On-Site Sewage Disposal Program (Septic Systems)
This program deals with the permitting and inspection of on-site sewage disposal systems in Placer County. This program also involves soils testing to determine the type of on-site sewage disposal system required based on soil conditions. There are currently three types of systems that we utilize in Placer County. The decision on which type of system is to be used depends on the soil conditions in the area of a particular parcel.
Proper site conditions are a vital factor in ensuring the proper performance and treatment of On-Site Sewage, necessary in many areas of Placer County.
California State Legislature Assembly Bill (AB 885)
For Public Meeting times, and copies of the AB885 Code, and links to the State of California Water Board Site, click Here.
THREE MAIN TYPES OF SEPTIC SYSTEMS
STANDARD SEPTIC SYSTEM (Gravity Flow System):
A standard septic system consists of a septic tank and leachfield. Wastewater leaves the structure (building) and enters the first compartment of the septic tank. Heavy solids form sludge in the bottom of the tank, and grease and light material form a scum layer near the top. The clear zone between the scum layer and sludge layer flows into the second compartment of the septic tank. Effluent leaves the second compartment and flows to the distribution box at the beginning of the leachfield. From here, the effluent is distributed by gravity feed to a network of perforated pipes laid in gravel-lined trenches, which comprises the leachfield. Standard system leachlines are plumbed for serial distribution.
LOW PRESSURE DOSE SYSTEM:
A low pressure dose septic system consists of a septic tank, pump tank, and leachfield. Wastewater leaves the structure (building) and enters the first compartment of the septic tank. Heavy solids form sludge in the bottom of the tank, and grease and light material form a scum layer near the top. The clear zone between the scum layer and sludge layer flows into the second compartment of the septic tank. Heavy solids form sludge in the bottom of the tank, and grease and light material form a scum layer near the top. The clear zone between the scum layer and sludge layer flows into the second compartment of the septic tank. Effluent leaves the second compartment of the septic tank and enters the pump tank where it is stored. Effluent is pumped to the leachfield where it is distributed evenly through a network of small diameter pipes under low pressure. Low-pressure dose systems may be utilized as an alternative for some sites to mitigate the limitations associated with soils and slow permeability.
SAND FILTER SYSTEM:
A sand filter septic system consists of a septic tank, pump tank, sand filter bed, and leachfield. Wastewater leaves the structure and enters the first compartment of the septic tank. Heavy solids form sludge in the bottom of the tank, and grease and light material form a scum layer near the top. The clear zone between the scum layer and sludge layer flows into the second compartment of the septic tank. Heavy solids form sludge in the bottom of the tank, and grease and light material form a scum layer near the top. The clear zone between the scum layer and sludge layer flows into the second compartment of the septic tank. Effluent leaves the second compartment of the septic tank and enters the pump tank where it is stored. From the pump tank, effluent is periodically dosed to the top of the sand filter bed where it trickles through a layer of specialized sand. Microbes in the sand physically and bacteriologically treat the effluent. Once the effluent has passed through the sand layer it is collectd in a pump basin where it is pumped to the leachfield. Effluent is distributed evenly over the entire leachfield using a network of pipes under low pressure. Sand filter septic systems may be utilized as an alternative for some sites to mitigate the limitations associated with shallow soil depths, soils with rapid permeability, and soils with very slow permeability.
NOTE: The sand filter pretreatment system requires annual maintenance by a qualified service provider. Sand filter systems that were permitted after January 1, 2005 are all under the renewable operating permit program in which operating permits are renewed annually after the annual maintenance have been done.
Adding a Bedroom, Guest House, Second Dwelling ?
If you are planning to add a bedroom, a guest house or a second dwelling on your parcel, please call this office and speak to the District Specialist first. Your septic system may already be sized to accommodate your plans but you need to ensure that it is so, with the District Specialist. There may be instances where your septic system may need to be modified or a new system installed to accommodate your plans. When you call, please have your parcel number (example: 257-060-012-000). The parcel number works best. However, if you do not know your parcel number, then please provide the physical address of the parcel.
Adding a Swimming Pool, Pond, Second Driveway or House Addition ?
If you are planning to add a swimming pool to your property or planning to further develop your property by adding a pond, installing a second driveway or build an out building, you should be aware of the location of your on-site sewage disposal system. There are setbacks from structures to the leachfield and septic tank. Below is the table showing the setbacks.
