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This is the exact text of the current standard, without any changes or comments (later we'll post a fully annotated version with interpretation and suggested improvements here and in our Builder's Grey Water Guide (book)).
Official PDF of same exact language from HCD web site
Official PDF of same exact language copied here from HCD web site 7/7/2010
INTRODUCTION
The emergency graywater regulations, which added Chapter 16A "Nonpotable Water Reuse Systems" into the 2007 California Plumbing Code, were approved by the California Building Standards Commission (CBSC) on July 30, 2009. The emergency regulations were subsequently filed with the Secretary of State on August 4, 2009, effective immediately upon filing.
In compliance with the Administrative Procedure Act, HCD prepared a “Certificate of Compliance” confirming the completion of the rulemaking process, which included a 45-day public comment period, a subsequent 15-day comment period, a Final Statement of Reasons and the Final Express Terms.
CHAPTER 16A NONPOTABLE WATER REUSE SYSTEMS
Intent
This part is applicable to occupancies under the authority of the Department of Housing and Community Development as specified in Section 108.2.1.1 and is intended to:
Note: It is not the intent of this section to require that all graywater must be handled by an irrigation field or disposal field. It is acceptable for excess graywater to be diverted to the building sewer through the overflow required pursuant to Section 1609A.O (E).
(C) No graywater system or part thereof shall be located on any lot other than the lot that is the site of the building or structure that discharges the graywater, nor shall any graywater system or part thereof be located at any point having less than the minimum distances indicated in Table 16A-1.
Exception: When there exists a lawfully recorded perpetual and exclusive covenant to an easement appurtenant and right-of-way between adjoining land-owners of two or more contiguous lots to discharge graywater from one lot to an adjoining lot.
(D) No construction permit for any graywater system shall be issued until a plot plan with appropriate data satisfactory to the Enforcing Agency has been submitted and approved. When there is insufficient lot area or inappropriate soil conditions to prevent the ponding or runoff of the graywater, as determined by the Enforcing Agency, no graywater system shall be allowed.
Exception: A construction permit shall not be required for a clothes washer system which does not require cutting of the existing plumbing piping provided it is in compliance with Section 1603A.1.1.
Clothes Washer System. A graywater system utilizing only a single domestic clothes washing machine in a one- or two-family dwelling.
Complex System. Graywater systems that discharge over 250 gallons (947 L) per day.
Disposal Field. An intended destination for graywater including but not limited to a mulch basin or receiving landscape feature, graywater leach field, or other approved method of disposal.
Graywater. Pursuant to Health and Safety Code Section 17922.12, "graywater" means untreated wastewater that has not been contaminated by any toilet discharge, has not been affected by infectious, contaminated, or unhealthy bodily wastes, and does not present a threat from contamination by unhealthful processing, manufacturing, or operating wastes. "Graywater" includes but is not limited to wastewater from bathtubs, showers, bathroom washbasins, clothes washing machines, and laundry tubs, but does not include wastewater from kitchen sinks or dishwashers.
Graywater System. A system designed to collect graywater and transport it out of the structure for distribution in an Irrigation or Disposal Field. A graywater system may include tanks, valves, filters, pumps or other appurtenances along with piping and receiving landscape.
Irrigation Field. An intended destination for graywater in the receiving landscape including but not limited to a drip irrigation system, mulch basin, or other approved method of dispersal for irrigation purposes.
Mulch. Organic waste material including but not limited to leaves, prunings, straw, pulled weeds and wood chips. Mulch shall be permeable enough to allow rapid infiltration of graywater.
Mulch Basin. A type of irrigation or disposal field filled with mulch or other approved permeable material of sufficient depth, length and width to prevent ponding or runoff. A mulch basin may include a basin around a tree, a trough along a row of plants or other shapes necessary for irrigation or disposal.
Receiving Landscape. Includes features such as soil, basins, swales, mulch, and plants.
Simple System. A graywater system serving a one- or two-family dwelling with a discharge of 250 gallons (947 L) per day or less. Simple systems exceed a clothes washer system.
Treated Graywater. Nonpotable water collected and treated on-site suitable for direct beneficial use.
A written construction permit shall be obtained from the Enforcing Agency prior to the erection, construction, reconstruction, installation, relocation or alteration of any graywater system that requires a permit.
Exception: A construction permit shall not be required for a clothes washer system which does not
require cutting of the existing plumbing piping provided it is in compliance with Section 1603A.1.1.
