kane county stormwater technical guidance manual - Kane County, IL

as wetlands that are impacted on the on-site wetlands. The summary table
on this drawing should include the acreage to be disturbed, the acreage to be
mitigated, the mitigation ratio and the total mitigation acreage.
Specifications for construction, monitoring and maintenance shall be included
with the mitigation plan and should include specifications for rough and final
grading, types of soils to be used for creation of the wetland mitigation, plant
materials to be used, how they will be procured, and from what sources.
Specifications should also include water control structures, specifications
related to the planting plan including scientific and common names, rates of
seeding or spacing, as appropriate, and any special planting provisions
necessary for a successful wetland mitigation.
Wetland mitigations shall contain a minimum of two wetland plant
communities. These plant communities must be appropriate for the site on
which they are contained and be a naturally occurring wetland type within
Kane County. This includes, but is not limited to wet prairie, emergent marsh,
floating vascular, shrub-scrub, wooded, forested floodplain, sedge, meadow
wet meadow, fen or calcareous seep, submerged aquatic, and mudflat
annual. It should be noted that certain plant communities including, fens,
submerged aquatic environments, hemi-marsh, and mudflat annuals will be
more difficult to establish or measure their performance. Thus, to attain the
goal FQI, performance standards may be more difficult to meet than for other
plant communities.
The maintenance and monitoring provisions of the wetland mitigation plan are
included in technical guidance for §1506. Maintenance and monitoring plan
shall at a minimum include an annual work schedule describing each task in
detail and its expected effect, the time of year it will be performed, and any
measure of success of the technique as employed. Changes to the mitigation
and monitoring plan shall be approved by the Director as necessary.
All wetland mitigation plans shall be designed to contain a minimum of two
wetland plant communities as described previously and open water shall not
constitute greater than 20% of the entire wetland mitigation facility. As noted
previously, detention storage can only be used for wetlands being mitigated
with and FQI less than seven. In compensatory storage areas, the limits
remain described as in §1502 and §1503.
§ T1505 Buffer Requirements for Wetland Mitigation Facilities
Buffers are required around the edges of wetland mitigation facilities and
these will be in accordance with the Tables described in §416 for the various
wetland communities. No buffer is required between a wetland mitigation
facility and an adjacent wetland that is preserved on site. A buffer is required
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