SETBACKS
MINIMUM HORIZONTAL SEPARATION DISTANCES (SETBACKS)
|
Items Requiring Setbacks:
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From the disposal field (initial & replacement)
|
From septic tank and sand filter
|
Seepage Pits
|
|
Ground water
Public well
Private well
Other wells, excluding monitoring wells
|
150’
100’
100’
|
100’
50’
50’
|
200’
150’
150’
|
|
Surface public waters
Reservoirs, lakes
Year-round streams
and creeks
|
100’
100’
|
100’
100’
|
150’
150’
|
|
Intermittent streams, intermittent watercourses or drainage swales
|
50’
|
50’
|
50’
|
|
Spring and ponds
Upgradient
Downgradient
|
50’
100’
|
50’50’
50’
|
100’
100’
|
|
Subsurface drains
Curtain drains
Upgradient
Downgradient
Underdrains
|
15’
50’
20’
|
15’
25’
25’
|
50’
50’
50’
|
|
Water supply or irrigation canal
Flat area
Sloping area
Upgradient
Downgradient
|
50’
Clear ROW
100’
|
50’
Clear ROW
50’
|
100’
100’
100’
|
|
ROW means Right of Way
* h means the height (in ft) of the cut or escarpment as measured from the toe of the cut or escarpment vertically to the projection of the natural ground slope.
|
|
Items Requiring Setbacks:
|
From the disposal field (initial & replacement)
|
From septic tank and sand filter
|
Seepage Pits
|
|
Cuts manmade in excess of
2.5 feet (top of downslope cut)
or escarpments
|
*4 x h to
maximum of 50’
|
20’
|
* 4 x h to maximum of 50’
|
|
Property lines
Public water area
Private (domestic) well area
|
10’
*10’ or 50’
|
5’
10’
|
10’
*10’ or 75’
|
|
Foundation lines of any structure
Including garages, out-buildings,
And **paved surfaces
|
8’
|
5’
|
8’
|
|
Swimming pools
In-ground
Above-ground
|
20’
5’
|
20’
5’
|
20’
5’
|
|
Water lines (domestic or
Non-domestic)
|
10’
|
10’
|
10’
|
|
Easements
|
clear
|
clear
|
clear
|
NOTE:
(a) Unless otherwise indicated in this table, in the case of flat ground surface and when a different distance is given for upgradient and downgradient, the greater setback distance shall apply.
(b) Setbacks from streams and creeks shall be measured from back drop-off or mean yearly high water mark, whichever provides the greatest separation distance.
(c) Crossing of water lines and effluent sewer lines is prohibited.
(d) The agent shall encourage the placement of septic tanks and other treatment units as close as feasible to the minimum separation from the building foundation in order to minimize possible clogging of the building sewer.
* The 10 ft separation shall apply when adjacent parcels have been developed with structures and domestic water wells. The 50/75 ft separation shall be used when adjacent parcels have not been developed to the point indicated above. For major and minor subdivisions, disposal fields may be ten feet from interior property lines in private well areas if a well has been drilled on the affected parcel (See diagram 22) and meets County standards for an approved domestic water supply. The stricter provision stated above shall apply to parcels adjacent to the subdivision.
** There is no setback requirement for a septic tank to a paved surface. All septic tanks installed within a paved area shall be constructed in accordance with the provisions of Section 4.45.072 (including having a removable lid), and to withstand any potential load imposed from being under the paved surface.
RESOURCES
NOTE: These resources are a service to the community. They are in no way recommendations or a guarantee of quality of work.
AB885 - Onsite Wastewater Treatment Systems (OWTS) - Callifornia State Legislature Assembly Bill (AB 885), signed into Law in September 2000. California State Water Resources Control Board (State Water Board) develops, adopts, and implements statewide regulations or standards for the permitting of OWTS.
On-Site Sewage Ordinance
On-Site Sewage Program Manual
On-Site Sewage System, Septic As-built Packet
Septic Consultants List - (Septic System Design)
Septic Installers List
Advantex Service Providers List
Sand Filter Service Providers List
There are many other answers to Frequently Asked Questions available concerning septic systems.
NOTE: REMEMBER to check with the Placer County Building Department to determine if your project needs a building permit.
If you are in the incorporated areas of Placer County such as City of Auburn, Rocklin, Roseville, Lincoln, or Loomis, please check with the building department for that city.