Lake County official details local changes to align with Colorado Regulation 43

Torsten Smith, Lake County OWTS environmental health specialist, presented a county webinar explaining proposed local updates to onsite wastewater treatment system (OWTS) regulations to comply with Colorado Department of Public Health and Environment (CDPHE) updates to Regulation 43.

The changes are intended to bring Lake County into conformity with state requirements adopted last year. "The state of Colorado's CDPHE has adopted new regulation 43 updates," Smith said, adding that the state gave local counties one year from the June 15 adoption date to adopt compliant local regulations. He said the Board of Health will hold a formal adoption hearing on April 30 at 1:00 p.m.; if the board approves the draft, the regulations would take effect June 15.

Why it matters: The revisions affect permit requirements, testing and design standards for septic systems and related onsite wastewater methods. Smith said the changes will alter what engineers must submit to the county, clarify allowable system types for rocky soils and tighten material and licensing requirements that affect homeowners, contractors and short-term rental operators.

Key changes Smith highlighted include:

- Testing and certification: Section 43.4F1 will require residual head ("squirt") tests be included in engineer certification documents. Smith warned this is a new, locally meaningful change: "We have not been doing that in our current inspections. So that will be a new thing with the reg changes," and the test may require the installer to provide on-site power to run a pump for pressurized systems.

- Soil classification: Table 10-1A in Regulation 43 adds "fractured bedrock" and "deteriorated bedrock" categories, which will affect long-term acceptance rates and the range of approved systems for rocky soils.

- System design: Section 43.10F3A prohibits serial distribution systems in new construction; existing serial systems are not being removed but may not be used for new installations.

- Materials: Section 43.9D1D2 requires schedule 40 PVC within 5 feet of tanks.

- Sand media reporting: The state now requires sand gradation data to be provided in engineer designs prior to permitting (Section 43.11C2D4) so the county can verify sand source and particle analysis.

- Short-term rentals and seepage pits: Under local Section 1.13, short-term rentals must have a valid inspection within the last three years to keep a license; Smith said previous exceptions for older licenses have expired and that seepage pits are no longer allowed for commercial short-term rental properties, meaning existing seepage pits must be replaced with modern soil treatment areas.

- Local discretion and optional choices: Appendix A contains optional local choices; Section 43.71 now allows local agencies to determine certain property-line setback reductions in straightforward cases without a variance, while complex cases will still go to the board of health.

Smith said many of the local edits are limited to wording and authority changes — reflecting that the OWTS program moved from environmental health to Community Planning and Development (CPD) — and that more substantive or novel items (including vault privies, composting or incinerating toilets and commercial event facility rules) will be studied during a Phase Two moratorium and public-engagement process. "This moratorium was set up to give us more time to plan it out and to figure out what kind of oversight we would need for new programs," he said, and invited community members and experts to provide input through open houses and the county's public comment form.

During Q&A, Smith clarified inspection and documentation practices. In response to a question about soil profile holes, he said Lake County has historically relied on engineers' reports rather than requiring profile holes to remain open for county inspection. On sand gradation, he said the county expects sand gradation documentation with the engineer design submitted prior to installation and permitting, not as a post-installation final report. On the squirt test, Smith reiterated it will be a new requirement locally and could be difficult on sites without power: "The installer will need to have power to perform a water test."

Next steps: The webinar will be posted on the county website and a public comment form is available for written feedback. Smith provided contact information on the site for follow-up. The Board of Health adoption hearing is scheduled for April 30 at 1:00 p.m.; Smith said that if the board signs the current draft it would be effective June 15. The county intends to continue moratorium work and public engagement on alternative systems afterward.

Contact information and supporting documents, including the redline of Regulation 43 and the appendix of optional choices, are available on the Lake County OWTS webpage.