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Community Development Commission


Published: April 04, 2024

Publication Date: April 4, 2024

To: All Interested Agencies, Groups, and Individuals

This is to give notice that the Sonoma County Community Development Commission (Commission) has determined that the following proposed action under consideration is located in the 100-year floodplain. The Commission will be identifying and evaluating practicable alternatives to locating the action in the floodplain, as well as potential impacts on the floodplain from the proposed action. This is required by Executive Order 11988, in accordance with the U.S. Department of Housing and Urban Development (HUD) regulations at 24 CFR 55.20 Subpart C Procedures for Making Determinations on Floodplain Management.

As proposed, the project qualifies as a federal undertaking in that the project seeks funds from HUD under the HOME Investment Partnership Program (HOME) for improvements to a partially developed site to provide two (2) units of affordable housing for low-income and very-low-income households. A federal environmental review is required and is being prepared pursuant to 24 CFR Part 58. The Commission is acting as the Responsible Entity (RE) under 24 CFR Part 58.

The proposed project to be developed by CommonSpace Community Land Trust (CLT) Sebastopol would be located at 1809 Cooper Road, Sebastopol, Sonoma County, California, on the approximate 3.09-acre parcel identified as Assessor’s Parcel Number (APN): 063-250-041 (Site). An unnamed creek is located along the western edge of the parcel; however, no wetlands are present at the Site.

The project involves improvements to the partially developed Site to provide two (2) affordable housing units for low-income and very-low-income households. Improvements would include remodeling the existing 1,422 square-foot single-family residence into a duplex by expanding the primary residence and converting an existing bedroom into a Junior Accessory Dwelling Unit (JADU),and constructing a new detached Accessory Dwelling Unit (ADU). With the proposed expansion, the single-family residence and JADU would be a total of 1,822 square feet. Expansion of the residence would occur within the previously disturbed area of the carport to be removed.

The 749 square-foot detached ADU would be ADA accessible and would have two (2) bedrooms. The ADU would be installed in a previously disturbed area and would be accessed via a gravel path. Aside from removal of the existing carport, no structures would be removed. Additionally, the on-site septic system that serves existing development would be improved through conversion of the leach field from a trench system to a sand mound system.

According to the Federal Emergency Management Agency’s (FEMA) Flood Insurance Rate Map (FIRM) panel number 06097C0718F (effective 10/16/2012), the majority of the Site is located within Zone “AE,” or the Special Flood Hazard Area (SFHA). The Site is approximately 3.09 acres, and the majority of the Site is located within the 100-year flood, aside from a small portion of the southeast corner of the Site that is located within Zone “X” (shaded). On October 17, 2023, a Letter of Map Amendment (LOMA) was granted by FEMA, finding the existing residential structure to be out of the flood zone.

There are three primary purposes for this notice. First, people who may be affected by activities in floodplains and those who have an interest in the protection of the natural environment should be given an opportunity to express their concerns and provide information about these areas. Commenters are encouraged to offer alternative sites outside of the floodplain, alternative methods to serve the same project purpose, and methods to minimize and mitigate impacts. Second, an adequate public notice program can be an important public educational tool. The dissemination of information and request for public comment about floodplains can facilitate and enhance Federal efforts to reduce the risks and impacts associated with the occupancy and modification of these special areas. Third, as a matter of fairness, when the Federal government determines it will participate in actions taking place in floodplains, it must inform those who may be put at greater or continued risk.

Written comments must be received by the Commission at the following address on or before April 19, 2024: Sonoma County Community Development Commission, 1440 Guerneville Road, Santa Rosa, CA 95403-4107, Attention: Veronica Ortiz-De Anda, during the hours of 8:00 AM to 5:00 PM, Monday-Friday or by calling (707) 565-7520. Comments can also be emailed to: A full project description and or request for additional information can also be made at the aforementioned contact information.