Sewer Area Study

The content of this page will provide guidance through the Sewer Area Study approval process for subdivisions, Conditional Use Permits (CUP), and single lots or any other project where Public Sewer System is proposed for ultimate public maintenance or to determine if the proposed development could be served and there’s enough capacity on the existing sewer system.




Information Lookup:

Please note, Sewer Area Study can only be prepared by a California Registered Civil Engineers.


Below are links to useful references if you have detailed questions regarding Sewer Area Study.


In order to properly process your submittal and to facilitate your plan review, please submit all of the applicable items below. It is our policy to review only completed submittals. Submittals that are not complete or do not contain the necessary references, documents, or supporting calculations may be delayed or rejected. All documents should be submitted electronically, using PDF form, to EPIC-LA. If you have already formally submitted a plan check package in the past and you wish to upload revised documents, you must resubmit to epicLA under the existing plan case. For questions regarding this checklist, please contact the appropriate plan checking unit at (626) 458-4921.


To submit your sewer area study for review, upload your report and supporting information online (link below).

Submit my report


You can pay the plan check review fees in person or online using e-check / credit card. After you have submitted your report for review, your plan checker will create a fee invoice where you can pay the fee online. Minimum deposit amounting to $2,000.00 will be required to start the review and additional charge may be added depending on the number of hours used by the plan checker towards the approval.

Paperless Submittals

We've been processing paperless plan review since 2013! Accordingly, you can submit all of your reports and supporting documents online at the link provided above. To see a typical list of all supporting documents that are required for obtaining Sewer Area Study approval, here is a Sewer Area study Submittal Checklist.

Submittal Procedure

Step by step on completing the application

Resubmittals will be required to address any corrections needed on the Sewer Area Study. Make sure to submit annotated response to plan checker comments on the report and correction list or your resubmittal may be rejected.


For each submittal, a check print showing plan check comments and a corrections list will be generated and sent to the applicant who submitted the report. These documents will address deficiencies in the report and inform you of supporting documents that needed in order to obtain Sewer Area Study approval. The following links to resubmit your plans and to some documents that you should find useful during the sewer improvement plan review:

Resubmit my report

Sewer Area Study Correction List

Agency Approvals

Before your Sewer Area Study can be approved you may need to approach various jurisdictional agencies to obtain peak discharge Q or outlet approval depending on the boundary of the sewer shed. Lastly, Los Angeles County Sanitation District Will Serve Letter is always required as part of the approval package.

What happens after Sewer Area Study Approval?

Depending on which entitlement you’re trying to get approval for, the approved sewer area study will determine if there will be mitigation or not. You may need to submit a sewer plan as part of your development or improvements of the existing sewers to have a better capacity. The findings on the approved report will be the basis on proper design of the sewer system.
The approved sewer area study shall be invalidated should there be an increase in the total number of dwelling units, an increase in the density, a change in the proposed sewer alignment, an increase in the tributary sewershed, a change in the sewer connection points, or the adoption of a land use plan or a revision to the current plan. A revision to the approved sewer area study may be allowed at the discretion of the Director of Public Works. The approved sewer area study shall remain valid for two years from the date of sewer area study approval. After this period of time, an update of the area study shall be submitted by the applicant if determined to be warranted by Public Works.

Contact Us

If you have additional questions or concerns, please contact our Final Maps & Sewer Section at (626) 458-4921.
To discuss your project with us in person, please make an appointment with us to meet at our public counter between the hours of 7:00 am and 5:00 pm, M-Th at the address below:

County of Los Angeles Department of Public Works
3rd Floor, Land Development Division
900 South Fremont Avenue
Alhambra, CA 91803

Adobe Reader