Article 66.
BR Biotic Resource Combining District.
§ 26-66-005 Purpose.
§ 26-66-010 Development criteria.
§ 26-66-020 Critical habitat area.
§ 26-66-030 Riparian corridors.
Purpose: to protect biotic resource communities including critical habitat areas and riparian corridors for their habitat and environmental value and to implement the provisions of Sections 3.1 and 3.2 of the general plan open space element. (Ord. No. 4643, 1993.)
Sec. 26-66-010. Development criteria.
Maximum building heights, minimum lot areas and lot widths, yard requirements and maximum percentages of lot coverage shall comply with the requirements for the districts with which the BR regulations are combined unless otherwise provided herein. (Ord. No. 4643, 1993.)
Sec. 26-66-020. Critical habitat area.
The following provisions shall apply to properties within the BR district which are designated as critical habitat areas on Figures OS-5a through OS-5i, inclusive of the general plan open space element.
(a) A biotic resource assessment to develop mitigation measures may be required where the planning director determines that a discretionary project could adversely impact a designated critical habitat area.
(b) Building envelopes which avoid critical habitat areas shall be required on tentative maps accompanying major or minor subdivisions.
(c) Building permits shall require a minimum setback of fifty feet (50') from the edge of any wetlands which are within a designated critical habitat area, with the following exceptions:
(1) Existing farm buildings are exempt and may be expanded or modified, provided that such expansion or modification shall not encroach further into any wetland.
(2) The planning director may waive the setback if, after preparation of a biotic resource assessment, it is determined that either:
(i) Applying the setback makes an otherwise buildable parcel unbuildable; or
(ii) The structure is a noncommercial agricultural building and must be located adjacent to an existing farm complex for efficient farm operation. (Ord. No. 4643, 1993.)
Sec. 26-66-030. Riparian corridors.
The following provisions shall apply to properties within the BR district which are designated as riparian corridors on Figures OS-5a through OS-5i, inclusive, of the general plan open space element. These provisions are intended to be protective measures along selected streams which balance the need for agricultural production, urban development, timber and mining operations, and flood control, with preservation of riparian values.
Definitions. Riparian corridors designated in the general plan are defined as follows for purposes of this chapter:
(1) “Flatland riparian corridors” include the corridors adjacent to any streams which flow through predominantly flat or very gently sloping land, generally with alluvial soil. This classification excludes areas covered by (2) and (4).
(2) “Russian River Riparian Corridor” includes the corridor adjacent to any part of the Russian River which is neither located within the above urban riparian corridor nor within the jurisdiction of a city.
(3) “Upland riparian corridors” include the corridors adjacent to streams not included in categories (1), (2) and (4).
(4) “Urban riparian corridors” include those portions of designated corridors within urban residential, commercial, industrial or public/quasi-public land use categories.
(a) The BR district shall be applied to streamside conservation areas along designated riparian corridors. The outermost boundaries of streamside conservation areas within the BR zoning district as indicated on the zoning maps should be considered approximate in order to allow for parcel specific determinations of the appropriate classification of a riparian corridor as a flatland or upland corridor based upon more detailed analysis of the parcel topography, and for the purpose of this section, shall be measured from the top of the higher bank as determined by the Sonoma County water agency, for designated riparian corridors as follows:
(1) Urban riparian corridors, fifty feet (50');
(2) Russian River Riparian Corridor, two hundred feet (200');
(3) Flatland riparian corridor, one hundred feet (100');
(4) Upland riparian corridor, fifty feet (50').
(b) Except as allowed by subsection (c) of this section, structures, roads, utility lines, parking lots, planting of lawns, grading, fill or excavation shall be prohibited within any streamside conservation area. This prohibition may be waived if:
(1) It makes a lot unbuildable and vegetation removal is minimized;
(2) No significant disturbance of riparian habitat would occur; or
(3) The use involves only the maintenance, restoration or minor expansion of an existing structure.
The planning director may require a biotic resource assessment prior to waiver of this prohibition so that any potentially significant adverse effects on riparian habitat can be avoided or mitigated.
(c) The following uses where allowed by the base district with which this district is combined shall be considered within any streamside conservation area. Such uses are also subject to the requirements of the base district:
(1) Timber operations conducted in accordance with an approved timber harvest plan;
(2) Streamside maintenance carried out by or under the authorization of responsible flood control agencies or pursuant to a permit issued by said responsible agencies;
(3) Road crossings and street crossings, utility line crossings;
(4) Mining operations conducted in accordance with the county surface mining and reclamation ordinance;
(5) Permitted summer dams;
(6) Grazing and similar agricultural production activities not involving structures or cultivation, except as defined by subsection (7) below;
(7) Agricultural Cultivation.
(i) Located no closer than one hundred feet (100') from the top of the bank in the Russian River riparian corridor,
(ii) Located no closer than fifty feet (50') from the top of the bank in flatland riparian corridors,
(iii) Located no closer than twenty-five feet (25') from the top of the bank in upland riparian corridors,
(iv) The setbacks of subsections (c)(7)(i) through (iv) of this section may be reduced through the use permit process or through a plan approved by the planning director provided the owner includes appropriate mitigations for potential erosion, bank stabilization and biotic impacts;
(8) Selective vegetation removal as part of an integrated pest management program administered by the agricultural commissioner;
(9) Creekside bikeways, trails and parks within urban riparian corridors;
(10) Development authorized by waiver under subsection (b) of this section. (Ord. No. 4643, 1993.)