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Vil The key element of these recommendations involves developing a plan which contains an inventory of wetlands by vegetation type which then can be placed in a sensitivity group. The purpose of this grouping is to indicate what level of protection is needed and, therefore, indicate the detail of planning needed. A guide to acceptable levels of hydrologic change is presented. For some wetlands this means no change and for others there could be a range of acceptable levels. The more sensitive the wetlands, the more we need to identify existing and proposed land use in the watershed. Land use changes create the effects on hydrology and on pollutants. For most LGUs, this guidance recommends some concepts in hydrologic analysis to determine the effect of the present and proposed development. Most local metropolitan governments analyze flood and. drainage events. A great number of LGUs now analyze the 2.0 - 2.5 inch. rainfall for pollutant treatment. The guidance recommends that LGUs analyze small storm hydrology to understand the hydrologic impacts to sensitive wetlands, streambank erosion, and pollutant treatment. Storms which are less than 1.25 inches of rainfall depth contribute a large portion of annual runoff and pollutant loads. There are also differences in the runoff chazacteristics and sources that the LGUs should be aware of when analyzing~flood routing. Through State Executive Order 91-3, Minnesota State Agencies were instructed to strictly apply the principles of no-net-loss of wetlands in the conduct. of all their activities which affect wetlands. This policy was essentially codified in statute with the passage of the Wetland Conservation Act of 1991. With passage of the Wetlands Conservation Act and subsequent rules, the no-net-loss sequencing process of avoidance, minimize and compensate wetland losses was focused on wetland draining and filling activities. This document provides guidance on avoiding and minimizing wetland losses resulting from storm water so as to meet wetland protection goals. This guidance provides a sequence of decisions made by the developer or governmental agency in order to avoid, minimize and mitigate the impacts of a project. The recommended sequence avoids impacts by design, layout, and site specific action that do not change the basic hydrologic cycle or pollutant loading, a constant theme of all regulatory agencies. The guidance stresses specific measures that help to avoid discharges which will destroy sensitive wetlands, and to bypass or fingerprint the especially sensitive or protected azeas. Pondng is often not enough. Special measures may be needed to reach the recommended criteria of "no change" in ambient conditions. Ponds and other measures should be analyzed for their impacts and adjustments made until acceptable protection can be attained. The guidance should also convey the message that mitigation of unavoidable impacts does not occur if you adopt the process of simply replacing wetlands acre per acre. An analysis of values and functions must. be made on a site specific basis. The replacement of values and functions should be analyzed "value for value" and "function for function." The guidance points out that when approached as an opportunity and not only as a requirement, mitigation provides the opportunity to enhance or benefit the community as you mitigate losses.