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These standards are for the reconstruction, modification or new construction of bridges, culvert crossings and roadway approaches that are located within the regulatory floodplain.
(A) A proposed new structure shall not result in an increase of upstream flood stages greater than one-tenth foot, when compared to the existing conditions for all flood events, up to and including the base flood event, unless contained within the channel banks or recorded easements. The evaluation must be submitted to IDNR-OWR for review and issuance of a permit.
(B) If the proposed new structure will increase upstream flood stages greater than one-tenth foot, the applicant must contact IDNR-OWR for a dam safety permit or waiver. The Administrator shall be copied on all related correspondence.
(C) A restrictive bridge or culvert may be altered to increase the conveyance of the base flood, if an impact analysis is completed and approved in writing by the Administrator, and all other required regulatory approvals are obtained.
(D) Velocity increases must be mitigated by use of appropriate measures to avoid scour, erosion and sedimentation at the structure.
(Ord. 2019-03, passed 4-15-2019)
(A) Before any development in or near waters of the U.S., or in or near a wetland delineated on the NRCS Wetland Inventory Maps, U.S. Fish and Wildlife Service National Wetland Inventory Map, or if the Administrator considers that a wetland is present through visual inspection, a written report identifying and evaluating the boundaries, location, limits, area and quality of all onsite wetlands shall be submitted. The presence and limits of wetland areas shall be determined by a wetland delineation conducted in accordance with the 1987 Corps of Engineers Wetland Delineation Manual. Before any development on agricultural land, in addition to the onsite delineation required under the provisions listed herein above, a farmed wetland delineation conducted in accordance with the National Food Security Act Manual methodology must be performed.
(B) The quality of the wetlands shall be evaluated based upon the Flora Quality Index (FQI).
(C) The approximate location, extent and relative quality of wetlands within 50 feet of the site shall be identified and included in the written report, if the wetland is downstream of the development such that the run off could negatively affect the quality or health of the wetland. The location and extent of such offsite wetlands shall be determined by using the first of the following documents or procedures pertaining to such wetlands at the time of development:
(1) Site-specific delineation;
(2) Wetlands identified in watershed plans or ADID studies. If such plans are not available, then;
(3) Wetlands identified in interim watershed plans. If such plans are not available, then;
(4) Wetlands identified on NRCS wetlands inventory maps. If such maps are not available, then;
(5) Wetlands identified on the United States Fish and Wildlife Service National Wetlands Inventory maps.
(D) Final FQI assessments made before June 1 or after October 15, unless allowed at the discretion of the Administrator, shall be considered to be preliminary. Buffer requirements shall be based upon such assessments.
(E) All wetland mitigation required under a COE Section 404 permit for wetland disturbances in the village, shall be provided for. All wetland mitigation required under this subchapter for wetland impacts in the village shall be provided for in the same watershed where the wetland disturbances occurred.
(Ord. 2019-03, passed 4-15-2019)
Preserved wetlands shall be protected during development such that an FQI calculated upon completion of the project or two years after the commencement of development, whichever is later, will not be more than two points less than the FQI originally calculated. The developer shall mitigate for any wetland not so preserved at the ratio required for in the FQI originally calculated.
(Ord. 2019-03, passed 4-15-2019)
The requirements of this section are not applicable to wetlands or waters of the U.S. that, in either case, are below the threshold-size limitations for mitigation requirements under the COE 404 permit program.
(A) Buffers shall be identified on development plans for all areas defined as waters of the U.S. Buffer areas are divided into two types: linear buffers and water body buffers.
(1) Buffer areas, including the protected waters of the U.S., shall be shown to be within appropriate easements on all new plats. Additionally, the maintenance requirements for the buffer shall be noted on the plat or included as a covenant running with the land in any deed conveying any portion of a buffer area.
(2) Buffer widths required as a part of a COE permit supersede the widths required in this section, unless the width required herein is greater. If a COE permit is obtained to permanently fill a portion of a wetland and no buffer is required, the buffer width required by this subchapter immediately adjacent to the area of impact does not apply. IMMEDIATELY ADJACENT refers to the area within 15 feet of the area of impact. In no case shall additional wetland area be filled to provide buffer required by this subchapter.
