2026 OWTS Program Updates

• Change of Use Review
• Previously: Policy
• Updated: Required when proposing a change or expansion of OWTS use (e.g., bedroom addition, commercial use change).
  • System verification required.
  • System must be functioning as intended.
  • Soil testing may be required unless a compliant test is on file.
  • Engineer letter required for engineered systems, evaluating design parameters under current regulations.

• Residual Head Test (Squirt Height)

• • Previously: Policy under Operation and Maintenance
  • Updated: Testing required for all zones and must be documented in the engineer’s certification letter.

• OWTS Certified Inspection Review

• • Previously: Required at property sale
  • Updated: Property sale inspection requirement removed.
    • EPCPH retains certified inspection standards, now offered as voluntary.
    • Issued document renamed Notice of Determination.
    • Certified inspections still required for:
      • Change of Use requests
      • Cesspool remediation requests
      • At the discretion of EPCPH for other reasons as necessary

• Licensing of System Contractors
  • Previously: required and fee for renewal
  • Update: Introduction of renewal fee waiver (details forthcoming by email to licensed installers).

• Licensing of System Cleaners
  • Previously: Required all trucks to be inspected
  • Update: Individual truck inspections removed.
    • Companies now licensed through certification course submission.
      • Active companies must submit NAWT (or EPCPH‑approved equivalent) certification.
      • Individual employees are not required to hold certifications.
    • Renewal fee waiver introduced; additional information will be emailed.

• Certification of System Designers
  • Previously: Not included
  • Update: New corrective education requirements apply when:
    • Soil reports require revision or EPCPH staff must meet onsite to resolve deficiencies.
    • Designs require resubmission or revision (applies to PEs and other professionals).
    • Evaluations will occur annually each December and cover the entire year.

• Certification of Operation & Maintenance Specialists / System Inspectors
  • Previously: required and fee for renewal
  • Update: Renewal fee waiver implemented (additional details forthcoming).

• Variance Procedure
  • Previously: Included
  • Update:
    • Variance prohibition added for non-functioning cesspools.
    • Clarification on BOH review for “No Closer Than” variances when documented records exist.

• Updates include rupture resistance, cemented soil classifications, and open profile pit requirements for certain zip codes.
• Implementation Note:
  • Existing soil reports lacking updated details will be accepted through December 2026 although it is encouraged to updated soils reports where able prior to submission.
  • Beginning January 1, 2027, reports must include cementation information; otherwise, revisions will be required.

• Increased design flow (additional 50 gpd) triggered when occupancy exceeds two persons per bedroom.
• Clarifications for ADUs and accessory living quarters.
• Addition of TL3ND treatment level to Table 6‑3.

• Property line setback reduction allowed from 10 feet to as little as 3 feet without BOH variance, when justified and compliant.
• Additional clarifications added to Tables 7‑1 and 7‑2.

• Changes include:
  • Clarification that hardening spray foams are not acceptable sealants for OWTS components.
  • Secondary safety features are now required in tank risers.
    • Implementation:All tanks installed under permits—repair, modification, new, or alteration—must comply.
      • Permits already issued, and permits issued for applications received prior to July 10, 2026, at 11:59PM, are exempt but encouraged to begin this installation practice immediately.
  • Floodplains and Floodways:
    • Clarifications of specific floodplains and floodways incorporated directly into the regulations.
    • All installations in floodplains or floodways must comply with the EPCPH Installation in Floodplain/Floodway Guidelines.

Changes include:

• All tanks must be a minimum of ¾ bedded prior to installation inspection.
• Cleanout requirements:
  • When a cleanout is not already installed outside the structure, a two‑way cleanout must be installed as close to the house as practical, but no more than 50 feet from the outside wall.
  • Implementation:This applies to all installations—repair, modification, new, or alteration for all existing permits as well as those to be issued.

• Schedule 40 Pipe Required
  • Beginning 5’ prior to the tank and all pipe beyond the tank
  • When variance to setbacks are approved

Changes:

• Several new soil types (FBR, DBR, R‑3) introduced and require professional engineer design.
• Soil types 4A and 5 require pressure distribution systems with a minimum of two alternating zones.
• Sand filters are not required for some Type R soils when using TL3ND treatment prior to dispersal.
• Timed dosing is no longer required in R‑2 soils.
• Introduction of fractured and deteriorated bedrock guidance for determining LTAR.
• High rock content soils must now include excavation difficulty in addition to percentage of rock content.
• Table 10‑3 includes updated sizing adjustment factors, separated for soil types 4A and 5.
• STA installation beneath paved surfaces is now allowed with:
  • Minimum TL2 treatment,
  • Load‑bearing accommodations,
  • Applicable Table 10‑3 sizing adjustments.
• Gravity flow pipe must be connected as close to center as possible on the distribution header while remaining offset from lateral lines.
  • Preference remains for use of a distribution box.
  • Implementation of this will be expected on all installations moving forward.
• Pressure distribution design parameters are consolidated into a single section—no major functional changes.
• Serial distribution designs are prohibited.
• When the total STA area (excluding endcaps) is 90% or more covered by chambers, the excavation equivalent may be used as the approved square footage.
• Fill material requirements:
  • When existing fill is present, all fill extending at least 12 inches below native grade must be removed.
  • Imported sand media must then be placed.
• Remediation technologies require an EPCPH permit and:
  • OWTS Certified Inspections must be submitted every 3 months for one year, unless otherwise specified.

Changes include:

• Media gradations must be dated within 4 months prior to installation and provided on official letterhead from the source gravel pit or independent laboratory.
• For adjacent sand filters, the bases must be at least 6 feet apart (sidewall to sidewall).
• Mound systems:
  • Now divided into three distinct categories:
    • All imported material above grade
    • Sand media entirely above grade but base below grade
    • Top installed both above and below grade
  • Numerous design considerations added, including:
    • • Appropriate LTAR selection based on sand elevation and wastewater strength
      • Consideration of linear loading rate based on effluent movement and site conditions
      • Requirements specific to wastewater strength received by the mound

• NDDS systems now require O&M oversight.
• Sampling guideline references added.
• Technology approval process streamlined since this is deferred to CDPHE.

• No changes.