A septic layout requires experience and skill.  The Department of Environmental Health (DEH) Land Use  Division has a very rigid approach to layout reviews and demand information at a level of precision so as to avoid risky decisions.  The DEH is the ultimate decision maker on what is acceptable.  The inspectors are detail oriented and very observant.

Rarely does a layout get approved on the first submittal regardless of the level of excellence on the part of the one who does the work.  There are reasons for this, but beyond the scope of comment on this site.

The County of San Diego maintains a website with guidelines and supportive information at  It is very helpful in a general sense.  

Some of the inspectors do not approach a site from a professional perspective, but are more like a technician with a check-off list.  This is understandable when they are young in the industry and do not want to take much risk with issues of subjective judgment.  On the other hand, they eventually see the gestaldt and mature to a problem solving approach.  I usually try to be a good listener and keep my opinions to myself .  I advocate strongly when they are clearly in error and back off on issues that are worthy of no disagreement, despite one’s opinion.  It is important to put yourself in the other position and evaluate without bias.  After all, if an opinion has merit, then it should be respected.

The following list of layout attributes and constructs for a septic system layout .  Not all layouts require all this information, but the list covers what must must be considered when doing a site assessment.  The order of information can vary with efficiency and opportunity.

Layout Constructs and Preparation According to Jayhawk Consultants.

Basic Information to prepare for doing a septic layout  include the following:


Determine the preferred location of the dwelling, a description of proposed grading , number of bedrooms and any  proposed plans for a second dwelling, guest house, swimming pool, workshop, barn, corrals, well sites or other proposed structures.


 Determine the preferred route for a driveway.


Determine the Assessors Property Description. (Book, Page and Lot Number) .Usually, the owner or contractor provides this information as found on the property tax statement; otherwise, it can be determined by cross reference of the address at the County Assessor’s Office.  Title Companies will also provide this information and if you wish to drive to San Diego and wait an hour or two, you can get this information from the County Planning Department.  Another option is to merely call the County Assessor at (619) 236-3711 or  (858) 505-6262.


Determine if the property has a certification by the Department of Environmental Health (DEH).   This is sometimes confused with a “legal lot basis”. but it is not the same.  The objective is to determine if the property has been approved by DEH and assigned requirements for a septic disposal system.

This “certification” can be according to a subdivision, parcel map, lot split, boundary adjustment, certificate of compliance or a percolation test referenced to a “Grant Deed Lot” acceptable to the Department of Planning and Land Use.  This is generally any deeded property with no lot line changes since February 2, 1972; (there are some exceptions ; an example is a lot surrounded by lots with certification). This finding is important, because some lots may actually have sewer available ,and if this is so, then a septic system is not an option (except in rare cases). The easiest way to obtain this information is to inquire at the DEH office nearest the property location.  Another source is a Title Company. The most reliable source is the DPLU.

Note: This research must be tempered with care.  When I am advised by DEH of no legal lot certification, I do noit accept the advice.  Many times, the property has a certification which is unknown to DEH staff and as a concurrence, my policy is to personally “double-check” with the DPLU.  The County Assessor documents are also not reliable for older certifications such as Lot Splits.  Many of the older “Record of Survey” documents had DEH letters with a “certification” for a septic system.  Finding of these letters is rare.  Perhaps they have been misplaced.

To the credit of DEH, they do their best to locate a “legal lot basis” and if they are successful, then your mission is complete.  Otherwise…always double check!


Research the DEH records for any useful information. This should be done at the San Marcos DEH office if the property is in the “North County and Pauma-Palomar area”; at the El Cajon Office if in the “East County”(including Poway and Ramona).


Go to the internet and observe an aerial view of the property on websites such as “Google Earth” and “Microsoft Vision View”.


Make a site assessment of the property and observe for attributes which can impact a layout design.


Contact “Zoning Information” at the County Department of Planning and Land Use  (DPLU) for construction setback information..  The telephone number for  Zoning  is 1-888 267-8770.  Be prepared to tell them the APN and they will advise you of construction setbacks. An optional source for this information is the County Website: however, the sequence is confusing and nearly impossible to figure out (at least to me, anyway). Give it a try…good luck!