(3) Jurisdictional waters of the U.S. or wetlands may not constitute a buffer. Buffer widths are to be 25 feet unless otherwise determined using the criteria specified below. Buffer width averaging is acceptable at the discretion of the Administrator. When using buffer width averaging, the width may not be more than 20% less, at the narrowest point, than the specified width. The buffer width may never be less than 15 feet, except in the case of waters of the U.S. or wetlands with a calculated FQI of less than seven, where the buffer at its narrowest point may not be less than 12 feet in width.
(a) Linear buffers shall be designated along waters of the U.S. and wetlands associated with water courses, i.e., swales, creeks, streams, rivers, and the like. Refer to division (A)(3)(b) below in cases where wetlands are adjacent to and not part of the main channel, i.e., floodplain wetland, backwater slough, oxbow, bordering wetland complex.
1. When the lineal waters of the U.S. have a drainage area greater than 640 acres, measured at the downstream property line, or is designated as ADID because of high habitat value or an adjacent wetland has a calculated FQI greater than 16, the buffer shall be 50 feet.
2. When the lineal waters of the U.S. have a drainage area less than 640 acres, measured at the downstream property line, the buffer width shall be determined utilizing the formula,
X = (A*0.0547)+ 15
Where X equals the buffer width in feet, and A equals the drainage area in acres.
The width calculated by this formula shall be rounded up to the nearest multiple of five.
3. If protective measures are installed along the perimeter of a buffer, the width may be reduced by up to 10% immediately adjacent to the protective measure. The reduction in width that may be applied due to installation of protective measures may not be applied where buffer width averaging has been used and the buffer would be more than 20% less than originally specified. Protective measures may consist of fencing, sediment basins, biological filter strips or other methods approved by the Administrator.
4. If lineal waters of the U.S. are completely or partially relocated, the newly created portion must be constructed in a manner that will allow naturalizing to occur; for example, meandering, pools, riffles and the like. Additionally, all disturbed areas must be replanted for stability with native vegetation where appropriate, appropriately managed and maintained and protected by an appropriately-sized buffer.
(b) Water body buffers shall encompass non-linear bodies of water meeting the definition of the waters of the U.S., including wetlands.
1. If protective measures are installed along the perimeter of a buffer, the width may be reduced by up to 10% immediately adjacent to the protective measure. The reduction in width that may be applied due to installation of protective measures may not be applied where buffer width averaging has been used and the buffer would be more than 20% less than originally specified. Protective measures may consist of fencing, sediment basins, biological filter strips or other methods approved by the Administrator.
2. For all non-lineal water bodies or waters of the U.S. designated as ADID or wetlands with an FQI greater than 16, a minimum buffer width must be established in accordance with Table 1.
3. For non-ADID wetlands with an FQI of 7 to 16, a minimum buffer width must be established in accordance with Table 2.
4. For non-ADID wetlands with an FQI of less than 7, a minimum buffer width must be established in accordance with Table 3.
(B) Buffers shall be replanted or reseeded using appropriate predominately-native, deep-rooted vegetation, appropriately managed and maintained following disturbance.
(C) The buffer area for all lineal and non-lineal waters of the U.S., except wetlands, shall extend from the jurisdictional limits of the waters of the U.S. ordinary high water mark. The buffer area for wetlands shall extend from the edge of the approved delineated wetland boundary. A site may contain a buffer that originates from a waters of the U.S. or wetland located on another property.
(D) Constructed stormwater management features shall not require a buffer and may constitute as a buffer. The total width of the buffer required may not be reduced by the installation of a stormwater management facility unless the facility can be considered a protective measure. If the facility can be considered to be a protective measure, then the width of the buffer may be reduced as specified in this subchapter.
(E) If a buffer area is disturbed by permitted activities during construction, the buffer strip shall be stabilized in accordance with this subchapter.
(F) Access through buffer areas shall be allowed when necessary for maintenance purposes only. Unless otherwise dedicated for a public purpose, buffer areas shall remain private property and are not generally accessible to the public.
