Section 35.67.370 - Mobile home parks-Replacement of septic systems-Charges for unused sewer service(1) Cities, towns, or counties may not require existing mobile home parks to replace existing, functional septic systems with a sewer system within the community unless the local board of health determines that the septic system is failing.(2) Cities, towns, and counties are prohibited from requiring existing mobile home parks to pay a sewer service availability charge, standby charge, consumption charge, or any other similar types of charges associated with available but unused sewer service, including any interest or penalties for nonpayment or enforcement charges, until the mobile home park connects to the sewer service. When a mobile home park connects to a sewer, cities, towns, and counties may only charge mobile home parks prospectively from the date of connection for their sewer service. Chapter 297, Laws of 2003 is remedial in nature and applies retroactively to 1993.