1603A.1.1 Clothes Washer System. A clothes washer system in compliance with all of the following is exempt from the construction permit specified in Section 108.4.1 and may be installed or altered without a construction permit:
1603A.1.2 Simple System. Simple systems exceed a clothes washer system and shall comply with the following:
Table 1603A.1.4 – Construction Permit Requirements
| Type of System | Permit Requirements |
| Clothes Washer System | No construction permit required if conditions in Section 1603A.1.1 are met. |
| Simple System | Permit and plans required unless exempted by Enforcing Agency. |
| Complex System | Permit and plans required unless exempted by Enforcing Agency. |
| Treated Graywater | Permit and plans required unless exempted by Enforcing Agency. |
Graywater systems for which a construction permit is required may be subject to submittal of plans and details of the proposed graywater system necessary to ensure compliance with the requirements of this chapter. Identification of the groundwater level and soil absorption qualities at the site shall be included in the plans or provided to the Enforcing Agency.
Exception: The Enforcing Agency may waive the requirement for identification of groundwater level
and/or soil absorption qualities based on knowledge of local conditions.
1604A.1 Groundwater Depth. Verification of ground water levels which exceed three (3) vertical feet (915 mm) from the deepest irrigation or disposal point of the proposed graywater system shall not be required.
Note: The absence of groundwater in a test hole three (3) vertical feet (915 mm) below the deepest irrigation or disposal point shall be sufficient to satisfy this section unless seasonal high groundwater levels have been documented to rise to within this area.
(A) Inspection. A graywater system for which a construction permit is required shall be subject to inspection by the Enforcing Agency and such construction or work shall remain accessible and exposed for inspection purposes until approved.
At the time of final inspection, an operation and maintenance manual shall be provided. Directions shall indicate the manual is to remain with the building throughout the life of the system and upon change of ownership, the new owner shall be notified the structure contains a graywater system
(A) Single Family Dwellings and Multi-Family Dwellings. The graywater discharge for single family and multi-family dwellings shall be calculated by estimates of graywater use based on water use records, calculations of local daily per person interior water use, or the following procedure:
Showers, bathtubs 25 GPD (95 LPD)/occupant and wash basins
Laundry 15 GPD (57 LPD)/occupant
3. The total number of occupants shall be multiplied by the applicable estimated graywater discharge as provided above and the type of fixtures connected to the graywater system.
(B) Daily Discharge – Graywater systems using tanks shall be designed to minimize the amount of time graywater is held in the tank and shall be sized to distribute the total amount of estimated graywater on a daily basis.
Exception: Treated graywater systems when approved by the Enforcing Agency.
1607A.0 Required Area of Irrigation or Disposal Fields. Irrigation or disposal fields may have one or more valved zones. Each zone must be of adequate size to receive the graywater anticipated in that zone. No irrigation or disposal field shall extend within three (3) vertical feet (915 mm) of the highest known seasonal groundwater, or to a depth where graywater contaminates the groundwater, ocean water or surface water. The applicant shall supply evidence of groundwater depth to the satisfaction of the Enforcing Agency.
Note: The absence of groundwater in a test hole three (3) vertical feet (915 mm) below the deepest irrigation or disposal point shall be sufficient to satisfy this section unless seasonal high groundwater levels have been documented to rise to within this area.
Exception: Irrigation fields in compliance with Section 1611A.2, which only utilize drip type emitters.
(C) When a percolation test is required, no graywater system shall be permitted if the test shows the absorption capacity of the soil is unable to accommodate the intended discharge of the proposed graywater system. Exception: The Enforcing Agency may waive the requirement for percolation tests based on knowledge of local conditions or accept other testing methods.
Graywater systems shall comply with Sections 1610A.1 through 1610A.3.
1610A.1 Pipe Materials. Graywater pipe, valves and fittings shall conform to the requirements of Sections 604.0, 605.0 and 606.0.
1610A.2 Identification. Graywater distribution piping upstream of any connection to an irrigation or disposal field or a distribution valve shall be identified with the words "CAUTION: NONPOTABLE WATER, DO NOT DRINK." Marking shall be at intervals not to exceed five (5) feet (1,524 mm).
1610A.3 Valves. All valves shall be accessible. A backwater valve installed pursuant to this code shall be provided on all tank drain connections to the sanitary drain or sewer piping.
Irrigation fields, disposal fields and mulch basins used in graywater systems shall comply with this section. Graywater systems may contain either a irrigation field or a disposal field or a combination of both. This section is not intended to prevent the use of other methods of graywater irrigation or disposal approved by the Enforcing Agency.
