Septic in Sumas, WA

Sumas feels like a tight-knit hillside town where homes sit on generous lots, and the Sumas Prairie breeze carries a sense of open space and practicality. Here, wastewater isn't a one-size-fits-all system—it's about fitting the land you're on and keeping groundwater clean for everyone who shares this corner of Whatcom County.

Is septic common in Sumas? Should I expect septic if I own or buy a home?

Yes. In Sumas, most homes rely on septic systems because many streets aren't served by a centralized sewer, and extending a sewer line to every property isn't always practical or affordable. If you're buying a home here, plan on a septic system being part of the package—and check the current system's status. A real estate transaction usually benefits from a thorough septic inspection and a review of maintenance records, along with any state or local permits. Even when a home is connected to sewer elsewhere in the county, your particular parcel may still be on septic, so it's a good habit to verify.

Why homes typically use septic systems in Sumas

• Rural layout and lot sizes: Many Sumas properties sit on parcels that make extending sewer lines costly and time-consuming. On-site treatment offers a practical, scalable solution.
• Local geology and drainage: Soil type, groundwater depth, and drainage influence how a system is designed and how well it performs, especially with seasonal rains.
• Cost and infrastructure: Building and maintaining a septic system can be more economical for individual homes than extending municipal sewer infrastructure to every property.
• Regulatory realities: When public sewer isn't available, state and local guidelines encourage safe, properly designed on-site systems to protect water quality and nearby wells.

High-level explanation (why septic exists here)

On-site systems are a straightforward way to treat wastewater right where it's generated. They reduce the need for large-scale sewer expansion, support flexible land use, and, when installed and maintained correctly, help protect soils and groundwater in the Sumas area. Think of septic as a practical, neighbor-friendly solution that aligns with the practical spirit of our community.

A friendly note from a neighbor who's also a local septic pro: you'll find straightforward guidance and nearby support here, designed to help you understand, maintain, and plan for a healthy system—and a healthier yard you can enjoy year-round.

Where Septic Systems Are Common in Sumas

Common locations in Sumas

• Rural, unsewered properties on larger lots near the outskirts of town. When public sewer service isn't available, home wastewater typically goes to an on-site septic system.
• Agricultural parcels and farms where on-site drainage and soil absorption are practical for individual systems.
• Older neighborhoods developed before sewer mains were extended or before municipal sewer service reached the area.
• Newer subdivisions or single lots where sewer access is limited or costly, so homeowners rely on well-designed septic systems instead of connecting to a public sewer line.

Why septic systems are common here

• Density and land use: Much of Sumas is low-density, with plenty of space for a septic drainfield and reserve area, making on-site systems a sensible choice.
• Cost and practicality: Extending public sewer to sparsely populated or remote areas is expensive. Septic keeps wastewater disposal local and private for individual properties.
• Soil and groundwater realities: Soils in parts of the Sumas area vary, and well-drained soils support drainfields when designed and installed correctly. In zones with limited drainage or high groundwater, alternative septic designs (such as mound systems) may be used.
• Regulation and safety: Local and state programs regulate septic permits, inspections, and maintenance, helping ensure systems operate safely and protect water quality.

Common system designs you might encounter

• Traditional gravity drainfield with a septic tank. This is the most familiar setup for many homes in the area.
• Raised or mound systems in yards with shallow soil, high water table, or limiting conditions. Mounds provide an elevated drainfield that reaches deeper, better-draining soil layers.
• Alternative designs for challenging sites, such as bed or chamber systems, when space or soil conditions require a different approach.
• Simple, properly sized systems with setback buffers from wells, streams, and property lines—installed and inspected to meet local requirements.

Practical considerations for Sumas homeowners

• Site suitability: Before buying or building, check whether your property has appropriate soil depth, drainage, and space for a drainfield, plus required setbacks from wells, buildings, and water features.
• Permitting and design: Work with a licensed septic designer or contractor to obtain the necessary permits and to design a system suited to your soil and lot. Your local health department can guide you on required steps.
• Maintenance: Regular pumping (as recommended by a qualified professional) and annual inspections help prevent failures and protect groundwater.
• Future changes: If sewer lines ever reach your area, you may have options to connect. Understanding local options now can help you plan.