Research the records of the water district for location of any easements and existing waterlines. This should be done regardless of whether the property is on a private well or is served by a water company.  Layouts require a certification  which advises “all waterline locations within 20 feet of the property boundaries are shown on the layout”.

This research should also include a conclusive knowledge of any local aqueduct routes, water district pipelines from the aqueduct and flumes.

l Information to Show on a Layout Draft ( 8 ½ ” X 11″ or 11″ X 17″


Homes site with number of bedrooms and elevation. (Make sure the construction setbacks are considered).


Driveway trend, parking and a fire vehicle turnaround. that meets standards of the local fire marshall


Show contours on a useful scale and with elevations. (usually the 25 foot distance separation).  My layouts are usually a “fifty scale” (1 inch = 50 feet.)  A hundred scale should be avoided and a 200 scale is worthless.  On large lots, it is useful to reference a larger scale as a “Detail Plat” and show the relevant portion of the property.  A “Key Map” can be used to show the total property for an overview. The latter can be a 100 scale and if necessary a 200 scale as a last resort.  The issue is merely to provide a scale that can be useful and accurate.


Provide a “North Arrow” and a scale reference.


Per Cent Slope in the leach field area.


Location of the septic tank (The tank should be located so as to be accessible for maintenance- a rule of thumb is within 80 feet of where a pumper truck can park.


Show all tight lines and specify Schedule 40 PVC or equivalent when crossing a traveled way, driveway or any other traffic area.


Show a location for overflow siphons.  (I recommend  placing them at lest ten feet from the end of a leach line so they are not impacted by potential sludge accumulation and extreme hydraulics).


Show all traveled ways and grove roads.


Show the location of all public water lines. A “water line statement” is also required.


Show all drainage patterns and the recommended setback zone.


Show all vertical cut banks, indicate the height and the setback distance.

These boys are a big help and help their old uncle out so he can nap while they do the layout work. They know all my layout secrets and have a perfect record with DEH approvals.


Show all cuts and fill.


Show the route of utilities. If electricity is by overhead power line connection, show the trend of the power line.


Show the location of power poles and anchors. Setbacks to leach lines must also be shown if in the vicinity of the disposal system.  Written permission from San Diego Gas and Electric (SDG&E ) is required if any leach field has encroachment or is nearby.


Provide a “location map” with a Thomas Brothers Page and coordinate reference.


Provide the name of the owner, a contact phone number and mailing address.


Provide the Assessors Parcel Number (Book,Page and Lot).


Show any significant rock outcroppings and locations of significant boulders.


Show the location of any percolation testing and soil borings if known. If applicable, reference to the percolation test on the layout and provide a copy so the DEH can compare the location of testing with the proposed layout.


 Show the names of any streets


Provide the lot dimensions for each linear segment of the property.


Indicate the number of bedrooms.


Show any adjacent offsite grading and any relevant setbacks.


Show the location of the water meter and indicate the name of the purveyor. (If on a well, show the location and route of the supply line and location of the storage tank).


Show the location of any wells on the property and within 100 feet of any property line.


Show any area of 60% slope that abuts a leach field. Provide a 5:1 setback to the height of the slope range as if it was a cut bank.


Any easement known to impact the leach field area.  An example could be a future road alignment. Another is the utility easements recorded by SDG&E.  Contemporary parcel maps and subdivision lots have easements for “open space” and related restrictive aras that require careful assessment of the recorded conditions of the map or consult with the DPLU.


Other attributes may be required on a “site specific basis” such as specific setbacks.  One example is a minimum twenty-five foot setback to a public road within a water district. Another example is a “Right of Way” for a county road which is part of the circulation element.  This will require clearance from the Department Public Works. (DPW).  If the road is under the jurisdiction of the State of California, it will be necessary to have the layout cleared by the California Department of Transportation. (CalTrans).

If your are weary of doing this yourself, contact Larry Newcomb ( and he will do a layout and add his name and contact information to the layout., do all the follow-up and resolve any questions.

NOTE: Special design considerations are necessary if the site involves an aqueduct, crossing a public waterline, a non-gravity system (pump chamber and surge tank with engineering), and slopes in excess of 25%..

The following layout plat is from the DEH Guidelines.  It is a good model for general information.  I did this layout for the County many years ago.  Layouts were simple then.  Anyway the layout still persists.  Don’t ask me why!