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"buildable area" only refers to the area above the 100~year floodplain. The entirety of this area may not be buildable due to setbacks and other requirements. AR-5 or larger: 1.00 acre AR-1, AR-2, RD-1: 0.50 acre RD~2: 0.25 acre RD-3, RD-4: 7,500 sq. It. RD~5 to RD-7: entire lot or 5,200 sq. ft., whichever is less entire area except parking lot, streets, and open common areas (re\o'iewed on a case-by~case basis) entire area except parking lot, streets, landscaping, unless pier foundations are approved (reviewed on a case~by.case basis) 2. For residential zoning, the area outside the I aD-year floodplain must be contiguous or reasonably situated to provide buildable area for a residence and associate structures. Examples of structures include swimming pools, sheds, barns, detached garages, and other outbuildings that are normally associated with residential development. 3. Buildable area above the lOa-year floodplain must be constructed prior to map recordation. Floodplain and/ or floodway easement will be required over the floodplain outside the buildable area. Exceptions may be made for parcel maps provided a condition of approval is attached to the map requiring site plan review prior to issuance of building permits. WRD [Sacramento County Water Resources Division] requirements, including locations of excavation and fill, limitation on fill in the floodplain, etc., will be clearly indicated in the conditional approval. RD-IO and denser: Commercial and industrial: ACCESS Discussion Minimum access is required for all newly created parcels to allow ingress~egress during storm events. This is required for emergency access and to avoid creating "islands" during normal flooding. The idea is to provide "reasonable" access, but what is reasonable is highly subjective. At a minimum, access should be above the IO-year flood elevation, to minimize the occurrences of restricted access. Policies 1. Vehicular access to the buildable area of newly created parcels must be at or above the lO-year flood elevation. Exceptions may be made when the existing public street from which access is obtained is below the lO-year flood elevation. 2. Watercourse crossings shall be minimized. Creating of lots that require watercourse crossing for single lots or that will likely encourage watercourse crossings to be built by property owners (lots with usable area on both sides of the watercourse) will not be allowed. Exceptions may be granted for Agricultural and Agricultural/Residential zoned parcels larger than five acres on a case~by~case basis. OPEN WATERCOURSE EASEMENTS Discussion The County is requiring fee title easements be dedicated over the laO-year floodplain on sites that are developed or subject to discretionary actions. Different types of easements vvill be required dependent on the flow situation vvith the specific floodplain. Dedication of the easement will be required to prevent any development within the floodplain that would impact flooding, including postdevelopment fencing, grading, 58 importation of fill, and construction of secondary structures. The easements are intended to provide some measure of assurance that the floodplain will not be significantly altered, thereby impacting flooding. Explanation of the conditional floodplain easement can be found in the Definitions section of these policies. . . . Easements ",'ill be required as conditions of discretionary actions, including rezone or map approval. Policies 1. Upon development of a site, including rezones, and certain applications for building or use permits, the following easements will be required to be dedicated to the County. a) Floodway easements will be required over the area of a watercourse necessary to pass the peak IOO-year flow at an elevation designated by the Water Resources Division. b) Floodplain easement will be required over the remainder of the lOO~year floodplain outside areas to be master planned or consistent with provisions of an adopted Drainage Master Plan, if the site will be fully built out under the proposed zoning. c) When a site is not being fully built out under the present zoning, or if a Drainage Master Plan has not yet been adopted, then a Conditional Floodplain Easement (see Definitions section) may be granted over that portion of the floodplain that is less than hvo feet below the 100~year water surface elevation. 2. Floodplain easements as set forth in policy l(b) and 1(c) above will not be required for Agricultural and Agricultural/Residential parcels except on a case~by~case basis. FENCING Discussion Fencing within the floodplain occurs frequently and can significantly increase flood elevation. This is due to the fences collecting debris and effectively creating a dam. Limited fencing will be allowed within the floodplain prm'ided that it does not create flow restrictions and allow for the free flow of water. The policies will not apply to Agricultural or Agricultural/Residential parcels greater than five acres, except where flood elevations are significantly impacted. Policies 1. Fencing will be prohibited within the floodway of a watercourse. Open fencing parallel to the flow direction may be allowed within the flood way on a case-by-case basis. 2. Fencing outside the flood way but within the conveyance area of a watercourse will be restricted to the least flow~ restrictive types of open fencing (three-strand "vire, three- board rail, etc.). Chain link, space board fencing, etc., will not be allowed. 3. Fencing outside the conveyance area of a watercourse but within the IOO-year floodplain will be restricted to fencing that allows the passage of ,vater. FILL IN THE FLOODPLAIN Discussion Reclaiming floodplain by importing fill has the effect of increasing flow dmV11stream. Importing fill into the existing floodplain removes floodplain storage. Water that may have otherwise ponded outside the effective flow area of a watercourse will be forced downstream instead, thereby increasing the flow and water surface elevations downstream. Merely replacing any fill with an offsetting amount of excavation will not ahvays be adequate to