Webinar: Understanding the California Plumbing Code for Greywater (Gray water) Installations

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Cory Hensley
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1 Presentation: Laura Allen March 30 th, 2016 Webinar: Understanding the California Plumbing Code for Greywater (Gray water) Installations

2 Overview of Presentation 1) Greywater code basics 2) Who enforces the code? Who can pull a permit? 3) Key concerns with greywater addressed in code 4) Code at a glance 5) Getting a permit- the range of potential experiences

3 Greywater Code Basics California Plumbing Code (CPC) is created from IAPMO's model Uniform Plumbing Code (UPC) with modifications by HCD based on stakeholder input Triennial code adoption cycle Department of Housing and Community Development (HCD) writes code and proposes it to the Building Standards Commission (BSC), who adopts and approves it Input of greywater practitioners needed!

4 Greywater in California Plumbing Code (CA Code of Regulations, Title 24, Part 5) History Pre Appendix J, then G (DWR) Graywater Systems 2009 (2007 CPC)- Chapter 16A: Nonpotable Water Reuse Systems Chapter 16: Alternate Water Sources for NonPotable Applications Chapter 15: Alternate Water Sources for NonPotable Applications

5 Upcoming 2016 Code Published before July 1 st, 2016 Goes into effect January 1 st, 2017 View it here: s/docs/2016cpc_et-final.pdf

6 Does Your Town/County Use This Code? Find out what version of CPC is adopted (not all areas are up to date) Find out if there are any ordinances about greywater (either an old ordinance, or a new one) Is the dwelling covered by this code?

7 HCD 1: Dwellings, condos, hotels, apartments, and more HCD 2: Permanent and accessory buildings in mobile home parks The Adoption Matrix

8 Who Enforces the Code? Authority Having Jurisdiction Enforcing Agency This is open to local interpretation and precedent: Typically: Building Department (plumbing permit) County Environmental Health Department (especially if the site is not in city limits) County Public Health Department

9 Who Can Pull a Permit? Complying with CA Contract Law: 1) For any job costing over $500 installer must be licensed Or Plumbing contractor General contractor (if job includes 3 trades) Landscape contractor General engineering contractor Class A 2) Owner-builder (the home owner)

10 Be prepared to upgrade plumbing if you get a permit.

11 Code Addressed Key Concerns 1. Protective of human health: Prevents human contact, pooling, vectors, hazardous inputs, and cross-contamination of potable supply 2. Protective of environment: Prevents runoff, contains setbacks from well, waterways, etc. and prevents hazardous inputs

treatment requirements for subsurface/subsoil irrigation or disposal

12 Untreated vs. Treated Greywater Minimum Water Quality Requirements No water treatment requirements for subsurface/subsoil irrigation or disposal field On-site treated graywater systems: local public health AHJ creates water quality requirements or NSF 350 shall apply Nexus EWater

13 NSF 350 Certification manufactured systems regarding water quality: Indoor reuse, surface or subsurface irrigation Residential and commercial systems Test for BOD, TSS, turbidity, ph, E. coli,

14 Basic Requirements 1) Designed with a diverter valve 2) No poopy diapers (or other similarly soiled garments), no hazardous chemicals 3) No spray irrigation, no ponding, no pooling, no runoff 4) Outlet has a 2 inch cover (preventing contact) 5) Owner must have operation and maintenance manual 6) Greywater system shall not be connected to any potable water system without adequate protection (e.g. air gap, RP, etc.) 14

15 Tiers of Greywater Systems 1. Washing machine system Doesn't alter drainage plumbing Follows 12 guidelines No permit required 2. Simple system Under 250 gallons/day All fixtures Needs permit, unless excepted by Enforcing Agency 3. Complex system Over 250 gallons/day, needs permit Between 8/04/09 and 1/27/10- "Single fixture" systems were allowed with no permit under the same requirements as a 15 washing machine system

16 Protect Groundwater Greywater can not discharge into ground water without a minimum 3 foot separation of soil. With seasonally high ground water greywater must be diverted into sewer/septic For questionable locations a 3 ft. test hole can be used (if there is no water in it then the water table is far enough away) 16

17 Code Compliance to Prevent Pooling and Runoff 17

18 Calculations Using the Code 1) How much greywater will be generated? 2) What is the soil type? 3) How large of an infiltration area is required? 18 Image Ty Teissere

19 Procedures for Estimating Based on either 1. Water use records 2. Calculations of local daily per person interior use 3. Code procedure Discharge Note: Untreated greywater must be discharged daily (no storage over 24 hours). Treated greywater can be stored. 19

20 CPC Calculations for Discharge 1. Number of occupants 1st bedroom = 2 people Additional bedrooms = 1 person 2. Estimated greywater Showers, baths, washbasins= 25 GPD per person Laundry= 15 GPD per person 3. Multiply people by estimated discharge 20

