Yuba County Municipal Code Art. 2 Outdoor Use of Graywater

(a) Except as otherwise provided for in this Chapter, the provisions of this Code shall be applicable to gray water system installation. The provisions of this part shall apply to the construction, alteration, discharge, use, and repair of graywater systems. The graywater system shall not be connected to any potable water system without an air gap or other physical device which prevents backflow and shall not cause the ponding or runoff of graywater.

(b) Installation of a gray water system shall not be considered to decrease the capacity of any private sewage disposal system, including any required future replacement areas.

(c) The type of system shall be determined by the location, discharge capacity, soil type, and ground water level. The system shall be designed to handle graywater discharged from the building and may include tank(s) and other appurtenances necessary to ensure proper function of the system.

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 7.09.130 (E).

(d) 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 setback distances indicated in Table 7.09-1.

(e) Fill soil shall not be used to meet the requirements for disposal of graywater.

(f) A standard septic system or pressure dosed septic system that does not have an outlet filter on the septic tank will be required to add one when a gray water system is used. This is to protect the septic system from the high solids waste that may be generated by removing gray water from the septic system influent.

(g) No construction permit for any graywater system shall be issued until a plot plan with appropriate data (as outlined in section 7.09.070) that is satisfactory to the Enforcement Agency (YCEH) has been submitted and approved. When there is insufficient lot area or when soil conditions are not appropriate to prevent the ponding or runoff of the graywater, as determined by the Enforcement Agency (YCEH), no graywater system shall be allowed.

Exception: A construction permit shall not be required for a clothes washer system which does not require cutting into or adding to the existing plumbing system provided that it is in compliance with Section 7.09.061.

(h) All graywater systems shall be designed to allow the user to direct the flow to either the irrigation/disposal field or to the building sewer. The means of changing the direction of the graywater shall be clearly labeled and readily accessible to the user.

(i) Water used to wash diapers or similarly soiled or infectious garments or other prohibited contents such as hazardous chemicals derived from activities including the cleaning of car parts, washing greasy or oily rags, or disposing of waste solutions from home photo labs or similar hobbyist or home occupational activities, shall be diverted by the user to the building sewer.

(j) Graywater shall not be used in spray irrigation, allowed to pond or runoff and shall not be discharged directly into or reach any stormwater system or any surface body of water.

(k) Human contact with graywater or the soil irrigated by graywater shall be minimized and avoided, except as required to maintain the graywater system. The discharge point of any graywater irrigation or disposal field shall be covered by at least (2) inches (51 mm) of mulch, rock, or soil, or a solid shield to minimize the possibility of human contact.

(l) Graywater shall not be used to irrigate root crops or edible parts of food crops that touch the soil.

(m) Common times you are required to divert your graywater system to the building sewer:

(1) During the rainy season.

(2) When washing dirty diapers.

(3) When washing anything with chemicals, such as oily rags.

(4) Anytime you notice that the water isn't draining well and pooling or runoff may occur in the disposal/use area.

(5) If you think your plants are receiving too much water.

(6) Anytime you use products that are harmful to plants (i.e. bleach, harsh cleaners, etc.).

(Ord. No. 1536)

A written construction permit shall be obtained from the Enforcement Agency (YCEH) prior to the erection, construction, reconstruction, installation, relocation or alteration of any graywater system that requires a permit as outlined in the following chart:

Construction Permit Requirements

(Ord. No. 1536)

A clothes washer system in compliance with all of the following is exempt from the construction permit specified in Section 7.09.050 and may be installed or altered without a construction permit:

(1) Notification has been provided to the Enforcement Agency (YCEH) and to any Water Agency that may supply the parcel with domestic potable water. This notification must have plans showing the proposed location and installation of the graywater irrigation or disposal system as well as a completed notification form and the appropriate review fee.

(2) The design shall allow the user to direct the flow to the irrigation/ disposal field or to the building sewer. The directional control of the graywater system shall be clearly labeled and readily accessible to the user.

(3) The installation, change, alteration or repair of the system does not include a potable water connection or a pump and does not affect other building, plumbing, electrical or mechanical components including structural features, egress, fire-life safety, sanitation, potable water supply piping or accessibility.

Note: The pump in a clothes washer shall not be considered part of the graywater system.

(4) The graywater shall be contained on the parcel/site where it is generated.

