Chapter 18.60
USE REGULATION FOR “E-S” ENVIRONMENTALLY SENSITIVE OVERLAY DISTRICT
Sections:
18.60.030 Poor bearing capacity soils.
18.60.050 Aquifer recharge areas.
18.60.010 Purpose.
Within the “E-S” environmentally sensitive overlay district, areas are identified per Chapter 18.15 BHCC. This chapter shall prescribe permitted uses, conditional uses, and performance standards for those areas. Development within the overlay district must conform to the requirements of both the zoning district and the overlay district or the most restrictive of the chapter’s requirements. [Ord. 109, 2010; Ord. 36 § 17, 1995. Code 2009 App. A, § 17.]
18.60.020 Floodplains.
A. Intent. It is the intent of this section to promote the public health, safety and general welfare by minimizing those flood losses described in Chapter 18.55 BHCC, findings of fact, with provisions designed to:
1. Preserve and protect the natural character of the lands within this district, and their values for flood control and water holding capacity, maintenance of water quality, benefits of recharge of ground water, wildlife, recreation and conservation, reduced soil erosion and sedimentation, and woodland management;
2. Reserve sufficient floodplain area for the conveyance of flood flows so that flood heights and velocities will not be increased;
3. Restrict or prohibit uses which are dangerous to health, safety, or property in times of flood or which cause excessive increases in flood heights or velocities;
4. Require that uses vulnerable to floods, including public utilities which serve such uses, be protected against flood damage at the time of initial construction, or substantial improvement;
5. Protect individuals from buying lands which are unsuited for intended purposes because of flood hazards;
6. Reduce public expenditures for construction of flood control works, emergency action and postdisaster assistance;
7. Reduce loss of life, injury, and hardship due to floods; and
8. Assure that eligibility is maintained for property owners in the County to purchase flood insurance through the National Flood Insurance Program.
B. Warning and Disclaimer of Liability. The degree of flood protection required by this chapter is considered reasonable for regulatory purposes and is based on engineering and scientific methods of study. Larger floods may occur on rare occasions. Flood heights may be increased by manmade or natural causes, such as ice jams and bridge openings restricted by debris. This chapter does not imply that areas outside the floodplain or land uses permitted within such areas will be free from flooding or flood damages. This chapter shall not create liability on the part of Black Hawk County or any officer or employee thereof for any flood damages that result from reliance on this chapter or any administrative decision lawfully made thereunder.
C. Divisions of the Floodplain.
1. Floodway District (“F-W”) – General Intent. It is the intent of the floodway district (“F-W”) that the identified area is designed to carry flood waters and should be protected from developmental encroachment.
a. Principal Permitted Uses. The following uses shall be permitted within the floodway district to the extent they are not prohibited by any other ordinance (or allowed according to the underlying zoning district) and provided they do not require placement of structures, dwellings, factory-built homes, fill or other obstruction, the storage of materials or equipment, excavation, or alteration of a watercourse:
i. Agricultural uses such as general farming, pasture, grazing, outdoor plant nurseries, horticulture, viticulture, truck farming, forestry, sod farming, and wild crop harvesting, but not including livestock feedlots.
ii. Industrial commercial uses such as loading areas, parking areas, and airport landing strips.
iii. Private and public recreational uses such as golf courses, tennis courts, driving ranges, archery ranges, picnic grounds, boat launching ramps, swimming areas, parks, wildlife and nature preserves, game farms, fish hatcheries, shooting preserves, target ranges, trap and skeet ranges, hunting and fishing areas, hiking and horseback riding trails.
iv. Residential uses such as lawns, gardens, parking areas and play areas.
v. Such other open space uses similar in nature to the above uses.
b. Conditional Uses. The following uses which involve structures (temporary or permanent), fill, storage or materials or equipment may be permitted only upon issuance of a conditional use permit. Such uses must also meet the applicable provisions of the floodway district performance standards.
i. Uses or structures accessory to open space uses.
ii. Circuses, carnivals, and similar transient amusement enterprises.
