You are viewing an archived code
1. Boise River System Overlay Districts: To ensure that development along the river is sensitive to fish and wildlife, the riparian area, recreation and flood protection.
A. Goals:
(1) Flood Protection:
(a) To ensure protection from flooding.
(b) To allow for conveyance the 100-year flood without property damage or loss of life.
(2) Fish And Wildlife:
(a) To preserve, protect, and enhance the abundance and diversity of fish, wildlife and riparian resources.
(b) To control runoff and pollution so as to protect water quality of the river and its tributaries.
(3) Recreation Amenities:
(a) To protect the Boise River as a public asset to the city and a major amenity for its citizens.
(b) To maintain the Boise River Greenbelt.
(4) Development Opportunities:
(a) To ensure that development is designed to enhancement and protect rivers riparian, fish, wildlife and recreational values.
(b) To provide and maintain continuous public access to and along the river including appropriate facilities for parking of bikes and motor vehicles.
B. Boise River System Management District Boundaries; Subdivision Plat Notes; Ordinances And Regulations To Comply With:
(1) All subdivisions which include land that lies within the floodplain shall have the following note on the face of the plat: "This subdivision includes lands which are in the floodplain and are subject to the regulations of Chapter 11-08, Flood Hazard Regulations and 11-05-06.1, Boise River System Overlay Districts. The Planning Division should be consulted for details."
(2) The following ordinances and regulations of uses within the district apply:
Land Classification | Floodplain Ordinance (Ch. 11-08) | Use Standards of Boise River Ordinance | Mitigation Section of Boise River Ordinance (11-05-06.1.I) | Enhancement Section of Boise River Ordinance (where appropriate) (11-05-06.1.J) | Boise River Development System Permit Required (11-03-04.19) |
Class A | Yes | Yes | Yes | Yes | Yes |
Class B | Yes | Yes | Yes | Yes | Yes |
Class C | Yes | Yes | No | Yes | Yes |
C. Map And Boundaries:
(1) Boundary Map: [Reserved]
(2) Districts: The Boise River System overlay district shall include the following areas:
(a) Floodway And Floodway Fringe Overlay Districts: Lands within the 100-year floodplain boundaries adjacent to the Boise River, including lands designated within the Floodway (F) and Floodway Fringe (FF). These boundaries adjacent to the Boise River are determined by the FEMA Flood Boundary and Floodway Map. A copy of this map is available at the Development Services Department. The Director with recommendation from the City Engineer shall provide boundary interpretations where necessary.
(b) Alluvial Overlay District: Tributary and Foothill Gulch floodplains and associated alluvial fans (AO zones) standards are addressed in Chapter 11-08, Flood Hazard Regulations.
(3) Boundary Descriptions:
(a) Floodway (F) District Boundary Description: The Floodway District shall have the boundaries as follows: The Channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than one foot, as shown in the Flood Insurance Study for Boise City, Idaho.
(b) Flood Fringe (FF) District Boundary Description: The Floodway Fringe District shall have boundaries as follows: The area between the floodway boundary and the boundary of the 100 Year Flood.
(c) Area Of Shallow Flooding (AFS) District Boundary Description: The Area of Shallow Flooding District shall have boundaries as area shown on the Flood Insurance Rate Map as an AO zone with base flood depths from one to three feet where a clearly defined channel does not exist, where the path of flooding is unpredictable and indeterminate, and where velocity flow may be evident.
D. A, B, And C Lands And Waters Classifications: The BRS overlay district includes lands and waters that provide natural resource functions and values including the preservation of fish and wildlife amenities shall be classified as "Class A, B, or C lands and waters."
(1) Class A, B, And C Lands And Waters Established:
(a) Located in the Planning Division Office is a set of master maps delineating class A, B, and C lands and waters. The precise boundaries shall be determined on a case-by-case basis based on available maps, studies, outside agency input and on-site inspections.
(b) The Boise River Fish and Wildlife Habitat Study, (Sather-Blair, et al, 1983), shall be used as a reference that provides objectives for preservation and management actions for Class A and Class B areas.