1611A.1 Mulch Basin A mulch basin may be used as an irrigation or disposal field. Mulch basins shall be sized in accordance with Table 16A-2 and of sufficient depth, length and width to prevent ponding or runoff during the graywater surge of a clothes washer, bathtub or shower. Mulch must be replenished as required due to decomposition of organic matter. Mulch basins will require periodic maintenance, reshaping or removal of dirt to maintain surge capacity and to accommodate plant growth and prevent ponding or runoff,
1611A.2 Irrigation Field. The provisions of this section are not intended to prevent the use of any appropriate material, appliance, installation, device, design or method of construction. If an alternate design is not available, the following provisions may be used as guidance in the design of a graywater irrigation field:
(1)Filters used in graywater irrigation systems shall be as specified by the manufacturer’s installation instructions for the design flow rate and intended use. The filter backwash and flush discharge shall be contained and disposed of into the building sewer system, septic tank or, with approval of the Enforcing Agency, a separate mini-leachfield sized to accept all the backwash and flush discharge water. Filter backwash water and flush water shall not be used for any purpose. Sanitary procedures shall be followed when handling filter backwash and flush discharge or graywater.
1611A.3 Disposal Field. The provisions of this section are not intended to prevent the use of any appropriate material, appliance, installation, device, design or method of construction. If an alternate design is not available the following provisions may be used as guidance in the design of a graywater disposal field:
Exception. Manufactured leaching chambers shall be installed in compliance with the manufacturer’s installation instructions.
(C) Disposal fields shall be constructed as follows:
(See chart below)
| Minimum | Maximum | |
|---|---|---|
| Number of drain lines per valved zone1 | 1 | — |
| Length of each perforated line1 | — | 100 ft. (30,840 mm) |
| Bottom width of trench1 | 12 in. (305 mm) | 24 in. (610 mm) |
| Spacing of lines, center to center1 | 4 ft. (1219 mm) | — |
| Depth of earth cover of lines | 2 in. (51 mm) | — |
| Depth of filter material cover of lines | 2 in. (51 mm) | — |
| Depth of filter material beneath lines1 | 3 in. (76 mm) | — |
| Grade of perforated lines | level | 3 in./100 ft. (2 mm/m) |
1 Manufactured leaching chambers shall be installed in compliance with the manufacturer’s installation instructions.
(D) When necessary on sloping ground to prevent excessive line slopes, disposal lines shall be stepped or installed on the contour lines of the slope. The lines between each horizontal leaching section shall be made with approved water-tight joints and installed on natural or unfilled ground.
| Minimum Horizontal Distance Required From: | Tank | Irrigation Field | Disposal Field |
| Feet/mm | Feet/mm | Feet/mm | |
| Building structures1 | 5 (1,524 mm)2 | 2 (610 mm) | 5 (1,524 mm) |
| Property line adjoining private property | 5 (1,524 mm) | 1.5 feet (458 mm) | 5 (1,524 mm) |
| Water supply wells3 | 50 (15,240 mm) | 100 (30,480 mm) | 100 (30,480 mm) |
| Streams and lakes3 | 50 (15,240 mm) | 100 (30,480 mm)4,5 | 100 (30,480 mm)4 |
| Sewage pits or cesspools | 5 (1,524 mm) | 5 (1,524 mm) | 5 (1,524 mm) |
| Sewage disposal field | 5 (1,524 mm) | 4 (1,219 mm)6 | 4 (1,219 mm)6 |
| Septic tank | 0 (0) | 5 (1,524 mm) | 5 (1,524 mm) |
| Onsite domestic water service line | 5 (1,524 mm) | 0 (0 mm) | 0 (0 mm) |
| Pressurized public water main | 10 (3,048 mm) | 10 (3,048 mm)7 | 10 (3,048 mm)7 |
1 Building structures does not include porches and steps, whether covered or uncovered, breezeways, roofed porte cocheres, roofed patios, carports, covered walks, covered driveways, and similar structures or appurtenances. 2 Underground tanks shall not be located within a 45 degree angle from the bottom of the foundation, or they shall be designed to address the surcharge imposed by the structure. The distance may be reduced to six (6) inches (153 mm) for aboveground tanks when first approved by the Enforcing Agency. 3Where special hazards are involved, the distance required shall be increased as directed by the Enforcing Agency. 4These minimum clear horizontal distances shall also apply between the irrigation or disposal field and the ocean mean higher hightide line.5The minimum horizontal distance may be reduced to 50 feet (15,240 mm) for irrigation fields utilizing graywater which has been filtered prior to entering the distribution piping.
6 Plus two (2) feet (610 mm) for each additional foot of depth in excess of one (1) foot (305 mm) below the bottom of the drain line. 7For parallel construction or crossings, approval by the Enforcing Agency shall be required.