(5) Graywater shall be directed to and contained within an irrigation or disposal field.

(6) Ponding or runoff is prohibited and shall be considered a potential health hazard and a nuisance.

(7) Graywater may be released above the ground surface provided at least two (2) inches (51 mm) of mulch, rock, or soil, or a solid shield covers the release point. Other methods which provide equivalent separation are also acceptable.

(8) Graywater systems shall be designed to minimize contact with humans and domestic pets. (Shallow and above ground systems must be fenced from all animal intrusion).

(9) Water used to wash diapers or similarly soiled or infectious garments shall not be used and shall be diverted to the building sewer.

(10) Graywater shall not contain hazardous chemicals derived from activities such as cleaning car parts, washing greasy or oily rags, or disposing of waste solutions from home photo labs or similar hobbyist or home occupational activities.

(11) Exemption from the construction permit requirements of this Code shall not be deemed to grant authorization for any graywater system to be installed in a manner that will violate other provisions of this Code or any other laws or ordinances of Yuba County or the State of California.

(12) An operation and maintenance manual for the system shall be provided for the system. Directions shall indicate the manual is to remain with the building throughout the life of the system and indicate that upon change of ownership or occupancy, the new owner or tenant shall be notified that the structure contains a graywater system.

(Ord. No. 1536)

Simple systems discharge more than just graywater from a clothes washer and shall comply with the following:

(1) The discharge capacity of a graywater system shall be determined by Section 7.09.100. Simple systems have a discharge capacity of 250 gallons (947 L) or less per day.

(2) Simple systems shall require a construction permit from the Enforcement Agency. The Enforcement Agency (YCEH) shall consult with any public water system (as defined in Health and Safety Code, § 116275) providing drinking water to the dwelling before issuing a construction permit.

(3) The design of simple systems shall be acceptable to the Enforcing Agency and shall meet generally accepted graywater system design criteria.

(4) Any system requiring modification to the plumbing system, electrical system or other building related appurtenances shall also require the appropriate building permits.

(Ord. No. 1536)

Any graywater system that is not a clothes washer system or simple system shall comply with the following:

(1) The discharge capacity of a graywater system shall be determined by Section 7.09.100. Complex systems have a discharge capacity over 250 gallons (947 L) per day.

(2) Complex systems shall require a construction permit from the Enforcement Agency (YCEH). The Enforcement Agency (YCEH) shall consult with any public water system (as defined in Health and Safety Code, § 116275) providing drinking water to the dwelling before issuing a construction permit.

(3) A complex system shall be designed by a person who can demonstrate competence to the satisfaction of the Enforcing Agency (YCEH).

(4) Any system requiring modification to the plumbing system, electrical system or other building related appurtenances shall also require the appropriate building permits.

(Ord. No. 1536)

Graywater systems for which a construction permit is required must submit plans and details of the proposed graywater system necessary to ensure compliance with the requirements of this Chapter. The Enforcement Agency (YCEH) may require any or all of the following information to be included with or in the plot plan before a permit is issued for a graywater system:

(1) A plot plan to scale completely dimensioned, showing lot lines and structures, direction and approximate slope of surface, location of all present or proposed retaining walls, drainage channels, water supply lines, wells, paved areas and structures on the plot, number of bedrooms and plumbing fixtures in each structure, location of private sewage disposal system and 100 percent expansion area or building sewer connecting to public sewer, and location of the proposed graywater system.

(2) Details of construction necessary to ensure compliance with the requirements of this Ordinance together with a full description of the complete installation, including installation methods, construction and materials as required by the Enforcement Agency (YCEH).

(3) A log of soil formations and ground water level determined by test holes dug in close proximity to any proposed irrigation area, together with a statement of water absorption characteristics of the soil at the proposed site. In lieu of perk tests the Enforcement Agency may allow the use of table 7.09-2, an infiltration rate designated by the Enforcement Agency, or an infiltration rate determined by a test approved by the Enforcement Agency (YCEH).

Exception: The Enforcement Agency (YCEH) may waive the requirement for identification of groundwater level and/or soil absorption qualities based on knowledge of local conditions.

(Ord. No. 1536)

Verification of ground water levels which exceed three 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 or signs of groundwater in a test hole three 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.