(2) Class A Lands And Waters - Extremely Important For Preservation: Class A lands and waters provide extremely important habitats for fish and wildlife and for flood control and protection. The objective is to preserve and protect these lands for their benefits to fish and wildlife in general and to protect Bald Eagle, Great Blue Heron, trout, and water fowl habitats in particular. These areas include, but are not limited to:
(a) Floodways;
(b) Areas with a high degree of plant community diversity;
(c) Black cottonwood riparian plant community;
(d) Riparian forests;
(e) Scrub-shrub wetlands;
(f) Emergent wetlands within the floodplain (exclusive of working irrigation canals);
(g) A 300 foot radius around Great Blue Heron rookeries;
(h) Eagle winter habitat which includes lands within 200 feet of the 6500 c.f.s. line, as determined by the Public Works Department based on their monitoring of annual flows, east of Walnut Street on the north side of the river and east of Phase 4 of the River Run Subdivision on the south, and forested wetlands east of these points;
(i) Lands within the riparian setback lands and waters;
(j) The banks of side channels and tributary stream areas within the jurisdiction of this overlay district;
(k) Islands within the river;
(l) Trout spawning waters;
(m) Riparian areas of tributary streams within the jurisdiction of this overlay district including channels that convey floodwaters and areas that meet the definition of wetlands; and
(n) The Barber Pool Natural Preserve.
(3) Class B Lands And Waters - Moderately Important For Preservation: Class B lands and waters provide good potential for improvements to natural resource functions and values. Development should improve natural resource functions and values and avoid negative. Class B lands and waters include, but are not limited to:
(a) Agricultural lands;
(b) Gravel pit ponds and small lakes; and
(c) Intermittent tributary streams.
(4) Class C Lands - Least Important For Preservation: Class C lands provide limited fish and wildlife habitat. Development should provide landscaping and habitat improvements. These areas include, but are not limited to:
(a) Public and private parks where current uses preclude enhancement of fish and wildlife habitat;
(b) Diversion dams;
(c) Residential and commercial developments;
(d) Lands surrounding gravel ponds;
(e) Subdivided properties;
(f) Former industrial areas; and
(g) Vacant lands in urban centers.
E. Setbacks: Setbacks are intended to protect and preserve the river; Greenbelt; Great Blue Heron rookeries; eagle perching, feeding, and loafing areas; and riparian areas.
(1) Boise River Setback: The setback for structures and parking areas is 70 feet from the 6500 c.f.s. line of the Boise River or 5 feet from the boundary of all dedications or easements granted to the City for greenbelt purposes in excess of 65 feet.
(2) Greenbelt Setback: The greenbelt setback for structures and parking areas is 70-feet measured landward from the 6500 c.f.s. setback line.
(3) Great Blue Heron Rookeries Setback: 300 feet around Great Blue Heron rookeries. Rookeries shall be designated by the city and the Idaho Fish and Game Department.
(4) Eagle Perching, Feeding, And Loafing Setback: 200 feet from the 6500 c.f.s, east of Walnut Street along the north side of the Boise River, and east of Phase 4 of the River Run subdivision along the south side of the Boise River.
(5) Riparian Setback:
(a) Tier 1 Waterway: A side channel with a width of less than 15 feet or with a flow of less than five c.f.s. shall have a riparian setback of 20 feet.
(b) Tier 2 Waterway: A side channel at least 15 feet wide or with a flow of between 5 to 150 c.f.s. shall have a riparian setback of 25 feet.
(c) A minimum of 15 feet shall be maintained between the riparian setback and structures to allow for lawns and patios.
F. Allowed Uses And Improvements: The following uses and improvements are allowed in Class A lands and waters areas subject to the standards for uses, mitigation and enhancement provisions set forth in this chapter. All uses not explicitly listed are prohibited from the Class A lands and waters area.
(a) Signs (non-commercial);
(b) Restrooms and snack bars (except for existing uses;
(c) River bridges and paved access to river bridges;
(d) Fish and wildlife habitat improvements;
(e) Irrigation weirs, diversion dams, and inlets;
(f) Water inlets to supply domestic water;
(g) Greenbelt structures under existing bridges;
(h) Greenbelt paths or non-paved pedestrian paths that may provide limited access to the river and may run into or through lands designated as Class A habitat areas.