How to verify your property's septic viability (quick steps)

1. Contact Whatcom County Environmental Health or the state Department of Health to confirm whether public sewer service is available to your address and what your options are if it isn't.
2. Hire a licensed septic designer to evaluate soil texture, percolation rates, and groundwater conditions for your site.
3. Have a complete system design prepared that complies with county and state regulations.
4. Obtain required permits, get the system installed by a licensed contractor, and schedule regular maintenance visits.

Official resources

• Washington State Department of Health – Onsite Sewage Systems:
• Washington State Department of Ecology – Onsite Wastewater:

Septic vs Sewer: What Homeowners in Sumas Should Know

How septic systems and sewer differ in practice

In Sumas, your daily experience hinges on whether your home connects to a municipal sewer system or operates on an on-site septic system. Here's what that means in practical terms.

• Public sewer: Wastewater is collected by a city or district sewer network and sent to a treatment plant. You typically pay a monthly sewer bill, and routine maintenance is handled by the utility. No septic tank or drain field is on your property.
• On-site septic: A buried tank treats solids on your property, with liquid effluent dispersed through a drain field. You're responsible for pumping, inspections, and repairs, and problems can be costly if not caught early.
• Costs and planning: Sewer users face ongoing monthly charges and possible connection fees. Septic owners pay for installation up front, plus periodic pumping, inspections, and potential repairs. Over time, maintenance needs should be part of your budgeting.
• Availability and choice: Some Sumas neighborhoods are served by public sewer; others rely on on-site systems. Confirm your service status with your local utility and appropriate public health offices.

Is a septic system the right choice for your Sumas home?

1. Verify service status with your utility or Whatcom County Public Health to know if you're on sewer or on a septic system.
2. Compare long-term costs: upfront installation for septic versus ongoing sewer bills and any connection fees.
3. Assess site suitability: soil percolation, lot size, groundwater depth, and space for a drain field. WA Ecology's onsite sewage guidelines apply here.
4. Plan for maintenance: set aside funds for periodic pumping (typical range is every 3–5 years, depending on tank size and usage) and occasional inspections.
5. Understand regulations: septic systems in Washington are governed by state and local codes; check permit and inspection requirements before installation or modification.

Pros and cons at a glance

• Septic system
  • Pros: independence from a sewer utility, potential savings if you're in a rural area with reasonable maintenance costs, flexibility in land use.
  • Cons: ongoing maintenance responsibility, risk of costly failures if neglected, potential environmental concerns if not properly managed.
• Public sewer
  • Pros: predictable monthly bills, professional maintenance, no on-site drain field to monitor or repair.
  • Cons: ongoing utility costs, dependence on service availability and sewer infrastructure, potential special charges for capacity or outages.

Maintenance essentials for Sumas homeowners

• Pump on a schedule appropriate for your tank size (commonly every 3–5 years); keep records of pump dates.
• Use water-saving fixtures and avoid flushing non-biodegradable items, grease, or chemical cleaners that can disrupt the system.
• Protect the drain field: avoid heavy equipment, don't plant deep-rooted trees above it, and keep it free from runoff and drainage issues.
• Inspect regularly: look for signs of failure such as gurgling sounds, unusual odors, damp spots, or backing up drains, and contact a licensed pro promptly.
• Stock a small emergency fund for unexpected repairs and maintain access to the tank lid for inspections.

Quick-start steps for Sumas homeowners

1. Locate and map your septic tank and drain field (or confirm sewer service with the utility).
2. Check last pumping date; schedule a pump if due or overdue.
3. Monitor water use and avoid non-septic-safe products.
4. Schedule an annual or semiannual inspection with a licensed septic professional to catch issues early.

Resources

• EPA Septic Systems:
• Whatcom County Public Health (Environmental Health / Septic Programs): https://www.whatcomcounty.us/Health'>https://www.whatcomcounty.us/Health
• Whatcom County Official Site: https://www.whatcomcounty.us

Typical Septic System Types in Sumas

Conventional septic systems (gravity drainfield)

• What it is: A straightforward setup with a septic tank that holds solids and a network of perforated pipes in a gravel bed or chamber drainfield.
• When it fits: Works best where soils drain moderately well and groundwater is not perched too close to the surface.
• Pros: Simple design, generally lower upfront cost, easy maintenance.
• Cons: Requires adequate soil depth and separation from groundwater; performance can decline if the drainfield is flooded or waterlogged.
• Common components: Septic tank, distribution box, perforated pipes, gravel or chamber drainage bed.