(Ord. No. 1536)

(a) Inspection. A graywater system for which a construction permit is required shall be subject to inspection by the Enforcement Agency (YCEH) 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 to the owner and/or tenant. Directions shall indicate the manual is to remain with the building throughout the life of the system and upon change of ownership or occupancy, the new owner or tenant shall be notified the structure contains a graywater system.

(b) Testing.

(1) Tanks shall be filled with water to the overflow line prior to and during inspection. Seams and joints shall be left exposed, and the tank shall remain watertight.

(2) A flow test shall be performed through the system to the point of graywater irrigation or disposal. Lines and components shall be watertight.

(Ord. No. 1536)

(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:

(1) The number of occupants of each dwelling unit shall be calculated as follows:

First Bedroom .....2 occupants

Each additional bedroom .....1 occupant

(2) The estimated graywater flows of each occupant shall be calculated as follows:

Showers, bathtubs .....25 GPD (95 LPD)/occupant and wash basins.

Laundry .....15 GPD (57 LPD)/occupant

The total number of dwellings 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 Enforcement Agency (YCEH).

(Ord. No. 1536)

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 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 Enforcement Agency (YCEH).

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.

(Ord. No. 1536)

(a) Wherever practicable, irrigation or disposal field size shall be computed from Table 7.09-2.

(b) In order to determine the absorption quantities of questionable soils other than those listed in Table 7.09-2, the proposed site may be subjected to percolation tests acceptable to the Enforcement Agency (YCEH).

Exception: Irrigation fields in compliance with Section 7.09.170, 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 Enforcement Agency (YCEH) may waive the requirement for percolation tests based on knowledge of local conditions or may accept other testing methods.

(Ord. No. 1536)

(a) When system design includes a tank, specifications for the tank shall be submitted to the Enforcement Agency (YCEH) for approval. Such plans shall show all dimensions and other pertinent data.

(b) Tanks shall be constructed of solid, durable materials not subject to excessive corrosion or decay and shall be water-tight.

(c) Each tank shall be vented as required by Chapter 9 of the California Plumbing code, shall be sealed against vermin and mosquitoes, and have an access opening to allow for inspection and cleaning.

(d) Each tank shall have its rated capacity permanently marked on the unit. In addition, a sign stating "GRAYWATER IRRIGATION SYSTEM, CAUTION — UNSAFE WATER — DO NOT DRINK" shall be permanently marked on the holding tank.

(e) Each tank shall have an overflow drain. The overflow drain shall have a permanent connection to the building drain or building sewer, upstream of septic tanks, if any. The overflow drain shall not be equipped with a shutoff valve.

(f) The overflow drain shall not be less in size than the inlet pipe. The vent size shall be determined based on the total graywater fixture units as outlined in Table 7-5 of the California Plumbing Code. Unions or equally effective fittings shall be provided for all piping connected to the holding tank.

(g) Each tank shall be structurally designed to withstand all anticipated earth or other loads. Tank covers shall be capable of supporting an earth load of not less than 300 pounds per square foot (1,464.7 kg/m2) when the tank is used for underground installation.

(h) The overflow system must be designed so that the tank overflow will gravity drain to the existing sewer line or septic tank. The tank shall be protected against sewer line backflow by a backwater valve.

(i) An overflow drain and backwater valve is not required on a clothes washer system.

(Ord. No. 1536)

Graywater systems shall comply with Sections 7.09.141 through 7.09.143.

(Ord. No. 1536)

Graywater pipe, valves and fittings shall conform to the requirements of Sections 604.0, 605.0 and 606.0 of the California Plumbing Code.

(Ord. No. 1536)

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 feet (1,524 mm).

(Ord. No. 1536)

All valves shall be accessible and appropriately marked. A backwater valve installed pursuant to this Code shall be provided on all tank drain connections to the sanitary drain or sewer piping.

(Ord. No. 1536)

Irrigation fields, disposal fields and mulch basins used in graywater systems shall comply with this section. Graywater systems may contain either an 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 Enforcement Agency (YCEH).

(Ord. No. 1536)

A mulch basin may be used as an irrigation or disposal field. Mulch basins shall be sized in accordance with Table 7.09.2 and be 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.

(Ord. No. 1536)

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 Enforcement Agency (YCEH), a separate mini-leachfield sized to accept all the backwash and flush discharge water per table 7.09-2. 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.