iii. Extraction of sands, gravel, and other materials.
iv. Marinas, boat rentals, docks, piers, and wharves.
v. Utility transmission lines, underground pipelines.
vi. Other uses similar in nature to uses described above which are consistent with the provisions of the performance standards and the general spirit and purpose of this section.
c. Performance Standards. All floodway district uses allowed as a permitted or conditional use shall meet the following standards:
i. No use shall be permitted in the floodway district that would result in any increase in the 100-year flood level. Consideration of the effects of any development on flood levels shall be based upon the assumption that an equal degree of development would be allowed for similarly situated lands.
ii. All uses within the floodway district shall:
(A) Be consistent with the need to minimize flood damage.
(B) Use construction methods and practices that will minimize flood damage.
(C) Use construction materials and utility equipment that are resistant to flood damage.
iii. No use shall affect the capacity or conveyance of the channel or floodway or any tributary to the main stream, drainage ditch, or any other drainage facility or system.
iv. Structures, buildings and sanitary and utility systems, if permitted, shall meet the applicable performance standards of the shallow flooding (“S-F”) and floodway fringe (“F-F”) districts and shall be constructed or aligned to present the minimum possible resistance to flood flows.
v. Buildings, if permitted, shall have a low flood damage potential and shall not be for human habitation.
vi. Storage of materials or equipment that is buoyant, flammable, explosive or injurious to human, animal or plant life is prohibited. Storage of other material may be allowed if readily removable from the floodway district within the time available after flood warning.
vii. Watercourse alterations or relocations (channel changes and modifications) must be designed to maintain the flood carrying capacity within the altered or relocated portion. In addition, such alterations or relocations must be approved by the Department of Natural Resources.
viii. Any fill allowed in the floodway must be shown to have some beneficial purpose and shall be limited to the minimum amount necessary.
ix. Pipeline river or stream crossings shall be buried in the streambed and banks or otherwise sufficiently protected to prevent rupture due to channel degradation and meandering or due to the action of flood flows.
x. Mobile homes shall not be permitted.
xi. Recreational vehicles placed on sites within the special flood hazard areas on the community’s official map shall (A) be on the site for fewer than 180 consecutive days, and (B) be fully licensed and ready for highway use. A recreational vehicle is ready for highway use if it is on its wheels or jacking system, is attached to the site only by quick-disconnect type utilities and security devices, and has no permanently attached additions. A recreational vehicle that is accessory to a principal permitted use and is fully licensed and ready for highway use may be on the site for more than 180 consecutive days for storage purposes only and not living quarters.
2. Floodway Fringe District (“F-F”) – General Intent. It is the intent of the floodway fringe district that the identified area is designed to preserve and protect the natural character of the lands within the district and their values for flood control and water holding capacity. The areas within this district should be protected from developmental encroachment.
a. Principal Permitted Uses. The following uses shall be permitted within the “F-F” floodway fringe district to the extent they are not prohibited by any other ordinance (or underlying zoning district) and provided they do not require the placement of dwellings or factory-built homes. All uses shall meet applicable performance standards of the floodway fringe district.
i. Any use permitted in a floodway district as a principal permitted use.
b. Conditional Uses. The following uses involving structures (temporary or permanent), fill, storage of materials or equipment may be permitted only upon issuance of a conditional use permit. Such use must also meet the applicable provisions of the floodway fringe district performance standards.
i. Any conditional use permitted in a floodway district.
ii. Subdivisions and new or substantially improved residential buildings, in accordance with subsection (C)(2)(c) of this section.
c. Performance Standards. All uses must be consistent with the need to minimize flood damage and shall meet the following applicable performance standards:
i. All structures shall: (A) be adequately anchored (including factory-built homes) to prevent flotation, collapse or lateral movement of the structure, (B) be constructed with materials and utility equipment resistant to flood damage, and (C) be constructed by methods and practices that minimize flood damage.
