In addition to any applicable use regulations, development standards and review criteria contained in The Zoning Ordinance or other County ordinances, the following regulations shall apply to development subject to the Sensitive Resource Area Regulations:
1. Uses in wetlands shall be restricted to the following uses, not involving grading, filling, construction or placement of structures:
i. Aquaculture, provided that it does not harm the natural ecosystem.
ii. Scientific research, educational or recreational uses provided that they do not harm the natural ecosystem.
iii. Wetland restoration projects where the primary function is restoration of the habitat.
A buffer area of an appropriate size to protect the environmental and habitat values of the wetland shall be maintained around all identified wetland areas. Maps and supplemental information submitted as part of the application shall be used to determine the specific boundaries of the wetland and buffer. The California Department of Fish and Game and the United States Fish and Wildlife Service shall be consulted in such buffer determinations.
In the wetland buffer areas, permitted uses shall be limited to:
ii. Other improvements necessary to protect adjacent wetlands.
iii. All uses permitted in wetland areas.
b. Floodway. The development of permanent structures for human habitation or as a place of work shall not be permitted in a floodway.
1. In the floodway, permitted uses shall be limited to:
i. Agricultural, recreational, and other such low intensity uses provided, however, that no use shall be permitted which will substantially harm the environmental values of a particular floodway area; and
ii. Mineral extraction subject to an approved major use permit and reclamation plan, provided that mitigation measures were required which produce any net gain in functional wetlands and riparian habitat, and that the reclamation plan restores the site to its natural state, which would not create any increase in flood depths or velocities or changes in the boundary from those of the floodway prior to the mineral extraction.
2. Modifications to the floodway must meet all of the following criteria:
i. Concrete or rip-rap flood control channels are allowed only where findings are made that completion of the channel is necessary to protect existing buildings from a current flooding problem. Buildings constructed after enactment of this ordinance shall not be the basis for permitting such channels.
ii. Modification will not unduly accelerate the velocity of water so as to create a condition which would increase erosion (and related downstream sedimentation) or would be detrimental to the health and safety of persons or property or adversely affect wetlands or riparian habitat.
iii. In high velocity streams where it is necessary to protect existing houses or other structures, minimize stream scour, or avoid increase in the transport of stream sediment to downstream wetlands and other environmentally sensitive habitat areas, grade control structures and other erosion control techniques, including the use of rip-rap, that are designed to be compatible with the environmental setting of the river may be permitted.
c. Floodplain Fringe. All uses permitted by zoning and those that are allowable in the floodway are allowed in the floodplain fringe. Prior to granting a site plan required by this section for development, including permanent structures, grading, fill, deposit of soil or other material, or removal of natural vegetation within a 100-year floodplain fringe, all of the following criteria shall be met:
1. Fill shall be limited to that necessary to elevate the structure above the elevation of the floodway and to permit minimal functional use of the structure (e.g., fill for access ramps and drainage). If fill is placed in the floodplain fringe, the new bank of the creek shall be landscaped to blend with the natural vegetation of the stream and enhance the natural edge of the stream.
2. Any development below the elevation of the 100-year flood shall be capable of withstanding periodic flooding.
3. The design of the development incorporates the findings and recommendations of a site-specific hydrologic study to assure that the development (a) will not cause significant adverse water quality impacts related to quality or quantity of flow or increase in peak flow to downstream wetlands, lagoons and other sensitive habitat lands; and (b) neither significantly increases nor contributes to downstream bank erosion and sedimentation of wetlands, lagoons, or other sensitive habitat lands.
4. The proposed development shall be set back from the floodway boundary a distance equal to 15 percent of the floodway width (but not to exceed 100 feet) in order to leave an appropriate buffer area adjacent to the floodway. The setback may be greater if required by Paragraph 5.
Following review of a site-specific flood analysis, the floodplain setback required by this paragraph may be reduced by the Director of Planning and Development Services or the applicable hearing body, upon making all of the following findings:
i. Practical difficulties, unnecessary hardship, or results inconsistent with the general purposes of this Ordinance would result from application of the setback; and
ii. The reduction in setback will not increase flood-flows, siltation and/or erosion, or reduce long term protection of the floodway, to a greater extent than if the required setback were maintained; and
iii. The reduction in setback will not have the effect of granting a special privilege not shared by other property in the same vicinity; and
iv. The reduction in setback will not be materially detrimental to the public health, safety, or welfare, or injurious to the property or improvement in the vicinity in which the property is located; and
v. The reduction in setback will not be incompatible with the San Diego County General Plan.
5. In areas where the Director of Public Works has determined that the potential for erosion or sedimentation in the floodplain is significant, all proposed development shall be set back from the floodway so that it is outside the Erosion/Sedimentation Hazard Area shown on County Floodplain Maps. Development will be allowed in the Erosion/Sedimentation Hazard Area only when the Director of Public Works approves a special study demonstrating that adequate protection can be achieved in a manner that is compatible with the natural characteristics of the river.