(G) Unrestrained stormwater that has not passed through a site runoff storage facility shall discharge through an area or structure meeting the definition of best management practices or buffer before entering the jurisdictional waters of the U.S. or a wetland.
(1) Once established, all buffer areas shall be maintained free from development, except as described below:
(a) A buffer area may be used for passive recreation (e.g., bird watching, walking, jogging, bicycling, horseback riding and picnicking), and it may contain pedestrian, bicycle or equestrian trails, provided that the created path is no wider than ten feet. To help prevent erosion, paths leading to a wetland must be winding.
(b) Utility maintenance, maintenance of drainage facilities and drainage easements shall be allowed, provided the maintenance activity meets all other federal, state and local regulations.
(c) Anchoring and placement of boat docks and piers shall be allowed, provided the structure meets all other federal, state and local regulations.
TABLE 1 – HIGH QUALITY WETLANDS – FQI > 16 | |||
Buffer Ratio | Wetland Area (Acres) | Buffer Area (Acres) | Buffer Width (Feet) |
0.5 | 0.25 | 0.125 | 15.0 |
0.5 | 0.5 | 0.25 | 20.0 |
0.5 | 0.75 | 0.375 | 25.0 |
0.5 | 1.0 | 0.5 | 30.0 |
0.5 | 1.25 | 0.625 | 30.0 |
0.5 | 1.5 | 0.75 | 35.0 |
0.5 | 1.75 | 0.875 | 35.0 |
0.5 | 2.0 | 1.0 | 40.0 |
0.5 | 2.25 | 1.125 | 40.0 |
0.5 | 2.5 | 1.25 | 45.0 |
0.5 | 2.75 | 1.375 | 45.0 |
0.5 | 3.0 | 1.5 | 50.0 |
0.5 | 3.25 | 1.625 | 50.0 |
0.5 | 3.5 | 1.75 | 50.0 |
0.5 | 3.75 | 1.875 | 50.0 |
0.5 | 4.0 | 2.0 | 50.0 |
0.5 | 4.25 | 2.125 | 50.0 |
0.5 | 4.5 | 2.25 | 50.0 |
0.5 | 4.75 | 2.375 | 50.0 |
0.5 | 5.0 or more | 2.5 | 50.0 |
Buffer ratio = % of total wetland area
Wetland Area = Total onsite and offsite area of the wetland
Buffer Area = Wetland Area x Buffer Ratio
Buffer Width = 
TABLE 2 – MEDIUM QUALITY WETLANDS – 7 < FQI < 16 | |||
Buffer Ratio | Wetland Area (Acres) | Buffer Area (Acres) | Buffer Width (Feet) |
0.4 | 0.25 | 0.1 | 15.0 |
0.4 | 0.5 | 0.2 | 15.0 |
0.4 | 0.75 | 0.3 | 20.0 |
0.4 | 1.0 | 0.4 | 25.0 |
0.4 | 1.25 | 0.5 | 25.0 |
0.4 | 1.5 | 0.6 | 30.0 |
0.4 | 1.75 | 0.7 | 30.0 |
0.4 | 2.0 | 0.8 | 30.0 |
0.4 | 2.25 | 0.9 | 35.0 |
0.4 | 2.5 | 1.0 | 35.0 |
0.4 | 2.75 | 1.1 | 35.0 |
0.4 | 3.0 | 1.2 | 40.0 |
0.4 | 3.25 | 1.3 | 40.0 |
0.4 | 3.5 | 1.4 | 40.0 |
0.4 | 3.75 | 1.5 | 45.0 |
0.4 | 4.0 | 1.6 | 45.0 |
0.4 | 4.25 | 1.7 | 45.0 |
0.4 | 4.5 | 1.8 | 45.0 |
0.4 | 4.75 | 1.9 | 50.0 |
0.4 | 5.0 or more | 2.0 | 50.0 |
Buffer ratio = % of total wetland area
Wetland Area = Total onsite and offsite area of the wetland
Buffer Area = Wetland Area x Buffer Ratio
Buffer Width =
TABLE 3 – LOW QUALITY WETLANDS – FQI < 7 | |||
Buffer Ratio | Wetland Area (Acres) | Buffer Area (Acres) | Buffer Width (Feet) |
0.3 | 0.25 | 0.075 | 15.0 |
0.3 | 0.5 | 0.15 | 15.0 |
0.3 | 0.75 | 0.225 | 15.0 |
0.3 | 1.0 | 0.3 | 20.0 |
0.3 | 1.25 | 0.375 | 20.0 |
0.3 | 1.5 | 0.45 | 20.0 |
0.3 | 1.75 | 0.525 | 25.0 |
0.3 | 2.0 | 0.6 | 25.0 |
0.3 | 2.25 | 0.675 | 25.0 |
0.3 | 2.5 | 0.75 | 25.0 |
0.3 | 2.75 | 0.825 | 30.0 |
0.3 | 3.0 | 0.9 | 30.0 |
0.3 | 3.25 | 0.975 | 30.0 |