ii. New or Substantially Improved Residential Buildings. New or substantially improved residential structures shall have the lowest floor, (including basements) elevated a minimum of three feet above the 100-year flood level. The preferred method of elevation shall be on piles, posts, piers or columns, or on walls or a crawl space. Enclosures created by a crawl space or solid walls below the base flood elevation shall only be used for building access, vehicle parking, and storage of materials that have low damage potential. Enclosures shall be constructed of flood resistant materials and utilities must be raised a minimum of three feet above the base flood elevation. Enclosures must be floodable and have openings as provided in subsection (C)(2)(c)(iv) of this section. The methods used must be adequate to support the structure as well as withstand the various forces and hazards associated with flooding. Elevation on fill shall be discouraged to protect flood storage capacity and to prevent flood heights from increasing due to a loss of flood storage capacity. When permitted, elevation on fill shall be upon compacted fill which shall, at all points, be no lower than three feet above the 100-year flood level and extend at such elevation at least 18 feet beyond the limits of any structure erected thereon. Elevation on fill shall not be permitted when the natural grade is more than two feet below the base flood elevation unless compensatory storage is created to offset any loss of flood storage. Compensatory storage shall not include excavation areas that create ponds or low lying areas likely to have their storage capacity exhausted by nonflood waters. All new or substantially improved residential buildings shall be provided with a means of access that will be passable by wheeled vehicles during the 100-year flood.
iii. Nonresidential Buildings. All new or substantially improved nonresidential buildings shall have the lowest floor (including basement) elevated a minimum of three feet above the 100-year flood level, or, together with attendant utility and sanitary systems, be floodproofed to such a level. When floodproofing is utilized, a professional engineer registered in the state of Iowa shall certify that the floodproofing methods used are adequate to withstand the flood depths, pressures, velocities, impact and uplift forces and other factors associated with the 100-year flood; and that the structure, below the 100-year flood level, is watertight with walls substantially impermeable to the passage of water. A record of the certification indicating the specific elevation (in relation to North American Vertical Datum 1988) to which any structures are floodproofed shall be maintained by the Zoning Administrator.
iv. All New and Substantially Improved Structures.
(A) Fully enclosed areas below the “lowest floor” (not including basements) that are subject to flooding shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of flood waters. Designs for meeting this requirement must either be certified by a registered professional engineer or meet or exceed the following minimum criteria:
(1) A minimum of two openings having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding shall be provided.
(2) The bottom of all openings shall be no higher than one foot above grade.
(3) Openings may be equipped with screens, louvers, valves, or other coverings or devices; provided, that they permit the automatic entry and exit of flood waters.
Such areas shall be used solely for parking of vehicles, building access and low damage potential storage.
(B) New and substantially improved structures must be designed (or modified) and adequately anchored to prevent flotation, collapse, or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy.
(C) New and substantially improved structures must be constructed with electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities that are designed and/or located so as to prevent water from entering or accumulating within the components during conditions of flooding.
v. Factory-Built Homes.
(A) Factory-built homes, including those placed in existing factory-built home parks or subdivisions, shall be anchored to resist flotation, collapse, or lateral movement by providing over-the-top and frame ties to ground anchors. Specific requirements are that:
(1) Over-the-top ties be provided at each of the four corners of the factory-built home with two additional ties per side at intermediate locations for factory-built homes 50 feet or more in length or one such tie for factory-built homes less than 50 feet in length;
(2) Frame ties be provided at each corner of the home with five additional ties per side at intermediate points for factory-built homes 50 feet in length or four such ties for homes less than 50 feet in length;
(3) All components of the anchoring system be capable of carrying a force of 4,800 pounds; and
(4) Any additions to the factory-built home be similarly anchored.
(B) Factory-built homes, including those placed in existing factory-built home parks or subdivisions, shall be elevated on a permanent foundation such that the lowest floor of the structure is a minimum of three feet above the 100-year flood level.
