16.50.470 Development Standards for Specific Species or Habitats.
(1) Endangered, Threatened, and Sensitive Species.
(a) No development shall be allowed within a habitat conservation area or buffer with which state or federally endangered, threatened, or sensitive species have a primary association.
(b) Whenever activities are proposed adjacent to a habitat conservation area with which state or federally endangered, threatened, or sensitive species have a primary association, such area shall be protected through the application of protection measures in accordance with a critical area report prepared by a qualified professional and submitted to the Director of Community Development. Approval for alteration of land adjacent to the habitat conservation area or its buffer shall not occur prior to consultation with the Washington Department of Fish and Wildlife and the appropriate federal agency.
(2) Wetland Habitats. All proposed activities within or adjacent to habitat conservation areas containing wetlands shall, at a minimum, conform to the wetland standards set forth in Sections 16.50.250 through 16.50.290, in addition to meeting the habitat conservation area standards in Sections 16.50.440 through 16.50.470.
(3) Riparian Habitat Areas.
(a) Activities Shall Not Degrade the Functions and Values of Riparian Habitat. Unless otherwise allowed in this Chapter, all structures and activities shall be located outside of the riparian habitat area. A proposed activity may only be permitted in a riparian habitat area if the applicant can show that the activity, including associated mitigation measures, will not degrade the functions and values of the riparian habitat area and other critical areas.
(b) Establishment of Riparian Habitat Areas. Riparian habitat areas shall be established for habitats that include aquatic and terrestrial ecosystems that mutually benefit each other and that are located adjacent to rivers, perennial or intermittent streams, seeps and springs.
(c) Classification. Streams are classified using the following Water Typing System described in WAC 222-16-031, as amended:
(i) Type S: Type S waters are shorelines of the state.
(ii) Type F: Type F waters are perennial or seasonal, fish bearing waters.
(iii) Type Np: Type Np waters are non-fish bearing perennial waters.
(iv) Type Ns: Type Ns waters are non-fish bearing seasonal waters.
(d) Standard Riparian Habitat Area Widths. Standard riparian habitat area widths are shown in Table 16.50.8 below. A riparian habitat area shall have the required width, unless a greater width is required pursuant to Paragraph 16.50.470(3)(e), or a lesser width is allowed pursuant to Paragraph 16.50.470(3)(f). Widths shall be measured outward, on the horizontal plane, from the ordinary high water mark or from the top of bank if the ordinary high water mark cannot be identified.
Stream Type | Standard Riparian Habitat Area Widths |
|---|---|
Type S: shorelines of the state | 250 feet |
Type F: perennial or seasonal fish bearing waters (South Fork of Palouse River, Missouri Flat Creek, Sunshine Creek, Paradise Creek, Dry Fork Creek, and Airport Road Creek) | 200 feet |
Type Np: non-fish bearing perennial waters Type Ns: non-fish bearing seasonal waters | 150 feet |
• For water-dependent developments, there is no minimum riparian habitat area width. Apply mitigation sequencing to avoid and minimize adverse impacts during development siting. • For all developments, riparian habitat area widths are the lesser of the distance indicated above, or (if present) the waterward edge of an improved public road or railroad intersecting the riparian habitat area. | |
(e) Increased Riparian Habitat Area Width. The standard riparian habitat area width shall be increased, as follows:
(i) when the Director of Community Development determines that the standard width is insufficient to prevent habitat degradation and to protect the structure and functions of the habitat area; and/or
(ii) when the Director of Community Development determines that the standard width is insufficient to protect human life and development from frequently flooded areas, geologically hazardous areas, or channel migration zones.
(f) Riparian Habitat Area Width Averaging. The Director of Community Development may allow the standard riparian habitat area width to be reduced in accordance with a critical area report only if:
(i) the width reduction will not reduce stream habitat functions, including those of non-fish habitat;
(ii) the width reduction will not degrade the habitat;
(iii) the proposal will provide additional habitat protection;
(iv) the total riparian habitat area of each stream on the development proposal site is not decreased;
(v) the width is not reduced by more than 25 percent in any one location;
(vi) the width reduction will not be located within another critical area or associated buffer; and
(vii) the reduced width is supported by the most current, accurate, and complete scientific and technical information available.