(i) Paved bicycle paths, limited to:
i. Existing paths;
ii. The Lander Street sewage treatment plant path;
iii. The Warm Springs park area pedestrian path and bridge and;
iv. Where an existing railroad right-of-way is already located or that may require, donated, or used as a bicycle path;
(j) Natural parks;
(k) Bank and channel stabilization projects;
(l) Hydro-electric and flood protection dams;
(m) Selected public piers and beaches;
(n) Public utility lines such as water and sewer lines;
(o) Storm drain outlets and detention basins;
(p) Water pump facilities;
(q) Gravel extraction including reuse of gravel extraction lands;
(r) One housing unit per 20 acres or legal non-conforming lot;
(2) Class B Lands And Waters And Class C Lands: Uses allowed in Class B and Class C areas are limited to those listed in Table 11-06.1.
G. Standards:
(1) Standards Applicable To All Development Within The Boise River System Overlay District:
(a) Emergent Wetlands: In recognition of their importance and their scarcity, emergent wetlands shall be preserved as follows:
i. Emergent wetlands surrounded by Class B or Class C lands may be replaced with a wetland of equal size, provided that the created emergent wetland has the same or greater degree of natural resource functions and values as did the impacted emergent wetland.
ii. The emergent wetland may be relocated anywhere on the project site, except within Class C lands.
iii. If the emergent wetland is relocated to a site within existing Class A lands, then the land area of Class A lands and waters shall be enlarged by an amount no less than the size of the impacted emergent wetland.
(b) Enhancement Of Water Resources: Proposals to use or create a water amenity shall be design to accommodate wetland and riparian functions and waterfowl, wildlife, trout, or warm water fish habitats.
(c) Parks And Open Spaces:
i. Intense activity portions of parks shall be located outside of Class A lands.
ii. Open spaces such as parks, golf courses, greenbelt areas, parking lots, etc., within the floodplain shall be designed and operated to flood and provide storage capacity during flood flows in excess of 6500 c.f.s.
(d) Emergency Access: New developments shall include provisions for emergency access as determined by the Boise Fire Department.
(e) Greenbelt Access: Developments shall provide for public access to the Boise River greenbelt and public parking for bicycles and motor vehicles.
(f) Landscaping: Landscaping shall utilize native or naturalized plant materials that provide wildlife food and shelter. Manicured landscaping and lawns are prohibited in Class A lands and in riparian areas and setbacks.
(g) Bank And Channel: Bank or channel stabilization measures (e.g., rip- rap, drop structures, large cobble) shall include over-planting with shrubs and trees and the deliberate enhancement of fish habitat.
(h) Screening Requirements:
i. Structures shall be screened from view from the Greenbelt and the river with landscaping that will grow to a height of at least 20 feet within ten years.
ii. Parking areas located between the structure and the Boise River shall be screened from view by landscaping or decorative fencing at least five feet in height.
iii. Appropriate landscaping should be utilized to screen habitat areas from new development.
(i) Construction Fencing: Fencing shall be installed where construction activities abut a riparian area.
(2) Additional Standards Applicable To Class A Lands And Waters:
(a) Class A areas within a development or subdivision shall be preserved in single common ownership through a conservation easement or other method approved by the city.
(b) The removal of living or dead vegetation from the floodway shall not be permitted unless:
i. The vegetation poses a threat to persons or property;
ii. The vegetation contributes to a dangerous restriction of the flow of floodwater; or
iii. The removal of vegetation is part of an approved mitigation and enhancement plan.
(c) Removal of vegetation shall be confined to the minimum necessary, while still maintaining the natural riparian areas. Removal of vegetation is subject to approval by the Planning Director after review and recommendation by the Urban Forestry Division of the Boise City Parks and Recreation Department.
(d) Emergency situations under (2)(a) and (b) above may require actions to be taken before the Director can be contacted. If that is the case, then the action taken shall be reported to the Director and mitigation efforts shall be taken if the Director requires them.
(3) Additional Standard Applicable To Class B Lands And Waters: Development shall improve natural resource functions and values and shall mitigate negative impacts.
(4) Additional Standard Applicable To Class C Lands: Development plans shall provide for habitat improvements and landscaping to create screens and buffer between wildlife habitat areas and new.