(C) Factory-built homes not being placed in existing factory-built home parks or subdivisions shall be placed on lots or pads elevated so that the lowest floor of the factory-built home will be a minimum of three feet above the 100-year flood level. In addition, the tie-down specifications enumerated within subsection (C)(2)(c)(v) of this section must be met and adequate surface drainage and access for a hauler must be provided. New factory-built home parks, expansions to existing factory-built home parks, and factory-built home parks where the repair, reconstruction or improvement of the streets, utilities, and pads equals or exceeds 50 percent or more of the value of the streets, utilities and pads before the repair, reconstruction or improvement has commenced shall provide:
(1) Lots or pads that have been elevated so that the lowest floor of the factory-built homes will be a minimum of three feet above the 100-year flood level;
(2) Adequate surface drainage;
(3) Access for a hauler; and
(4) Ground anchors for factory-built homes.
vi. Utility and Sanitary Systems.
(A) All new and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of flood waters into the system as well as the discharge of effluent into flood waters. Wastewater treatment facilities shall be provided with a level of flood protection equal to or greater than three feet above the 100-year flood elevation.
(B) On-site waste disposal systems shall be located or designed to avoid impairment to the system or contamination from the system during flooding.
(C) New or replacement water supply systems shall be designed to eliminate infiltration of flood waters into the system. Water supply treatment facilities shall be provided with a level of protection equal to or greater than three feet above the 100-year flood elevation.
(D) Utilities such as gas and electrical systems shall be located and constructed to minimize or eliminate flood damage to the system and the risk associated with such flood damaged or impaired systems.
vii. Recreational vehicles placed on sites within the special flood hazard areas on the community’s official map shall either (A) be on the site for fewer than 180 consecutive days, (B) be fully licensed and ready for highway use, or (C) meet the permit requirements for “manufactured homes” of this section. A recreational vehicle is ready for highway use if it is on its wheels or jacking system, is attached to the site only by quick-disconnect type utilities and security devices, and has no permanently attached additions.
viii. Storage of materials and equipment that are flammable, explosive or injurious to human, animal or plant life is prohibited unless elevated a minimum of three feet above the 100-year flood level. Other material and equipment must either be similarly elevated or: (A) not be subject to major flood damage and be anchored to prevent movement due to flood waters, or (B) be readily removable from the area within the time available after flood warning.
ix. Flood control structural works such as levees, flood walls, etc., shall provide, at a minimum, protection from a 100-year flood with a minimum of three feet of design freeboard and shall provide for adequate interior drainage. In addition, structural flood control works shall be approved by the Department of Natural Resources.
x. No use shall affect the capacity or conveyance of the channel or floodway of any tributary to the main stream, drainage ditch, or other drainage facility or system.
xi. Subdivisions (including factory-built home parks and subdivisions) shall be consistent with the need to minimize flood damages and shall have adequate drainage provided to reduce exposure to flood damage. Development associated with subdivision proposals shall meet the applicable performance standards. Subdivision proposals intended for residential development shall provide all lots with a means of vehicular access that will remain dry during occurrence of the 100-year flood.
xii. The exemption of detached garages, sheds, fences, flag poles and similar structures from the 100-year flood elevation requirements may result in increased premium rates for insurance coverage of the structure and contents; however, said detached garages, sheds, fences, flag poles and similar accessory type structures are exempt from the 100-year flood elevation requirements when:
(A) The structure shall not be used for human habitation.
(B) The structure shall be designed to have low flood damage potential.
(C) The structure shall be constructed and placed on the building site so as to offer minimum resistance to the flow of flood waters.
(D) Structures shall be firmly anchored to prevent flotation, which may result in damage to other structures.
(E) The structure’s service facilities such as electrical and heating equipment shall be elevated or floodproofed.
(F) A professional engineer registered in the state of Iowa shall certify that these requirements are met.