(g) Riparian Habitat Mitigation. Mitigation of adverse impacts to riparian habitat areas shall result in equivalent functions and values on a per function basis, be located as near the alteration as feasible, and be located in the same sub-drainage basin as the habitat impacted.
(h) Alternative Mitigation for Riparian Habitat Areas. The requirements set forth in this Section may be modified at the Director of Community Development’s discretion if the applicant demonstrates that greater habitat functions, on a per function basis, can be obtained in the affected sub-drainage basin as a result of alternative mitigation measures.
(i) Uses and Modifications Allowed in Riparian Habitat Areas. The following uses are allowed in riparian habitat areas provided that mitigation sequencing pursuant to Section 16.50.170 is demonstrated, and any adverse impacts to ecological functions are mitigated.
(i) Water-Dependent Uses. Consistent with the provisions of this Chapter, water-dependent uses, modifications and activities may be located in riparian habitat areas at the water’s edge.
(ii) Accessories to Water-Dependent Uses. Uses, developments and activities accessory to water-dependent uses should be located outside any applicable standard or reduced riparian habitat area unless at least one of the following is met:
aa. proximity to the water-dependent project elements is critical to the successful implementation of the facility’s purpose and the elements are supportive of the water-dependent use and have no other utility (e.g., a road to a boat launch facility, facilities that support aquaculture); or
bb. the proposed accessory would be located in a park or on other public lands where recreational development is already legally established, and the accessory would not conflict with or limit opportunities for other water-oriented uses; or
cc. the accessory use, development, or activity can be located upland of the water-dependent use; or
dd. the applicant’s lot has topographical constraints where no other location of the development is feasible (e.g., the water-dependent use or activity is located on a parcel entirely or substantially encumbered by the required buffer).
In these circumstances, uses and modifications accessory to water-dependent uses must be designed and located to minimize intrusion into the buffer.
(iii) Water-Oriented Public Access and Recreation Facilities. New development and redevelopment of water-oriented public access and recreation structures are allowed in riparian habitat areas provided the applicant can demonstrate that the design applies mitigation sequencing and appropriate mitigation is provided to ensure no net loss of ecological functions. The City may review and condition the project to fully implement the provisions of this Chapter.
(iv) Temporary Agricultural Equipment and Facilities. New agricultural equipment and facilities, excluding buildings, may be placed in a buffer if the following conditions are satisfied:
aa. placement of the equipment and facilities must support an existing agricultural use;
bb. the equipment and facilities may only be in the buffer on a temporary or seasonal basis, a maximum of eight (8) months in a running 12-month period;
cc. placement outside of a buffer is not feasible because it would be located on a property owned by another landowner or it would interfere with another agricultural or authorized use;
dd. the location of the proposed equipment and facilities is on an already altered site, and would not result in harm to or removal of native vegetation; and
ee. best management practices are utilized to prevent adverse impacts to water quality or other ecological functions.
(v) Shoreline Residential Access. A private access pathway constructed of pervious materials may be installed, a maximum of four feet wide, through the riparian habitat area to the ordinary high water mark. Impervious materials may be used as needed to construct a safe, tiered pathway down a slope. Raised boardwalks may also be constructed through wetland areas to reach the shoreline waterbody consistent with the provisions of this Chapter. A railing may be installed on one edge of the pathway, and shall be a maximum of 36 inches tall and of open construction. Pathways to the shoreline should take the most direct route feasible consistent with appropriate safety standards.
(j) Standards for Specific Activities in Riparian Habitat Areas. In addition to the general review procedures set forth in Section 16.50.130 and other applicable provisions of this Chapter, the standards below apply to specific activities proposed to be located within a riparian habitat area to ensure maintenance or enhancement of the functions and values of the affected habitat area.