(2) Emitters shall be designed to resist root intrusion and shall be of a design recommended by the manufacturer for the intended graywater flow and use. For emitter ratings, refer to Irrigation Equipment Performance Report, Drip Emitters and Micro-Sprinklers, Center for Irrigation Technology, California State University, 5730 N. Chestnut Avenue, Fresno, California 93740-0018.

(3) Each irrigation zone shall be designed to include no less than the number of emitters specified in Table 7.09-3, or through a procedure designated by the Enforcement Agency (YCEH). Minimum spacing between emitters is in any direction and shall be sufficient to prevent surfacing or runoff.

(4) The system design shall provide user controls, such as valves, switches, timers and other controllers, as appropriate, to rotate the distribution of graywater between irrigation zones.

(5) All drip irrigation supply lines shall be polyethylene tubing or PVC Class 200 pipe or better and Schedule 40 fittings. All joints shall be properly solvent-cemented, inspected and pressure tested at 40 psi (276 kPa), and shown to be drip tight for five minutes, before burial. All supply piping shall be covered to a minimum depth of two inches (51 mm) of mulch or soil. Drip feeder lines can be poly or flexible PVC tubing and shall be covered to a minimum depth of two inches (51 mm) of mulch or soil.

(6) Where pressure at the discharge side of the pump exceeds 20 psi (138 kPa), a pressure-reducing valve able to maintain downstream pressure no greater than 20 psi (138 kPa) shall be installed downstream from the pump and before any emission device.

(7) Each irrigation zone shall include a flush valve/anti-siphon valve to prevent back siphonage of water and soil.

(Ord. No. 1536)

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:

(1) Disposal systems shall be not less than three inches (80 mm) in cross sectional dimension and shall be constructed of perforated high-density polyethylene pipe, perforated ABS pipe, perforated PVC pipe, leaching chambers or other approved materials, provided that sufficient openings are available for distribution of the graywater into the trench area. Material, construction, and perforation shall be in compliance with the appropriate absorption field's drainage standards and shall be approved by the Enforcement Agency (YCEH).

(2) Filter material, clean stone, gravel, slag, or similar filter material acceptable to the Enforcement Agency (YCEH), varying in size from three-quarter inch (19.1 mm) to two and one-half inches (64 mm) shall be placed in the trench to the depth and grade required by this section. The perforated section shall be laid on the filter material in an approved manner. The perforated section shall then be covered with filter material to the minimum depth required by this section. The Enforcement Agency shall then be called for inspection. After inspection and acceptance filter material shall then be covered with untreated building paper, straw, or similar porous material to prevent closure of voids with earth backfill and then the final earth backfill shall be placed over the filter material cover.

Exception: Manufactured leaching chambers shall be installed in compliance with the manufacturer's installation instructions.

(3) Disposal fields shall be constructed as follows: (See chart below)

(4) 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 the horizontal leaching sections shall be made with approved water-tight joints and installed on natural or unfilled ground.

(Ord. No. 1536)

(a) Other collection and distribution systems shall be permitted by the local Enforcement Agency (YCEH), as allowed by Section 108.7 of the current version of the California Plumbing Code.

(b) Nothing contained in this Chapter shall be construed to prevent a city, county, or city and county or other local government from, after a public hearing and enactment of an ordinance or resolution, further restricting or prohibiting the use of graywater systems. For additional information, see Health and Safety Code § 18941.7.

(c) Graywater stub-out plumbing may be allowed for future connection prior to the installation of irrigation lines and landscaping. Stub-out shall be permanently marked "GRAYWATER STUB-OUT, CAUTION —- UNSAFE WATER-DO NOT DRINK".

Table 7.09-1 Location setbacks for Graywater Systems

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 inches (153 mm) for aboveground tanks when first approved by the Enforcement Agency (YCEH).

3 Where special hazards are involved, the distance required shall be increased as directed by the Enforcement Agency (YCEH).

4 These minimum clear horizontal distances shall also apply between the irrigation or disposal field and the ocean mean higher high tide line.

5 The 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 feet (610 mm) for each additional foot of depth in excess of one foot (305 mm) below the bottom of the gray water drain line.

7 For parallel construction or crossings, approval by the Enforcement Agency (YCEH) shall be required.

Table 7.09-2 Design Criteria of Six Typical Soils

Table 7.09-3 Subsurface Drip Design Criteria of Six Typical Soils

Use the daily graywater flow calculated in Section 7.09.100 to determine the number of emitters per line.

(Ord. No. 1536)