Pressure distribution and mound systems

• What it is: A dose-and-distribute approach to spread effluent more evenly, or an engineered mound built above native grade to reach suitable soils.
• When it fits: Needed with long drainfields on sloped sites, poor soils, shallow groundwater, or restricted excavation depth.
• Pros: Improves system reliability in marginal soils; can extend life of a drainfield.
• Cons: More complex and costly to install and service; requires electricity for dosing in most cases.
• Typical features: LPD (low-pressure dose) or siphon dosing, raised mound with a designed soil layer, monitoring ports.

Advanced treatment and alternative drainfields

• What it is: Systems that treat or distribute effluent more aggressively than a conventional drainfield.
• When it fits: On sites with higher wastewater loads, limited space, high groundwater, or soils that don't meet standard drainfield criteria.
• Pros: Higher effluent quality before it reaches the drainfield; can improve longevity of the system in tough soils.
• Cons: Higher upfront and ongoing maintenance costs; usually requires licensed installation and service.
• Common options:
  • Aerobic Treatment Units (ATUs): Protect with electrical power; provide additional treatment before disposal.
  • Sand/soil filters or constructed wetlands: Additional polishing step before discharge.
  • Chamber systems or enhanced evapotranspiration-like layouts: Lightweight, easily installed drainfield alternatives that rely on engineered voids or soil conditions.
  • Drip irrigation or low-pressure dispersal: Targeted effluent application with smaller emitters; used in tight lots or challenging soils.

Holding tanks and seasonal-use systems

• What it is: Tanks that store wastewater rather than disperse it on-site; liquid waste is pumped out periodically.
• When it fits: Seasonal properties, short-term occupancy, or where on-site disposal isn't permitted year-round.
• Pros: Flexible for seasonal homes; avoids placing a drainfield in unsuitable soils.
• Cons: Requires regular pumping and transfer agreements; not a long-term disposal solution for year-round homes in many areas.
• Maintenance note: Regular pumping by a licensed hauler and safe disposal are critical.

Shared or community septic systems

• What it is: A single, larger system serving multiple homes or units, instead of individual onsite systems.
• When it fits: In subdivisions, rural clusters, or properties with limited space for separate drainfields.
• Pros: Can be more space-efficient and easier to monitor and maintain at scale.
• Cons: Requires formal agreements, ongoing maintenance funding, and proper operation to protect water quality.

Steps to consider when choosing a system (quick guide)

1. Obtain soil and site assessments to gauge percolation, depth to groundwater, and structure constraints.
2. Review Whatcom County and Washington state regulations for your property type and location.
3. Consider long-term maintenance costs and the availability of qualified local service providers.
4. Hire licensed professionals for design, installation, and inspection to ensure code compliance and performance.

Official resources

• Whatcom County Health Department – Onsite Sewage Systems:
• Washington State Department of Ecology – Onsite Sewage Systems: Permits/Onsite-Sewage-Systems
• Washington State Department of Health – Onsite Sewage Systems:

Common Septic Issues in Sumas

High groundwater and seasonal water table

• Signs to watch: slow drains, surface sogginess over the drain field, wet spots or spongy ground above the disposal area, sewage odors near the system after rains.
• Why Sumas is unique: Whatcom County's flood-prone areas and proximity to the Nooksack River mean many soils stay saturated in winter. A shallow, perched water table reduces the drain field's ability to absorb effluent, increasing the chance of backups.
• What to do:
  1. Conserve water during wet months (spread out laundry, limit long showers).
  2. Have the septic pumped and inspected if you notice standing water over the field.
  3. Consider a professional assessment for drainage options or an engineered design (e.g., elevated or mound systems) if the site consistently stays wet.
  4. Keep heavy rain off the drain field by grading away from the area and avoiding vehicle or foot traffic on the field.
• Resources: EPA on septic systems, and Washington State Ecology's Onsite Sewage Systems page for design and maintenance guidance (

Soil permeability and drainage challenges

• Signs to watch: frequent backups with normal drainage elsewhere on the property, wet lawn patches that don't dry, and grass that grows unusually well directly over the field (indicating moisture saturation rather than healthy drainage).
• Why Sumas soils can pose problems: glacially deposited soils range from tight clays to variable sands; clay pockets and perched layers hinder percolation, especially after rainfall.
• What to do:
  1. Get a professional soil test or percolation test to determine field capacity.
  2. If percolation is poor, discuss alternatives with a licensed septic designer (e.g., mound systems, pressure-dosed fields, or creative layout to find better-drained sections).
  3. Limit irrigation and landscape watering near the drain field to reduce soil saturation.
• Resources: WA Ecology OSS pages and EPA septic guidance for design considerations (