(i) Clearing and Grading. Clearing and grading operations shall comply with the following standards:
aa. grading shall be conducted only when soil conditions are dry and the potential for erosion is low;
bb. tilling or modification of a wetland or wetland buffer is permitted only if it is conducted as part of an approved wetland alteration;
cc. the soil duff layer shall remain undisturbed to the maximum extent possible, and where feasible, any soil disturbed shall be redistributed to other areas of the project area;
dd. the moisture-holding capacity of the topsoil layer shall be maintained by minimizing soil compaction or reestablishing natural soil structure and infiltrative capacity on all areas of the project area not covered by impervious surfaces; and
ee. erosion and sediment control that meets or exceeds the standards set forth in the adopted stormwater management regulations shall be provided.
(ii) Shoreline Erosion Control Measures. New, replacement, or substantially improved shoreline erosion control measures shall maintain natural shoreline processes such that the project will not result in increased erosion or alterations to, or loss of, shoreline substrate within one-quarter mile (1,320 feet) of the project area.
(iii) Streambank Stabilization. Streambank stabilization to protect new structures from future channel migration shall be achieved through bioengineering or soft armoring techniques wherever possible.
(iv) Roads, Trails, and Bridges. Construction of trails, roadways, and road bridges shall comply with the following standards:
aa. the applicant shall demonstrate that there is no feasible alternative route with less impact on the environment, or that functions or values of the riparian habitat area would be enhanced by the project;
bb. any crossings shall minimize interruption of downstream movement of wood and gravel;
cc. road bridges shall be designed according to the Washington Department of Fish and Wildlife Water Crossing Design Guidelines, May 2013; and
dd. use of impervious materials for trails and associated viewing platforms shall be minimized.
(v) Utility Facilities. New utility lines and facilities shall comply with the following standards:
aa. fish and wildlife habitat areas shall be avoided to the maximum extent possible;
bb. installation of utilities across watercourses shall be accomplished by boring beneath the scour depth and hyporheic zone of the water body and channel migration zone, where feasible;
cc. utilities shall cross at an angle greater than 60 degrees to the centerline of the channel in streams or perpendicular to the channel centerline whenever boring under the channel is not feasible;
dd. crossings shall be contained within the footprint of an existing road or utility crossing where possible;
ee. the utility route shall avoid paralleling the stream or following a down-valley course near the channel; and
ff. the utility installation shall not increase or decrease the natural rate of shore migration or channel migration.
(vi) Public Flood Protection Measures. New public flood protection measures and expansion of existing ones may be subject to the approval of a Federal Biological Assessment by the federal agency responsible for reviewing actions related to a federally listed species.
(vii) In-stream Facilities. In-stream facilities, such as, but not limited to, high flow bypasses, sediment ponds, in-stream ponds, tide gates, dams, and weirs, may be allowed only as part of an approved watershed basin restoration project approved by the city and upon acquisition of any required state or federal permits. The structures shall be designed to avoid modifying flows and water quality in ways that may adversely affect habitat conservation areas.
(viii) Stormwater Conveyance Facilities. Stormwater conveyance structures shall comply with the following standards:
aa. the applicant shall demonstrate that no feasible alternatives with less impact exist;
bb. the structures shall incorporate fish habitat features; and
cc. vegetation shall be maintained and, if necessary, added adjacent to all open channels and ponds in order to retard erosion, filter out sediments, and shade the water.
(ix) On-Site Sewage Systems and Wells. On-site sewage systems and wells shall comply with the following standards:
aa. new individual wells and on-site sewage systems may be allowed only if accessory to an approved residential structure for which it is not feasible to connect to a public water or sanitary sewer system; and
bb. repairs to failing on-site sewage systems associated with an existing structure shall be accomplished by one of the following methods that results in the least impact to the environment: connection to an available public sanitary sewer system; replacement with a new on-site sewage system located in a portion of the site that has already been disturbed by development and is located landward as far as possible, provided the proposed sewage system is in compliance with the Whitman County Health Department; or repair of the existing on-site septic system. (Ord. 21-15 §6, 2021; Ord. 19-6 §29, 2019; Ord. 03-18 §48, 2003).