17-33 SITE IMPROVEMENTS, UTILITIES AND LIMITATIONS.

All proposed development in flood hazard areas shall be reviewed to determine that:

a. Such proposals are consistent with the need to minimize flood damage and will be reasonably safe from flooding.

b. Where the proposed development has more than fifty (50) lots or is larger than five (5) acres and base flood elevations are not included on the FIRM, the base flood elevations shall be determined in accordance with Section 17-15.2(a).

c. All public utilities and facilities, such as sewer, gas, electric, communications, and water systems are located and constructed to minimize or eliminate flood damage.

d. Adequate drainage is provided to reduce exposure to flood hazards; in Zones AH and AO, adequate drainage paths shall be provided to guide floodwater around and away from proposed structures. (Ord. #256-2021, S2 (303-1))

All new and replaced sanitary sewer facilities, private sewage treatment plants (including all pumping stations and collector systems) and on-site waste disposal systems shall be designed in accordance with Chapter 7, ASCE 24, to minimize or eliminate infiltration of floodwaters into the facilities and discharge from the facilities into flood waters, and impairment of the facilities and systems. (Ord. #256-2021, S2 (303-2))

The Clearlake Municipal Code is current through Ordinance 286-2026, passed April 2, 2026.

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Ch. XVII, Art. III Flood Resistant Development | Clearlake Municipal Code

All new and replaced water supply facilities shall be designed in accordance with the provisions of Chapter 7, ASCE 24, to minimize or eliminate infiltration of floodwaters into the systems. (Ord. #256-2021, S2 (303-3))

Development, site improvements and land disturbing activity involving fill or regrading shall not be authorized in the floodway unless the floodway encroachment analysis required in Section 17-15.3(a) demonstrates the proposed work will not result in any increase in the base flood level during occurrence of the base flood discharge. (Ord. #256-2021, S2 (303-4))

Subject to the limitations of these regulations, fill shall be designed to be stable under conditions of flooding including rapid rise and rapid drawdown of floodwaters, prolonged inundation, and protection against floodrelated erosion and scour. In addition to these requirements, when intended to support buildings and structures, fill shall comply with the requirements of the building code. The placement of fill intended to change base flood elevations, change floodway boundaries, or change boundaries of flood hazard areas shown on FIRMs shall be subject to the requirements of Section 17-15.4. (Ord. #256-2021, S2 (303-5))