Build two infrastructure files before ordering tests
An Occidental home’s water source and wastewater route need separate proof. A property can have a public water account without a public sewer connection, and a sewer bill does not establish the drinking-water source. Begin with the actual parcel and the seller’s service records, then choose inspections that answer specific questions. This prevents a general home inspection or an old permit from being asked to establish a supply, capacity or maintenance conclusion outside its scope.
The Occidental guide describes the local setting, while the Sonoma County guide supplies wider context. This article develops a local evidence packet for the purchase process. Public records checked on October 26, 2026 provide examples of what can be demonstrated. No private system was inspected, no laboratory result was supplied, and no named property is certified here as suitable for a buyer’s planned use.
On public water, identify the account and current conditions
The Occidental Community Services District is the local water-and-fire organization, distinct from the Occidental County Sanitation District. A January 2026 Camp Meeker board packet records coordination over shared water facilities. These sources identify an actual institutional relationship. They do not identify which meter supplies a particular house, its retail charge, or an available allocation for a second unit. District identity; board packet.
Ask for recent bills showing the account and meter, then trace the service to the house and any other buildings with the provider and a qualified inspector. Clarify whether a detached space has an independent account or shares a service. Obtain the current applicable rate schedule directly from the provider; another district’s tariff, a historical capital assessment or a similarly abbreviated agency name is an unreliable substitute for the house’s actual billing arrangement.
Keep system reporting and private plumbing questions separate. The latest applicable water-quality report and current provider notices concern the identified public system. An inspection of pressure equipment, private distribution pipes or a treatment device concerns the house. If a seller has installed filtration, ask what it treats, who services it and which observations support continued use. Neither attractive equipment nor an old service invoice establishes the condition of the complete installation.
A western Coleman Valley case shows the limits of old records
APN 101-090-015 is an actual large Coleman Valley parcel with several historical addresses and scopes. Its WEL20-0505 entry identifies a 12-hour certified yield test and an Approved status dated November 19, 2021. That establishes a test record worth retrieving. The online summary does not disclose a usable yield result here, and a 2021 approval cannot establish October 2026 performance. Do not infer gallons per minute from the duration in the description. Well-test record.
The next request should seek the actual report, its tested source, method, operating conditions and relationship to the buildings under consideration. A qualified well specialist can then identify what current testing and equipment review are appropriate. Include storage, pump controls, treatment, electrical supply and any shared-source documents in the scope. The question is whether the documented installation supports the intended use under relevant conditions, rather than whether an old permit contains the word Approved.
Water-quality sampling is a separate task from yield testing. Ask the specialist and laboratory to identify a suitable sampling plan, the correct point in the system and any treatment affecting results. Preserve the complete report and its collection date. A seller’s recollection of clear water or a pump’s nameplate cannot replace those documents. Likewise, a successful short demonstration during a showing does not describe seasonal supply or the behavior of all equipment under normal demand.
If several buildings draw from the same source, make the demand description explicit before testing or requesting agency direction. An existing residence, occasional workshop sink, irrigated area and proposed additional dwelling create different questions. Do not ask a specialist to approve a vague future lifestyle. Supply a building schedule and actual proposed uses, then keep the specialist’s assumptions with the resulting report so the conclusion can be understood later.
Read septic history without turning ambiguity into a diagnosis
The same western parcel’s history includes a finaled 1996 septic installation and an associated operational-permit entry with an unresolved system-classification question in its description. Those historical entries are reasons to obtain both files. They do not establish a present failure or prove a current treatment category. Some older records use a Bodega Bay locality; reconcile the parcel and system location before attaching them to the current Occidental addresses. Historical system records.
Request the approved design, as-built location, installation and repair documents, operating history and current service records. Have the appropriate specialist identify the tank, treatment components, dispersal area and any replacement area using the actual file and site. Compare the documented design with the existing residence and the buyer’s intended use. An assessor’s room count, visible plumbing or an old clearance for a different building cannot establish wastewater capacity for an addition.
Sonoma’s current regulatory context matters when interpreting older approvals. The North Coast Water Board lists the County’s Local Agency Management Plan as approved on June 16, 2026. Ask Permit Sonoma which present requirements apply to the actual parcel and project. The approval does not extend a decades-old system or justify applying an obsolete manual’s numerical standards to a new proposal. Current regional program information.
For systems with supplemental treatment, the County’s operational-permit program provides an additional file and monitoring route. Ask staff to establish whether the actual installation participates and which current records belong in the purchase packet. The historical OPR label in this case cannot resolve classification by itself. Missing monitoring reports should generate a specific records request, rather than an unsupported statement that every Occidental septic system has identical annual obligations. Operational-permit program.
Physical inspection should be planned around the documented components and safe access to them. Agree in advance what the specialist will inspect, what preparation is needed and which inaccessible areas will remain outside the findings. Keep a location sketch with the report. If the buyer intends to build a driveway, deck or outbuilding, show that footprint to the system reviewer rather than assuming apparently open ground has no wastewater function.
| File branch | Local record lead | Evidence to add before deciding |
|---|---|---|
| Public water | Community Services District; shared regional facilities | Actual meter/account, current tariff and provider conditions |
| Private water | WEL20-0505 demonstrates a dated test record | Underlying result, actual source, current testing and equipment review |
| Septic | Western Coleman Valley installation and OPR history | Reconciled main/operating files and specialist evaluation |
| Public sewer | SEW01-0318 sewer reroute through easement | Actual connection, route instrument, private lateral inspection |
| Proposed change | County requirements and provider review | Written scope-specific capacity/approval direction |
Primary sources: water district, western parcel history, sewer record and regional program. Examples are public-record research, not inspected private cases.
On sewer, inspect the private part as well
The finaled SEW01-0318 record at 14952 Coleman Valley Road describes a sewer reroute through an easement. It illustrates a different investigation from the western septic file: locate the approved route, reconcile associated parcels and retrieve the actual access instrument. Ask who can reach the lateral for maintenance and where private responsibility ends. A historical approval cannot establish present pipe condition or rights for future excavation.
Sonoma Water explains that owners normally maintain and repair private laterals. A qualified camera inspection can help define the actual line’s condition and the limits of what was viewed. The agency’s separate Sonoma Valley ordinance section should not be imported into Occidental as an automatic point-of-sale rule. Describe the inspection being obtained and its findings, with location and date, instead of claiming a mandatory program without confirming applicability. Private lateral guidance.
Public treatment arrangements are another distinct layer. Sonoma Water describes hauling Occidental wastewater to Airport/Larkfield/Wikiup while pursuing a Graton pipeline project. That project does not repair a private lateral or certify capacity for a new dwelling. Ask the sanitation provider to review any proposed increased use, independently of the water inquiry. Keep correspondence with both agencies even when the designer intends to coordinate applications. Wastewater project.
Close the packet with answers tied to the intended home
Organize the completed packet by question rather than by the order documents arrived. Each conclusion should identify the source, date, property component and reviewer. Record exclusions as concrete gaps: an untested well, an unread easement, an inaccessible dispersal area or a proposed use awaiting agency direction. The finished file should allow a buyer to understand what supports the existing residence and what still requires a decision before committing to changes.
