Sound Walls 

As part of the North Coast Corridor (NCC) , Caltrans and SANDAG will construct sound walls to abate for

future noise levels associated with the completion of one Carpool/High Occupancy Vehicle (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 preliminary sound wall locations were determined and presented in the Caltrans’ Noise Abatement Decision Report (NADR) Volume 1and 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 and cataloged in a 2007 Noise Study. 


For a sound wall to be recommended for construction, it must meet criteria established by the Federal Highway Administration, which determine the level that future noise projection must approach or exceed to qualify for noise abatement measures. 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.  



Phased Construction 

Due to availability of funding, the NCC portfolio of projects and improvements – including Interstate 5 (I-5) improvements and sound walls – must be phased over time. Recommended sound walls will be constructed within three construction phases as outlined in Chapter 6 of the North Coast Corridor Public Works Plan, a comprehensive document approved by the California Coastal Commission in 2014. 



How to Find Specific Sound Wall Information 

If you would like more information regarding a proposed sound wall, please feel free to contact us at [email protected] or by following the below steps after opening upNoise 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]. Please view this sound wall mapto see the estimated construction timing of planned sound walls in the cities of Encinitas and Carlsbad.  


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