21 Using the Code 1. How much laundry greywater is produced from 2 people in a 3 bedroom house? 3 bed = 4 occupants x 15 GPD = 60 GPD 2. From the shower of 1 person living in a 4 bedroom house? 4 bed = 5 occupants x 25 GPD = 125 GPD *Use this calculation to size the basins, regardless of the actual amount of greywater generated in the house. 21

22 How large a basin do you need to soak up the estimated greywater? Code language: Required Area of Subsurface Irrigation Fields, Subsoil Irrigation Fields and Mulch Basins. 22

Determination of Max. Absorption Capacity (A) Use Table 1602.10 Need to know soil type Types of acceptable soil tests are:?

23 Determination of Max. Absorption Capacity (A) Use Table Need to know soil type Types of acceptable soil tests are:??? Some cities will give a choice of using a soil test, or choosing a slow draining soil type (B) For soils not listed in Table use percolation test or other method acceptable to AHJ Official percolation tests cost thousands of dollars (C) If percolation test shows soil won't absorb greywater, system can't be built. 23

24 Table Design of Six Typical Soils To calculate square feet GPD/ soil type #= Square feet 100 gallons in fine sand= 100/4.0 = 25 square feet 24

25 Determine Soil Type Field Test Laboratory Test (~$30) 25

26 Minimum Irrigation Field The cumulative square footage of the mulch basins must be at least as big as the minimum irrigation field requirements. (It is typically very easy to meet this minimum requirement.) 26 Image Ty Teissere

27 Image Nicholas Holmes 27 Image Nicholas Holmes

28 Note: How many plants you decide to irrigate depends on actual greywater production, not code estimate 28

29 Setbacks 29

30 Getting a Permit: What to Expect Best case scenario: No permit required for simple systems (with specific guidelines). Example: Santa Barbara County Good scenario: Standard plan, one permit, installer conducts soil test or uses lab. Examples Oakland, Los Angeles. Not so good: Two permits or more (plumbing permit plus environmental health permit, plus other) Worst case: Double or triple permit, on-site soil test from soil engineer (certified percolation test). 30

31 Specification Sheet Credit: Second Generation Water 31

32 32

33 Example of permit requirements: Site Plan Credit: Leigh Jerrard 33

34 Show set backs: from property line (1.5 ft) and house (2 ft.) (When applicable include setbacks from wells, septic, creeks, etc.) Show dimensions and area of irrigation field (mulch basins) must total minimum size based on soil type and gallons per day of greywater generated. Irrigation plot plan not to scale, but shows building footprint, property lines, greywater line, and irrigation area. Permitted system in Oakland

35 35

36 Site Plan (part 1) Credit: Second Generation Water 36

37 Credit: Second Generation Water 37

38 Hand-Drawn Site Plan Example 38

39 Credit: Christina Bertea

40 Example of permit requirements: Irrigation Field Detail Credit: Leigh Jerrard 40

41 41

42 Riser Diagram 42

43 Credit: Second Generation Water 43

44 Example of permit requirements: Riser Diagram 44

45 Example of permit requirements: Plumbing Details Credit: Christina Bertea 45

46 Example of permit requirements: Riser Diagram Pumped System 46

47 Cut Sheet- Flow Splitter 47

48 Cut Sheet: Backwater Valve 48

49 Cut Sheet: Diverter Valve 49

50 Label all pipe (LA only) Clean-out requirement 50 Image Leigh Jerrard

51 Old steel 1.5 shower drain GREYWATER SEWER Permitted system in Oakland

Joints and bends left unburied for inspection 1 st split 2 fitting,

52 Greywater pipe exits through existing vent. Screen resealed to prevent animal entry. Joints and bends left unburied for inspection 1 st split 2 fitting, reduces to 1 ½ for rest of system Clean-out. Exposed pipe will be painted to protect from sun Permitted system in Oakland

53 Recommendations 1) Local jurisdiction exempt simple, lowest-risk systems from permit (e.g. single family homes, gravity flow, no pumps, no storage, system. 2) Cities and counties create standard plans for both gravity flow systems (no tanks, no pumps) and pumped systems. 3) Local jurisdiction requires only 1 permit, the other AHJ can waive permit requirement.

54 Thank you! Questions?

GRAYWATER SYSTEMS FOR RESIDENTIAL BUILDINGS

City of Azusa Building & Safety Department 213 E. Foothill Blvd. Azusa, CA 91702-1395 (626) 812-5234 Fax: (626) 334-5464 GRAYWATER SYSTEMS FOR RESIDENTIAL BUILDINGS A. GRAYWATER SYSTEMS Under State regulations,