Well water and groundwater considerations

• Signs to watch: sudden changes in water taste or color, septic odors near wells or in the yard after rainfall.
• Why unique here: some Sumas homes rely on wells in areas where groundwater movement can affect septic performance, especially during wet seasons; contamination and cross-connection risk increases if the system isn't properly isolated from the well.
• What to do:
  1. Test groundwater periodically if you rely on well water and have a septic system nearby.
  2. Maintain proper separation distances between well heads and the septic system per local regulations.
  3. Seek professional advice if you notice changes in water quality or increased odors.
• Resources: EPA groundwater and septic guidance; WA Ecology OSS guidelines for setbacks and separation distances.

Septic Inspection, Permits & Local Oversight

Who Oversees Septic Permits in Sumas

In Sumas (Whatcom County), the local health department generally administers onsite sewage system (OSS) permits, plan reviews, inspections, and record-keeping. If you're within the City of Sumas, confirm whether the city has its own permitting process in addition to the county OSS program. Statewide guidelines and technical standards come from the Washington Department of Ecology, but the day-to-day permitting and inspections are handled locally.

Useful reference: Washington Department of Ecology OSS resources (statewide rules and guidance) at For county services, check Whatcom County Health Department's OSS information on their site.

What Permits Might Be Required

• OSS permit for installation, upgrade, replacement, or expansion of a septic system.
• Building or construction permits if your project involves new construction, additions, or changes that affect the OSS location or performance.
• Trenching, excavation, or other activity permits if required by county or city codes for safety and utility clearance.
• Actions tied to connecting to a public sewer (where applicable) may involve different approvals.

Note: Permits are typically required before starting work. Routine maintenance or minor repairs that do not change the system's design or capacity may not need a new OSS permit, but any substantial modification or replacement will.

Steps to Apply for a Permit

1. Hire a licensed designer or septic installer (if needed) to prepare a plan and site evaluation.
2. Submit the OSS permit application, design, site plan, and supporting documents to the issuing agency (Whatcom County Health Department is the usual point of contact for OSS in unincorporated areas; the City may have its own process if you're inside city limits).
3. Pay applicable review and processing fees; wait for plan review approval or requests for additional information.
4. Schedule installation inspections as work progresses (see next section).
5. Obtain final approval after successful inspections; this typically finalizes the permit.

Helpful preparation:

• A clear lot/site plan with setbacks, soil evaluation reports, and drainfield design
• Property address, legal description, and lot dimensions
• Contact information for your contractor or designer

Inspections: What to Expect

• Pre-installation inspection: verify soil suitability, location, and design conformance before trenching or tank placement.
• In-progress inspections: inspect tank placement, septic tank integrity, piping, distribution box, and trenching work as it proceeds.
• Final inspection: confirm system is installed per plan, functional, and meets setback and connection requirements; obtain final approval or cure items if needed.

Tips:

• Schedule inspections with ample lead time; weather and access can affect timing.
• Have the inspector review notes and plans on-site to minimize rework.

Local Oversight Contacts

• Whatcom County Health Department – Onsite Sewage System (OSS) Program: primary contact for OSS permits, plan reviews, and inspections in most of the county.
• City/Local City Hall (if within Sumas city limits): verify any city-specific septic or building permit requirements.
• Washington Department of Ecology – Onsite Sewage Systems (statewide guidance and regulatory framework):

Quick Reference: Common Scenarios

• New construction with a septic system: OSS permit + building permits; multiple inspections required.
• Replacement of an failed drainfield or tank: OSS permit needed; final inspection required.
• Minor repairs that do not change the system's design: may not require a new OSS permit, but check with the issuing agency.

