soil amendments used for replanting in accordance with provisions of this <br /> section. <br /> (3) Construction of new septic drainfields. <br /> (4) Channelizing or straightening natural drainageways. <br /> (5) Removal or destruction of rare, threatened or endangered plant species, unless a <br /> conservation plan for the affected species is submitted by the applicant and <br /> approved by the planning director, in conjunction with the Oregon Department <br /> of Agriculture and the U.S. Fish and Wildlife Service. <br /> (6) Filling, grading, excavating, depositing soils imported from off-site, and the <br /> application of chemical herbicides, pesticides and fertilizers are prohibited <br /> unless they <br /> (a) Are directly related to a use permitted in the waterside protection area, <br /> (b) Address an imminent threat to public health and safety, or <br /> (c) Result in enhancement of water quality, and enhancement or maintenance <br /> of stormwater conveyance capacity, flood control capacity, groundwater <br /> discharge and recharge capacity and wildlife habitat. <br /> 9.4750 Conveyance of Stormwater Maintenance Easement. Within the /WP area, the city <br /> shall have the authority to require conveyance of a maintenance access easement for <br /> any natural or human made stormwater facility as a condition of approval for a site <br /> review or conditional use permit. Maintenance access easements shall be parallel to <br /> the stream or channel and shall be of sufficient width to allow a 20 foot wide <br /> maintenance access road along one side of the stream or channel. <br /> 9.4760 Exceptions. The planning director shall have authority to grant exceptions to the <br /> provisions of this overlay zone for uses and development within /WP areas subject to <br /> site review approval in accordance with the following provisions: <br /> (1) Criteria. Exceptions shall be granted only if the applicant clearly demonstrates <br /> in writing that either of the following exist: <br /> (a) The provisions of this overlay zone in conjunction with other city <br /> regulations, and circumstances peculiar to the property not self - imposed by <br /> the applicant, would prohibit any viable economic use of the property. <br /> (b) The /WP area as set forth in EC 9.4720 Waterside Protection Areas, <br /> occupies more than 33 percent of the development site area. <br /> (2) Process. To determine the extent to which an exception is allowed under EC <br /> 9.4760(1)(a), the planning director shall consider the following provisions: <br /> (a) Where practical, relax other setbacks in order to accommodate buffer <br /> setbacks as defined in EC 9.4720 Waterside Protection Areas. <br /> (b) If no economically viable use is feasible under (2)(a), relax /WP overlay <br /> zone requirements applicable to riparian areas as defined in EC 9.4720 <br /> Waterside Protection Areas, outside buffer setback areas. In this instance, <br /> enhancement of riparian vegetation within the buffer setback area shall be <br /> required consistent with applicable provisions from EC 9.2530 Natural <br /> Ordinance - 169 <br />