3. General Floodplain District (“F-P”) – General Intent. The “F-P” general floodplain district reflects those areas which would be inundated during a 100-year flood, but for which specific flood elevations and floodway and floodway fringe limits have not been established. It is the intent of the “F-P” district to impede the restrictions and performance standards of the “F-W” and “F-F” districts after a determination is made to identify the floodway and floodway fringe areas on an individual basis. The areas within this district should be protected from development encroachment.
a. Principal Permitted Uses. As specified, principal permitted uses for either the “F-W” floodway or the “F-F” floodway fringe districts.
b. Conditional Uses. As specified, conditional uses for either the “F-W” floodway or the “F-F” floodway fringe districts.
c. Performance Standards. The applicant shall provide the Department of Natural Resources with sufficient technical information to make a determination as to whether the land involved is either partly or wholly within the floodway or floodway fringe and to determine the 100-year flood elevation.
i. All uses or portions thereof to be located in the floodway as determined by the Department of Natural Resources shall meet the applicable standards of the “F-W” floodway district.
ii. All uses or portions thereof to be located in the floodway fringe as determined by the Department of Natural Resources shall meet the standards of the “F-F” floodway fringe district.
4. Shallow Flooding (Overlay) District (“S-F”).
a. Principal Permitted Uses. All uses within the shallow flooding district shall be permitted to the extent that they are not prohibited by any other ordinance (or underlying zoning district) and provided they meet the applicable performance standards of the shallow flooding district.
b. Performance Standards. The performance standards for the shallow flooding district shall be the same as the performance standards for the floodway fringe district with the following exceptions:
i. In shallow flooding areas designated as an AH zone on the flood insurance rate map, the minimum floodproofing/flood protection elevation shall be equal to the elevation as specified on the rate map.
ii. In shallow flooding areas designated as an AH zone on the flood insurance rate map, require adequate drainage paths around structures on slopes, to guide flood waters around and away from proposed structures. [Ord. 112, 2011; Ord. 109, 2010; Ord. 104, 2009; Ord. 82, 2003; Ord. 63, 2001; Ord. 36 § 17(A), 1995. Code 2009 App. A, § 17(A).]
18.60.030 Poor bearing capacity soils.
A. Intent. It is the intent of this section to promote the public health, safety and general welfare by minimizing losses that may occur by not considering soil potentials. For structures, soils should be sufficiently stable that cracking or subsidence from setting or shear failure of the foundation does not occur. Severe ratings were determined for each soil from estimates of the shear strength, compressibility, shrink-swell potential, soil texture, plasticity and in-place density, potential frost action, soil wetness, depth to seasonal high water table, depth to bedrock, slope, presence of large stones and boulders, susceptibility to flooding and erosion hazard.
B. Principal Permitted Uses. All uses within the “E-S” environmentally sensitive overlay district identified as poor bearing capacity soils shall be permitted to the extent that they are not prohibited by any other ordinance, other provisions of this title or underlying zoning district, and provided they meet the applicable performance standards for poor bearing capacity soils.
C. Conditional Uses. All uses within the “E-S” environmentally sensitive overlay district identified as poor bearing capacity soils shall be permitted to the extent that they are not prohibited by any other ordinance, other provisions of this title or underlying zoning district conditional use and provided they meet the applicable performance standards for poor bearing capacity soils.
D. Performance Standards. All uses upon poor bearing capacity soils allowed as permitted or conditional use shall meet the following standards:
1. All structures to be placed upon soils rated as severe for building site development, Soil Survey of Black Hawk County, Iowa, shall submit to the Zoning Administrator a plan reviewed by the District Soil Conservationist. Said plan shall be in a manner prescribed by the District Soil Conservationist and may include but is not limited to: methods of soil conditioning, special design applications, increase in construction effort, site planning or required maintenance.
2. All water and sewer systems to be placed upon soils rated as severe for sanitary facilities, Soil Survey of Black Hawk County, Iowa, shall submit to the Zoning Administrator a plan approved by the County Environmental Health Supervisor. Said plan shall be in a manner prescribed by the County Environmental Health Supervisor and may include but is not limited to: special design applications, increase in construction effort, methods of site conditioning, site planning and required maintenance. [Ord. 36 § 17(B), 1995. Code 2009 App. A, § 17(B).]