Official resources:

• Washington Dept. of Ecology – Onsite Sewage Systems: https://ecology.wa.gov/Regulations-Permits/Permits-by-type/Onsite-sewage-systems
• Whatcom County Health Department – OSS information: (search for "Onsite Sewage System" on the Whatcom County Health Department site)

Septic Maintenance for Homes in Sumas

Sumas-specific site considerations

Sumas and the nearby Sumas Prairie sit on soils with relatively high groundwater and can experience seasonal flooding. This combination lowers the soil's treatment capacity and can cause surface-ponding during wet periods. Local health and environmental rules require proper setbacks from wells, streams, and property boundaries, and you'll find these requirements reflected in your system permit and local codes. If your home is in a floodplain or near the Nooksack River, your maintenance and pumping plan may need to be adjusted to account for saturated soils and potential backup conditions.

• High groundwater and saturated soils reduce drainfield efficiency, especially after heavy rains or rapid snowmelt.
• Flood-prone areas require extra caution: drains can back up, and surface water can overload the absorption field.
• Keep distances documented in your permit—setbacks from wells, streams, and other water features matter for long-term reliability.

Routine maintenance schedule

A simple, regular rhythm helps keep a Sumas septic system flowing smoothly, even in challenging soils and weather.

1. Pumping and tank care
2. Most households with gravity systems should plan a pump-out every 2–3 years. Larger families, heavy disposal (garbage disposals, lots of dishwasher/utility sink use), or older systems may need 1–2 year pumping intervals. Newer, well-maintained systems or those with cautious usage can stretch toward 4–5 years.
3. If you have a pump tank or dosing system, include pump inspection and testing as part of the pump-out schedule.
4. Annual professional inspection
5. Have a licensed septic professional inspect the tank, baffles, filters, and any pumps or floats. They should verify the integrity of the SSD (septic) components and ensure there's no standing water, unusual odors, or signs of distress in the drainfield.
6. Ask for records and a written plan tailored to Sumas soil conditions and your property.
7. Recordkeeping
8. Maintain a simple log of pumping dates, inspections, repairs, and any observed symptoms (toilet backup, slow drains, odors). This helps track performance over time and supports local permitting if you ever need to adjust the system.

Protect the drainfield in flood-prone Sumas

Flooding and perched groundwater are common concerns here. Protecting the drainfield improves reliability and water quality.

• Do not drive or park on the drainfield or soil cover above it.
• Avoid planting deep-rooted trees or aggressive shrubs near the absorption area; keep landscaping shallow‑rooted and well away from the field.
• Direct surface water away from the drainfield and consider grading or swales to reduce surface pooling near the bed.
• After heavy rains or flood events, have the system inspected for surface saturation or slowed absorption before heavy reuse.

Water use and landscape practices

Conserve water to reduce load on the system, especially when soils are already saturated.

• Run full loads less often; stagger laundry and irrigation, especially during wet seasons.
• Install low-flow fixtures and fix leaks promptly; every gallon saved helps.
• Avoid putting grease, solvents, paints, or harsh chemicals down the drain. Use septic-safe cleaners and dispose of chemicals through proper channels.
• Choose shallow-rooted, non-invasive ground covers near the drainfield; avoid new trees or shrubs with aggressive rooting nearby.

Seasonal considerations for Sumas

Winters can be damp and springs can bring rapid groundwater rise.

• Before winter, confirm that the pump and control panel are functioning; consider backup power if outages are common.
• After a flood or prolonged wet spell, schedule a quick inspection to confirm the drainfield isn't saturated and that there's no surface backup.

Signs of trouble and immediate steps

Watch for baseline indicators that something is off, especially in flood-prone soils.

• Slow drains, gurgling sounds, sewage odors, or damp, unusually green patches over the drainfield.
• Actions: reduce water use, avoid flushing nonbiodegradables, and contact a licensed septic professional for a diagnostic.

Resources from official agencies

• Washington Department of Health – Onsite Sewage Systems:
• Washington State Department of Ecology – Onsite Sewage Systems:
• EPA – Septic Systems: https://www.epa.gov/septic
• In addition to these national and state resources, check with your local Whatcom County Health Department for county-specific maintenance requirements and permit records, as they administer on-site wastewater programs within Sumas.

Cost Expectations for Septic Services in Sumas

Septic Tank Pumping and Cleaning

• What it includes: removing sludge and scum from the tank, routine inspection of tank condition, lid access check, and a basic assessment of nearby drain lines for signs of trouble.
• Sumas-specific factors: remote service calls, travel charges, and potential winter access issues on hillside properties; clay soils and seasonal groundwater can affect pumping frequency.
• Typical cost in Sumas: $350–$650, depending on tank size (most residential tanks are 1,000–1,500 gallons) and accessibility.
• Before you schedule (steps you can take):
  1. Locate the tank and confirm the lid is accessible.
  2. Note any gates or pets that need handling during service.
  3. Have any recent drain-field signs (wet spots, gurgling) ready to discuss.