0.3 | 3.5 | 1.05 | 30.0 |
0.3 | 3.75 | 1.125 | 35.0 |
0.3 | 4.0 | 1.2 | 35.0 |
0.3 | 4.25 | 1.275 | 35.0 |
0.3 | 4.5 | 1.35 | 35.0 |
0.3 | 4.75 | 1.425 | 35.0 |
0.3 | 5.0 | 1.5 | 35.0 |
Buffer ratio = % of total wetland area
Wetland Area = Total onsite and offsite area of the wetland
Buffer Area = Wetland Area x Buffer Ratio
Buffer Width = 
(Ord. 2019-03, passed 4-15-2019)
(A) Wetlands identified as having a Flora Quality Index (FQI) greater than or equal to 25 shall not be filled or dredged as part of any development. The FQI shall be based solely on the wetland vegetation. Buffers and adjacent plant communities shall not be included in the calculation.
(B) If the application of this section would:
(1) Have the effect of depriving the owner of all economically beneficial or productive use of the land; or
(2) Make the construction or installation of an essential public improvement by a public entity impossible or highly impractical;
the applicant may apply for a variance from the requirements of this subchapter. If such variance is granted, mitigation for the wetland impact allowed shall be made pursuant to this subchapter.
(Ord. 2019-03, passed 4-15-2019)
All mitigable wetland impacts shall be mitigated as required under the COE 404 permit program.
(A) For all mitigable wetland impacts:
(1) Mitigation may be made within a wetland mitigation facility;
(2) Mitigation may be made by the purchase of credits from a wetland mitigation bank; and
(3) Mitigation may be made by the payment of a fee-in-lieu of mitigation pursuant to this subchapter.
(B) Wetland impacts upon wetlands with an FQI of 7 or more, but less than 16, shall be mitigated at a ratio of 2:1.
(C) Wetland impacts upon wetlands with an FQI of 16 or more, but less than 25, shall be mitigated at a ratio of 3:1.
(D) Wetland impacts upon wetlands with an FQI of more than 25 shall be mitigated at a minimum ratio of 10:1, plus one half for each point by which the FQI exceeds 25, rounded up to the nearest whole number.
(E) Wetland impacts upon wetlands that are inhabited by a threatened or endangered species shall be mitigated at a ratio of 3:1.
(F) Mitigation for wetland impacts upon more than one wetland within a site shall meet the standards applicable to each individual wetland that is impacted.
(G) FQI assessments made before June 1 or after October 15 shall be considered to be preliminary. Mitigation requirements based upon such a preliminary assessments shall not be considered to be final until a proper final FQI assessment is made, unless an FQI of at least 16 is applied to the mitigation. Preliminary FQI assessments that exceed 16 will require final FQI assessments.
(H) The applicant may propose an alternative mitigation plan combining wetland creation, purchase of credits from a wetland mitigation bank, payment of a fee-in-lieu of wetland mitigation and/or enhancing existing wetlands, either onsite or offsite. The Administrator shall determine if a proposed alternative mitigation plan meets the requirements of this section and his or her decision shall be final.
(Ord. 2019-03, passed 4-15-2019)
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