18.60.040 Excessive slopes.
A. Intent. It is the intent of this section to promote the public health, safety and general welfare by minimizing soil loss that may occur by not considering the effects of soil erosion upon an individual site, adjacent lands and the surface and subsurface water quality of the County. For the development of structures upon slopes exhibiting erosion hazard, methods shall be employed that will: (1) preserve the aesthetics of the site and surrounding area, (2) offer protection from mass movement, (3) limit soil transport, and (4) decrease excess water runoff and sedimentation.
B. Principal Permitted Uses. All uses within the “E-S” environmentally sensitive overlay district identified as excessive slopes shall be permitted to the extent that they are not prohibited by any other ordinance, other provisions of this title or underlying zoning district, and provided they meet the applicable performance standards for excessive slopes.
C. Conditional Uses. All uses within the “E-S” environmentally sensitive overlay district identified as excessive slopes shall be permitted to the extent that they are not prohibited by any other ordinance, other provisions of this title or underlying zoning district conditional uses and provided they meet the applicable performance standards for excessive slopes.
D. Performance Standards. All uses upon excessive slopes allowed as permitted or conditional use shall meet the following standards:
1. All structures to be placed upon soils identified as excessive slopes, BHCC 18.15.040(B)(1)(b), shall submit to the Zoning Administrator a plan reviewed by the District Soil Conservationist. Said plan shall be in a manner prescribed by the District Soil Conservationist and may include but is not limited to: methods of soil stabilization, special design applications, maintaining of the vegetation cover, increase in construction effort, site planning or required maintenance.
2. All water and sewer systems to be placed upon soils rated as excessive slopes shall submit to the Zoning Administrator a plan reviewed by the County Environmental Health Supervisor. Said plan shall be in a manner prescribed by the County Environmental Health Supervisor and may include but is not limited to: special design applications, increase in construction effort, methods of site conditioning, site planning and required maintenance. [Ord. 36 § 17(C), 1995. Code 2009 App. A, § 17(C).]
18.60.050 Aquifer recharge areas.
A. Intent. It is the intent of this section to promote the public health, safety and general welfare by minimizing the effects that unplanned land development may have on the quality of water found in subsurface aquifers. Water recharge occurs throughout Black Hawk County; however, the areas identified in BHCC 18.15.040(B)(1)(c) have the greatest potential for recharge. Aquifers are replenished in recharge areas: areas of interchange between the aquifer and the earth’s surface and the point where precipitation and surface water infiltrate the aquifer. Wise planning of development in recharge areas is particularly important because of the danger of polluting the water supply.
B. Principal Permitted Uses. All uses within the “E-S” environmentally sensitive overlay district identified as aquifer recharge areas shall be permitted to the extent that they are not prohibited by any other ordinance, other provisions of this title or underlying zoning district and provided they meet the applicable performance standards for aquifer recharge areas.
C. Conditional Uses. All uses within the “E-S” environmentally sensitive overlay district identified as aquifer recharge areas shall be permitted to the extent that they are not prohibited by any other ordinance, other provisions of this title or underlying zoning district conditional uses and provided they meet the applicable performance standards for aquifer recharge areas.
D. Performance Standards. All uses upon aquifer recharge areas allowed as permitted or conditional uses shall meet the following standards:
1. All structures and uses to be placed upon aquifer recharge areas shall submit to the Zoning Administrator a plan reviewed by the District Soil Conservationist. Said plan shall be in a manner prescribed by the District Soil Conservationist and may include but is not limited to: methods of soil conditioning, special design applications, increase in construction effort, site planning, required maintenance, or appropriate methods to protect the aquifer.
2. All water and sewer systems to be placed upon aquifer recharge areas shall submit to the Zoning Administrator a plan reviewed by the County Environmental Health Supervisor. Said plan shall be in a manner prescribed by the County Environmental Health Supervisor and may include but is not limited to special design applications, increase in construction effort, methods of site conditioning, site planning, required maintenance, alternative design or methods of safe disposal.