Septic System Inspection

• What it includes: visual and mechanical check of the tank, baffles, inlet/outlet pipes, distribution box, and accessible lines; may include camera inspection of lines if issues are suspected; basic performance assessment.
• Sumas-specific factors: many homes use gravity-fed systems; groundwater and soil conditions can impact performance; inspections help catch early field issues before failures.
• Typical cost in Sumas: $250–$750 for a standard inspection; higher if a full system evaluation or camera work is included.
• Before you schedule (steps you can take):
  1. Gather any previous inspection reports.
  2. Make sure access to the tank and drain field is clear.
  3. Plan for potential follow-up recommendations (repairs or field service) if needed.

Drain Field Evaluation and Soil/Leakage Check

• What it includes: surface examination for wet areas, odor, or lush vegetation; soil probe or soil texture assessment; may include infiltration tests or pressure tests; review of field wiring and drainage.
• Sumas-specific factors: heavy clay soils and the area's high seasonal water table can mask or accelerate field issues; early evaluation helps avoid costly replacements.
• Typical cost in Sumas: $500–$2,500, depending on the extent of testing and whether a camera or diagnostic tools are used.
• Before you schedule (steps you can take):
  1. Mark the status of any surface damp spots or odors.
  2. Confirm nearby wells or water usage that might influence tests.
  3. Have the system's most recent pumping and maintenance records handy.

Drain Field Repair or Replacement

• What it includes: repair of damaged distribution box, damaged pipes, trench restoration, or full drain-field replacement if failure is confirmed.
• Sumas-specific factors: clay soils, high water table, and winter weather can complicate field work and extend timelines.
• Typical cost in Sumas: repair $2,500–$15,000; full replacement $10,000–$40,000 depending on field size, access, and materials (mounds or trenches may alter price).
• Before you schedule (steps you can take):
  1. Obtain a written assessment from the inspector.
  2. Get multiple quotes, especially if a full replacement becomes likely.
  3. Plan for potential site work and perennial access restrictions.

New Septic System Installation (Design, Permits, and Build)

• What it includes: site evaluation, system design, soil analysis, permit processing, gravel/trench work, tank installation, and field installation.
• Sumas-specific factors: hillside lots, poor soils requiring mound systems, and remote locations can add design complexity and cost; permitting with Whatcom County is a key step.
• Typical cost in Sumas: $10,000–$40,000+ depending on system type (gravity, mound, aerobic), lot constraints, and access.
• Before you schedule (steps you can take):
  1. Obtain a preliminary site plan and lot topo if available.
  2. Discuss potential system types early (gravity vs. mound vs. aerobic).
  3. Budget for permit fees and potential site preparation costs.

Septic Tank Risers, Lids, and Filter Upgrades

• What it includes: adding or upgrading risers for easier maintenance access, installing or upgrading effluent filters, and improving system monitoring.
• Sumas-specific factors: easier future maintenance reduces service calls in remote properties; weather and ground freeze conditions can affect lid accessibility.
• Typical cost in Sumas: $1,000–$3,000 depending on materials and the extent of the upgrade.
• Before you schedule (steps you can take):
  1. Identify current tank depth and access points.
  2. Choose durable lids and compliant risers.
  3. Schedule during milder weather if possible to minimize disruption.

Permitting, Design, and Administrative Work

• What it includes: plan review, engineering design (if required), and permit processing with local health or planning departments.
• Sumas-specific factors: Whatcom County may require specific approvals for new installs or large repairs; coordination with utilities can be part of the process.
• Typical cost in Sumas: $1,000–$6,000 depending on project scope and design needs.
• Before you schedule (steps you can take):
  1. Confirm required permits early with the local health department.
  2. Gather property drawings and any previous system reports.
  3. Allow extra time for permit approvals in spring and summer.

Official resources

• Washington State Department of Health – Septic Systems:
• Washington State Department of Ecology – On-site Sewage Systems: https:// ecology.wa.gov/Water-Shorelines/Water-quality/Solid-waste-sewage/On-site-Sewage-Systems