San Francisco Graywater Design Manual

The San Francisco Graywater Design Manual is a detailed practitioner-oriented guide for designing, constructing, permitting, and operating graywater systems used for outdoor irrigation. It is especially useful because it does not limit itself to one narrow system type; instead, it covers laundry-to-landscape systems and also provides an overview of branched-drain and pumped systems. That breadth makes it a strong reference for homeowners, designers, and contractors who need to decide which graywater approach best fits a site and how to document that choice for a permit review.

The manual includes multiple design and sizing steps that are directly actionable. It explains how to estimate graywater flows, calculate irrigation supply, determine soil absorption and distribution area, and perform tests such as the soil ribbon test, laboratory test, and drainage test. These are the kinds of steps that turn a greywater concept into a buildable and permit-ready project. Rather than treating system sizing as an approximation, the manual offers a framework for matching water supply to landscape demand and soil conditions, which helps prevent oversizing, standing water, or poor distribution.

Another useful feature is its guidance on deciding which system type to choose. Readers are instructed to review the types of graywater systems and select the one that best fits their project, then prepare a sketch of the proposed system. If a permit is required, the sketch and supporting details must be submitted to the appropriate permitting office. This makes the manual valuable for navigating administrative requirements as well as technical design. It also references California Plumbing Code guidelines and notes that the system should follow 13 specific guidelines in the code, which gives users a clear compliance framework.

The manual is practical because it blends engineering, code awareness, and real project workflow. It is not just about how graywater works in theory; it is about how to evaluate a property, choose a system, calculate needed capacity, and prepare the application materials required for approval. For practitioners working in regulated environments, this combination of technical and procedural instruction is often what determines whether a project moves forward. The guide therefore offers concrete, site-specific design help and a realistic path from concept to implementation.