3. Structures or Uses Prohibited. The following structures or uses shall be prohibited within the “E-S” environmentally sensitive overlay district, identified as aquifer recharge areas, BHCC 18.15.040(B)(1)(c):
a. Sanitary landfills.
b. Livestock feedlots.
c. Junk or salvage yards.
d. Kennel, dog, including private.
e. Stables, private and public.
f. Gasoline or filling stations or convenience store.
g. The manufacturing, compounding, processing, packaging or treatment of cosmetics, pharmaceutical, and food products.
h. Chemical manufacture or wholesale storage of chemicals.
i. Explosive manufacture or storage.
j. Fertilizer and/or agricultural chemical manufacture, blending or storage.
k. Garbage, offal or dead animal reduction or dumping.
l. Petroleum, flammable liquids and gases, and minerals or their products, exploration, refining or storage.
m. Slaughter houses and stockyards, distillation of bones, glue, size or gelatin manufacture, hide treatment and storage.
n. Smelting of tin, copper, zinc, or iron ores.
o. Storage of industrial waste, sludge, oils, chemicals and solvents. [Ord. 36 § 17(D), 1995. Code 2009 App. A, § 17(D).]
18.60.060 Surface waters.
A. Intent. It is the intent of this section to promote the public health, safety and general welfare by minimizing the effect that unplanned land development may have on the quality of water found in surface rivers, streams, lakes, ponds, reservoirs, and wetlands. Surface waters are sensitive areas. Developmental activity within and adjacent to the watercourse has profound effects on stream hydrology, channel geometry and water quality. It shall be the intent of this section to establish a floating buffer zone upon and adjacent to surface waters within the County not afforded the protection offered under BHCC 18.60.020, Floodplains. It is the purpose of this section to maintain safe water quality within the surface waters by retaining areas within the floating buffer zone in its natural condition.
B. Principal Permitted Uses. All uses within the “E-S” environmentally sensitive overlay district identified as surface waters, shall be permitted to the extent that they are not prohibited by any other ordinance, other provisions of this title or underlying zoning district, and provided they meet the applicable performance standards for surface waters.
C. Conditional Uses. All uses within the “E-S” environmentally sensitive overlay district identified as surface waters shall be permitted to the extent that they are not prohibited by any other ordinance, other provisions of this title or underlying zoning district conditional uses and provided they meet the applicable performance standards for surface waters.
D. Performance Standards.
1. Establishment of the Surface Water Floating Buffer Zone. All surface waters not afforded the protection offered under BHCC 18.60.020, Floodplains, shall establish upon and adjacent to it a floating buffer zone. For purposes of this chapter, the “floating buffer zone” shall be defined as a land strip adjacent to the shoreline necessary to maintain existing water quality. The width of the floating buffer zone shall be a minimum of 100 feet unless upon the determination of the Zoning Administrator it is determined that the surface waters can be protected on less than the minimal distance. The Administrator shall consider: (a) the soil type and how surface water filters into the ground, (b) the types and amount of vegetative cover and how it stabilizes the soil, and/or (c) the slope of the land with the buffer zone and how significant it is for retaining sediment from reaching the streams.
2. All structures and uses, including septic systems, to be placed upon surface waters and adjacent floating buffer zones shall submit to the Zoning Administrator a plan reviewed by the District Soil Conservationist and County Environmental Health Supervisor. Said plan shall be in a manner prescribed by the District Soil Conservationist and County Environmental Health Supervisor and may include but is not limited to special design applications, staged development practices, the use of temporary vegetation and mulching, permanent vegetation seedings, retention of the natural condition, wherever feasible, alterations caused by unusual topography, the construction of sediment basins or silt traps, and required maintenance.
3. Structures or Uses Prohibited. The structures and uses listed under BHCC 18.60.050(D)(3) shall be prohibited within the “E-S” environmentally sensitive overlay district, identified as surface waters. [Ord. 36 § 17(E), 1995. Code 2009 App. A, § 17(E).]