Ordinance 3676-19 - Laserfiche WebLink

Re-establishment=The manipulation of the physical,chemical, or biological characteristics of a site with the goal of returning natural or historic functions to a former wetland. Activities could include removing fill material, plugging ditches, or breaking drain tiles.Activities could also involve breaching a dike to reconnect wetlands to a floodplain or return tidal influence to a wetland. Reestablishment results in a gain in wetland acres. Rehabilitation=The manipulation of the physical, chemical, or biological characteristics of a site with the goal of repairing natural or historic function of a degraded wetland. Activities could involve breaching a dike or reconnecting wetland to a floodplain or returning tidal influence to a wetland. Rehabilitation results in a gain in wetland function but does not result in a gain in wetland acres. Enhancement=The manipulation of the physical, chemical or biological characteristics of a wetland site to heighten, intensify or improve functions or to change the growth stage or composition of the vegetation present. Enhancement is undertaken for specified purposes such as water quality improvement,flood water retention or habitat.Activities typically consist of planting vegetation, controlling nonnative or invasive species, modifying the site elevation or the proportion of open water to influence hydroperiods, or some combination of these. Enhancement results in a change in some wetland functions and can lead to a decline in other wetland functions, but does not result in a gain in wetland acres. 'These ratios are based on the assumption that the rehabilitation or enhancement actions implemented represent the average degree of improvement possible for the site. Proposals to implement more effective rehabilitation or enhancement actions may result in a lower ratio, while less effective actions may result in a higher ratio.The distinction between rehabilitation and enhancement is not clear-cut. Instead, rehabilitation and enhancement actions span a continuum. Proposals that fall within the gray area between rehabilitation and enhancement will result in a ratio that lies between the ratios for rehabilitation and the ratios for enhancement. 5 Bogs are considered irreplaceable wetlands because they perform some special functions that cannot be replaced through compensatory mitigation. Impacts to such wetlands would therefore result in a net loss of some functions no matter what kind of compensation is proposed. a. Increased Mitigation Ratios.The city may increase the ratios under any one of the following circumstances: i. Uncertainty as to the probable success of the proposed restoration or creation; ii. Significant period of time between destruction and replication of wetland functions; iii. The proposed mitigation will result in a lower category wetland or projected losses in functions relative to the wetland being impacted; iv. The relocation is off-site or the replacement is with out-of-kind compensation; v. The wetland has been illegally filled or altered. b. Decreased Mitigation Ratios.The city may decrease these ratios under the following circumstances: i. Documentation by a qualified wetland specialist demonstrates that the proposed mitigation actions have a very high likelihood of success. ii. Documentation by a qualified wetland specialist demonstrates that the proposed mitigation actions will provide significantly greater functions than the wetland being impacted. iii. The mitigation actions are conducted in advance of the impact and have been shown to be successful. c. In lieu of the ratios described above, mitigation ratios may be calculated using the method in Calculating Credits and Debits for Compensatory Mitigation in Wetlands of Western Washington: Planning Commission Resolution 19-04 Page 42 Critical Areas March 19, 2019