Table 16A-2 Design Criteria of Six Typical Soils
| Type of Soil | Square Feet | Gallons | Square Meters | Liters |
|---|---|---|---|---|
| Minimum square feet of irrigation/leaching area per 100 gallons of estimated graywater discharge per day | Maximum absorption capacity in gallons per square foot of irrigation/leaching area for a 24-hour period | Minimum square meters of irrigation/leaching area per liter of estimated graywater discharge per day | Maximum absorption capacity in liters per square meter of irrigation/leaching area for a 24-hour period | |
| Coarse sand or gravel | 20 | 5.0 | 0.005 | 203.7 |
| Fine sand | 25 | 4.0 | 0.006 | 162.9 |
| Sandy loam | 40 | 2.5 | 0.010 | 101.8 |
| Sandy clay | 60 | 1.7 | 0.015 | 69.2 |
| Clay with considerable sand or gravel | 90 | 1.1 | 0.022 | 44.8 |
| Clay with small amounts of sand or gravel | 120 | 0.8 | 0.030 | 32.6 |
9 of 10 Certificate of Compliance with Final Express Terms Filed with the Secretary of State on January 27, 2010 (2007 CPC, Title 24, Part 5, Chapter 16A, Part I – Nonpotable Water Reuse Systems)
Table 16A-3 Subsurface Drip Design Criteria of Six Typical Soils
| Type of Soil | Maximum emitter discharge (gal/day) | Minimum number of emitters per gpd of graywater production |
|---|---|---|
| 1.Sand | 1.8 | 0.6 |
| 2.Sandy loam | 1.4 | 0.7 |
| 3.Loam | 1.2 | 0.9 |
| 4.Clay loam | 0.9 | 1.1 |
| 5.Silty clay | 0.6 | 1.6 |
| 6.Clay | 0.5 | 2.0 |
Use the daily graywater flow calculated in Section 1606A.0 to determine the number
of emitters per line.
Graywater shall not be allowed for indoor use, such as flushing toilets and urinals, unless treated by an onsite water treatment system approved by the Enforcing Agency. For the purposes of this section, graywater treated by an on-site water treatment system shall be considered “Treated Graywater”. Treated graywater and treated graywater systems shall comply with the provisions of this code except as otherwise provided in this chapter and all of the following:
NOTE:
Authority Cited: Health and Safety Code Sections 17040, 17921, 17922 and 19990.
Reference: Health and Safety Code Sections 17922.12 and 18941.7.
Excerpted from the full text, below. Systems that meet these standards do not require a permit or inspection.
1603A.1.1 Clothes Washer System. A clothes washer system in compliance with all of the following is exempt from the construction permit specified in Section 108.4.1 and may be installed or altered without a construction permit:
How to Resources:
The new California standard is the culmination of an extensive stakeholder review process with extensive input from building officials, health officials, inspectors, industry and environmental representatives.
Some local jurisdictions are considering altering the new California greywater code in ways that are likely to have the opposite of the effect desired.
Before altering the standard, it would be wise to:
A point of much discussion is the question of whether the most basic class of systems should be
In an effort to maintain control, California attempted "3" the past 20 years. However, Californians do not want to pay $100 for a permit for a system that has less than $100 in parts.
The unintended consequence was to drive greywater reuse completely outside of reach of the potential positive influence of government agencies, building inspectors, licensed professionals, or experienced installers. Virtually all the state's 1.7 million greywater systems are homeowner-built systems that feature uncontained surface application of greywater.
This giant experiment —
There is very little traction for greywater regulation. The best approach is with a light hand, focusing on:
The current standards take this approach, by requiring no permit for the most basic systems, and providing for increasing oversight of increasingly complex or worrisome systems.
For more details and supporting facts and figures on the above, please read these two documents:
Full text of Art Ludwig's testimony to the BSC
Handout to BSC (PDF) includes reasons to have standards but not require a permit for simple systems
Notification/ registration of greywater systems (or a certificate of negative declaration) have been proposed as a possible compromise between permitting and not permitting. The current standard allows this option:
If required, notification has been provided to the Enforcing Agency regarding the proposed location and installation of a graywater irrigation or disposal system.
At first I was excited about this, but then I realized that this would probably be less satisfactory than either of the other scenarios.
I assume that these are the goals of registration:
Registration is likely to have the opposite of the desired effect for every one of these goals. Here's why:
If your jurisdiction is interested in registration, here's an approach that, while it aims a bit lower, I think will actually hit the targets: (I've written it here in the form of suggested language for the state standard, it certainly would be allowed under the current language quoted above)
At the Enforcing Agency’s discretion, the Enforcing Agency may inspect clothes washer and/or single fixture systems concurrent with an inspection on the property for another purpose, an enforcement action for another purpose, or an otherwise required inspection on sale of a property.
Here's the details:
So ...I think this gives the best of both worlds:
If your jurisdiction is interested in going this route, please E mail us; I'd be interested in helping develop optimal language.
Art Ludwig
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