an option by the department. Then, funding must be secured by the rice straw system's manufacturer to cover any extra costs. Additionally, a suitable construction site must be selected that meets all necessary safety and environmental standards. If these conditions aren't met, the project doesn’t have to proceed. The department needs to report to the Legislature on the implementation by a set deadline.