H. Conditions For Permits:
(1) Conditions may be attached that:
(a) Require compliance with applicable specifications, standards or requirements of the Idaho Department of Water Resources, Army Corps of Engineers, the Idaho Fish and Game Department, U.S. Fish and Wildlife Service, Environmental Protection Agency, Boise City, or other agencies.
(c) Require landscaping consistent with the objectives of the Greenbelt or the extension of the natural setting of the river.
(d) Limit reclamation of eroded stream banks in the floodway and require overflow channels to remain open.
(e) Limit construction to certain periods of time.
(f) Require certification by a licensed engineer that conditions have been fulfilled.
I. Mitigation:
(1) Purpose:
(a) To offset negative impacts of a proposed development on the natural resource functions and values in Class A and B lands and waters.
(b) Mitigation goals for Class A and B lands will be no net loss of existing natural resource functions and values associated with flood protection, fish and wildlife habitat, recreation and other goals of the Comprehensive Plan and Boise River Plan.
(2) Natural Resource Functions And Values: Natural resource functions and values are:
(a) Water quality,
(b) Habitat for fish and wildlife,
(c) Nutrient retention and removal,
(d) Channel stability,
(e) Food chain support,
(f) Flood storage and de-synchronization,
(g) Groundwater recharge and discharge,
(h) Recreation,
(i) Aesthetics, and
(j) Cultural resources.
(3) Mitigation Measures And Sequencing For Class A, B, and C Lands And Waters: The mitigation sequence will be examined in the order listed below. Several mitigation measures may be used in combination to provide the greatest protection to the resource. Different mitigation sequencing may be used provided extensive evidence is submitted and adequately demonstrates the impacts and public benefits available. The burden shall be on the applicant to demonstrate compliance with the minimum standards described in this Section.
(a) Mitigation Measures For Class A And B Lands And Waters: Mitigation measures from the most to the least preferable are:
i. Avoid adverse impacts by selecting alternative alignments or locations.
ii. Minimize impacts by limiting encroachments, using less intrusive construction techniques, or other methods.
iii. Restore the impact area to as near its original condition as possible.
iv. In-kind on-site compensation.
v. In-kind off-site compensation.
(b) Mitigation Measures For Class C Lands And Waters: Mitigation is not required. Development in Class C lands shall not adversely affect adjacent and nearby habitat in Class A or Class B lands.
(4) Procedures For Development Of Mitigation Plan:
(a) Generation Of Field Data: To accurately describe existing conditions, constraints, and their magnitude, existing natural resource functions and values will be assessed by the applicant. This assessment must be provided with the project application for review by the city along with a comprehensive technical plan to mitigate for impacts to natural resource functions and values, or to enhance natural resource functions and values.
(b) Early Coordination With Resource And Regulatory Agencies: Consultation with government agencies that have resource responsibilities must be initiated by the applicant as soon as practicable to determine the natural resource functions and values existing within the area requiring a Boise River System development permit. Consultation shall also include a discussion of the presence of threatened and endangered species, and species of special concern; fish and wildlife habitat requirements and their sensitivity to disturbance; and measures needed to mitigate for project related impacts or to enhance existing habitat. Consultation shall be documented.
(c) Comprehensive Mitigation Design: Proposed modifications to Class A and B lands and waters shall include:
i. Preliminary Mitigation Plan: A preliminary site plan identifies the location and quality of existing natural resources, impacts to those resources attributable to the proposed project, and proposed mitigation measures.
ii. Final Mitigation Plan:
A. Upon approval of the Boise River System development permit a final site plan shall be developed by the applicant that includes a detailed description, plan view, profile, and typical sections of the mitigation project. The final site plan will fully describe proposed changes to the resource and the materials and methods used to accomplish mitigation.
B. The final site plan may be offered to the state and federal agencies for review. Comments of these agencies will be fully considered by the city in its determination of whether the final site plan is in accordance with the Boise River System development permit.
(d) Performance Monitoring: The applicant shall monitor the performance of constructed mitigation improvements for a minimum period of 18 months unless otherwise fixed by the PZC. Acceptable performance shall be judged by comparing measured values to previously agreed upon standards.