6. Where appropriate, flowage and/or open space easements shall be used to ensure future development will not occur in the floodplain.
7. If the subject floodplain fringe land also constitutes wetlands, wetland buffer areas, sensitive habitat lands or significant prehistoric or historic site lands, the use restrictions herein applicable to such areas shall also apply.
d. Steep Slope Lands. No development, grading, excavation, or deposit of soil or other material, on Steep Slope Lands shall be permitted except as follows:
1. Project Design and Open Space to Protect Steep Slopes. In designing lot configuration on steep slope lands in all land use designations, parcels shall be created in a manner which minimizes encroachment onto steep slopes. Where 10 percent or more of a lot contains steep slope lands, that portion of the lot containing such lands shall be placed in an open space easement, unless the lot is equal to or greater than 40 acres.
The open space easement shall not include any area of encroachment within the limits of the encroachment table at subparagraph (i) below. The terms of the open space easement shall provide for sufficient encroachments necessary for access, clearing, and all exceptions to the encroachment limitations identified at subparagraph (ii) below. New agricultural operations with approved grading or clearing permits will also be allowed in such open space easements, provided any other type of sensitive lands present are protected as required by the applicable sections of this Ordinance.
i. For all types of projects the maximum encroachment that may be permitted into steep slope areas shall be as set forth in the following table. This encroachment may be further reduced due to environmental concerns or other design criteria.
Twenty-five Percent Slope Encroachment Allowance
ii. Notwithstanding the provisions of paragraph (i) above, the following types of development shall be allowed on steep slopes and shall not be subject to the encroachment limitations set forth above:
a) All public roads identified in the Mobility Element of the County General Plan or adopted Community or Subregional Plans, provided that findings are made by the hearing body approving the application that no less environmentally damaging alternative alignment or non-structural alternative measure exists.
b) Local public streets or private roads and driveways which are necessary for access to the portion of the site to be developed on slopes of less than twenty-five percent, provided no less environmentally damaging alternative exists. The determination of whether or not a proposed road or driveway qualifies for an exemption, in whole or in part, shall be made by the Director of Planning and Development Services based upon an analysis of the project site.
c) Public utility systems, provided that findings are made that the least environmentally damaging alignment has been selected.
d) Areas with native vegetation, which are cleared or trimmed to protect existing or proposed structures in potential danger from fire, provided that the area of such clearance is the minimum necessary to comply with applicable fire codes or orders of fire safety officials and that such slopes retain their native root stock or are replanted with native vegetation having a low fuel content, and provided further that the natural landform is not reconfigured.
e) Trails for passive recreational use according to approved park plans.
f) A minimum disturbed area of (i) twenty percent of the entire lot, or (ii) sufficient area to accommodate 3,000 square feet of building footprint (whichever is greater) shall be permitted to provide for reasonable use of existing lots.
g) Any ongoing existing agricultural operation, such as the cultivation, growing and harvesting of crops and animals. Land left fallow for up to three years shall be considered to be existing agricultural operations.
2. Waiver of Open Space Easement. The steep slope open space easement requirement may be waived when the authority considering the site plan application makes the following findings:
i. The slope is an insignificant visual feature and isolated from other land forms, or surrounding properties have been developed on steep slopes such that this project would be considered "infill;" and
ii. The property is zoned for .5 acre lots or smaller at the time the application was made, or a concurrent rezone has been filed; and
iii. The greater encroachment is consistent with the goals and objectives of the applicable community plan.
iv. Site Plan review is required, to ensure consistency of design with these regulations.
e. Sensitive Habitat Lands. Development, grading, grubbing, clearing or any other activity or use damaging to sensitive habitat lands shall be prohibited. The Board of Supervisors may allow development when all feasible measures necessary to protect and preserve the sensitive habitat lands are required as a condition of permit approval and where mitigation provides an equal or greater benefit to the affected species.
f. Significant Prehistoric and Historic Sites. Development, trenching, grading, clearing and grubbing, or any other activity or use damaging to significant prehistoric or historic site lands shall be prohibited except for scientific investigations with an approved research design prepared by an archaeologist certified by the Society of Professional Archaeologists.
(Added by Ord. No. 7630 (N.S.) adopted 05-23-89)
(Amended by Ord. No. 7967 (N.S.) adopted 9-11-91)
(Amended by Ord. No. 10162 (N.S.) adopted 8-3-11)
(Amended by Ord. No. 10204 (N.S.) adopted 3-28-12)
(Amended by Ord. No. 10222 (N.S.) adopted 9-25-12. Opr. 11-26-12)