Sound Walls 

Caltrans and SANDAG will construct sound walls to abate for

future noise levels associated with the completion of one Carpool/HOV Lanes in both directions on Interstate 5 (I-5). Sound walls abate noise by blocking, absorbing, and/or redirecting noise away from residences adjacent to freeways. 

Recommended sound wall locations were determined and presented in the Caltrans Noise Abatement Decision Report (NADR) Volume 1 and Volume 2, a component of the Interstate 5 (I-5) North Coast Corridor (NCC) Final Environmental Impact Report/Environmental Impact Statement. The NADR uses sound data that was collected by Caltrans in a 2007 Noise Study. A new Noise Study will begin in 2023 that analyzes the decisions of the 2007 Study based on current noise levels.


For a sound wall to be recommended for construction, it must meet criteria established by the Federal Highway Administration.. Noise abatement measures must also reduce the future noise levels by a minimum of 5 decibels to be preliminarily recommended for construction in the project’s NADR. 


Learn more about the Build NCC sound wall process in this sound wall presentation.  



How to Find Specific Sound Wall Information 

If you would like more information regarding a proposed sound wall, contact us at [email protected] or by following the below steps after opening up Noise Abatement Decision Report (NADR) Volume 1.


1.) Go to page 35 to see a map of each Segment of construction. 

2.) Zoom in to the map to find the street name closest to your residence. For example, if you live between Lomas Santa Fe and Manchester Drive, you are Segment 7. If you live closer to Lomas Santa Fe, you are Sheet 22 of Segment 7. If you live closer to Manchester Avenue, you are Sheet 24 of Segment 7. If you live in the middle of these streets, you are most likely Sheet 23 of Segment 7.

3.) If you fall between Segments 1-10, please scroll to your segment within the Noise Abatement Decision Report (NADR) Volume 1. For shortcuts, please click ctrl+F and type in your Segment number (ex. “Segment 7”)

4.) If you fall between Segments 11-22, please open the Noise Abatement Decision Report (NADR) Volume 2. Once you open this document, please scroll to your segment. For shortcuts, please click ctrl+F and type in your Segment number (ex. “Segment 11”).

5.) Once you are in your Segment section, please find your sound wall, or “Noise Barrier,” information by referencing your sheet number. Using our previous example, if you live closer to Lomas Santa Fe, you are Sheet 21 of Segment 7. Information regarding this sound wall will be found on page 119-120. 



If you are having trouble searching the documents or if you still have questions regarding a planned sound wall, please contact us at 844-NCC-0050 or [email protected]. 


The NADR uses sound data that was collected by Caltrans and cataloged in a 2007 Noise Study. You can view the supporting appendices for this Study below:

sandaga