J. Enhancement:
(1) Purpose: To encourage innovative development design to increase the quantity and improve the quality of existing natural resource functions and values.
(2) Enhancement Plans: Enhancement plans may be submitted but are not required as part of an application for a Boise River System development permit.
(3) Enhancement Design Standards:
(a) Enhancement Of Class A, B, And C Waters:
i. Enhancement Of Waters Held By The Idaho Department Of Fish And Game: Enhancement or creation of water amenities that use waters held by Idaho Department of Fish and Game shall be designed for the propagation and perpetuation of fish and wildlife resources.
ii. Enhancement Of Non-Idaho Department Of Fish And Game Waters: Enhancement or creation of water amenities not held by Idaho Department of Fish and Game may be designed to enhance fish and wildlife resources or to provide a visual amenity.
(b) Enhancement Of Class A, B, And C Passive Open Space Lands:
i. Class A Passive Lands: Class A passive open space lands shall be designed with the primary intent of providing enhancement to fish, wildlife and riparian resources with specific design or attention given to eagles, Great Blue Heron, trout, and water fowl. Vegetation shall be predominantly native or naturalized plant species.
ii. Class B And C Passive Open Space Lands: Class B and C passive open space lands should be designed to encourage the creation of fish, wildlife, and riparian resources and to create transition between natural areas and areas of more intense development. Vegetation may be a combination of native or naturalized vegetation and ornamental or exotic species.
iii. Native And Naturalized Vegetation: Native and naturalized vegetation should be located near established or created habitat areas and may transition to more ornamental species towards or within the development.
iv. Waiver Of Standards:
A. In order to provide an incentive for higher quality and more extensive enhancement plans, waivers of zoning and subdivision standards may be requested.
B. Waivers may be granted by the PZC or Council on enhancement plans that have been designed in accordance with this section and that the enhancement plan is in compliance with the Boise River System overlay district.
C. Waiver of standards may be approved when evidence presented meets the following conclusions of law:
D. That the proposed enhancement plan is in compliance with the applicable standards of Section 11-05-06.1.I of this chapter.
E. That the proposed enhancement plan complies with all local, state and federal laws and regulations.
F. That the waivers requested ensure a benefit to the public.
v. Waivers Examples:
A. The waiver of sidewalk standards for the construction of pedestrian, bicycle or nature trails that functionally replace the sidewalk. Provision of pedestrian pathways is encouraged on both sides of streets.
B. Reduction in street width standards to minimize impervious surfaces and to provide more land for vegetation and habitat improvements, provided, however, that private streets are to be discouraged.
C. Density transfers and clustering of uses to provide larger areas for habitat improvements.
D. Permit stream and irrigation system waivers from the design requirements of the subdivision provisions of this Code.
E. Permit fencing waivers from irrigation and streams as required in the subdivision provisions of this Code.
F. Permit waivers of drainage standards, as long as drainage and water quality goals are met.
G. Permit flexibility in the enhancement of existing marginal Class A lands by permitting enhancements that improve the river riparian values.
H. Waivers that address public safety considerations.
I. Flexibility in lot size and setback standards to provide large areas increasing habitat. Any waiver or variance from setback requirements under this overlay district must be shown to be required by legal necessity (a taking would otherwise occur) or to promote and enhance public safety, or that strict compliance with the setback in a given area would result in more damage to the habitat and environment than would granting the waiver or variance under the provisions of this and other overlay district(s) or other Code provisions.
(4) Procedures For Development Of Enhancement Projects:
(a) The same field data required to satisfy Section 11-05-06.1.I(4) shall be gathered and used to aid in the design of the enhancement plan.
(b) A combined mitigation and enhancement preliminary plan may be submitted if the plans clearly designate that features fulfill the mitigation requirements and that features fulfill the enhancement plan. Enhancement features may be considered part of a mitigation plan only if such features meet the standards of Sections 11-05-06.1.I(1) and (3).
(5) Performance Monitoring: The applicant shall monitor the performance of constructed enhancements for a minimum period of 18 months unless otherwise fixed by the PZC. Acceptable performance shall be judged by comparing measured values to standards that were previously agreed-upon.