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Wetland quality (highly diverse wetlands or those that support rare species or particularly sensitive species may need protection from water level change as much, or more than, nutrient rich runoff) Wetland type (many wetland types do not typically have standing water so water quality protection benefits of a buffer are reduced - however, these same wetlands are more subject to pond excavations which can dramatically increase the need and value for a buffer) Some design elements are more important than others. We recommend the following: Native, non-invasive species are preferred for wildlife habitat and to ensure a diverse ecosystem that will be more resilient to pest and climatic threats. Deep rooted species preferred - native prairie species ideal. · Measure buffer width based on horizontal distance, and not ground distance - this results in wider buffers on steeper slopes and is easier to design on a plat. · The minimum buffer width should be 50 feet although I have seen some specifications in USDA guidelines that identify the minimum as 35 feet. Any buffer is better than none because by reducing the area of maintained lawn the amount of inputs (i.e. fertilizer) entering the water system is reduced. Other design considerations include: · Buffers around replacement wetlands where replacement credit is being received are managed differently than buffers around natural wetlands. · You may want to exclude the buffer area from setback requirements - some communities inadvertently have a setback from the buffer because they chose to put the buffer under a drainage easement - I find setbacks from buffers to be redundant. · You may want to include the buffer area when determining buildability depending on how your city classifies buildable area. · Within the MUSA you may want to give consideration for other activities such as rain gardens/berms that increase infiltration - allowing the buffer to be narrower. Management The purpose of a buffer is to provide a predefined benefit. Activities within the buffer must be limited to achieve the benefit. We recommend restricting the following activities: · No structures allowed · No mowing - though maintenance including thinning trees is allowed to increase stem density and improve wildlife habitat · No yard waste disposal No septic systems- wells are OK · No fencing within or around the buffer · No grading - unless to correct an erosion problem or similar issue · Removal of invasive species is desirable but often not enforceable - buckthorn is the biggest concern because it will shade out other species and leave the soil exposed to erosion Enforcement Enforcing compliance with buffer requirements will be the sole responsibility of the city. Consider the following: · Include the buffer within the drainage and utility easement for the same reasons that the wetland is included in the easement- a specific public benefit that must be maintained for the public good