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The type, quality and significance of the ecological and cultural benefits provided by wetland resources, such as: flood storage, water quality protection, groundwater recharge and discharge, shoreline protection, fish and wildlife habitat, floral diversity, aesthetics, recreation and education. Sec Section of the McFarland Municipal Code is hereby repealed and recreated to read as follows: "Sec. This Ordinance applies to land development activities which meet the applicability criteria specified in this section.
The Ordinance also applies to land development activities that are smaller than the minimum applicability criteria if such activities are part of a larger common plan of development or sale that meets any of the following applicability criteria, even through multiple, separate and distinct land development activities may take place at different times on different schedules: 1 Residential land development with a gross aggregate area of five acres or more; 2 Residential land development with a gross aggregate area of at least three acres, but less than five acres, if there are at least 1.
Public Safety Guidance for Urban Stormwater Facilities provides guidance for reducing risks from safety hazards at facilities managing urban stormwater. People. Public Safety Guidance For Urban Stormwater Facilities. Free Download Ebook Public Safety Guidance For Urban Stormwater Facilities at.
This Ordinance applies to land development activities within the boundaries of the Village. This Ordinance also applies to all lands located within the extraterritorial plat approval jurisdiction of the Village, even if plat approval or land division is not involved. Unless prior authorization is given by the Director of Public Works, the following methods shall be used in meeting the requirements of this Ordinance; a Water Quality Components.
The following methods shall be used in designing components of stormwater structures needed to meet the water quality standards of this Ordinance: 1 Practices shall be designed in accordance with the methods set forth in the latest edition of the Wisconsin Storm Water Manual, Part 2: Technical Design Guidelines for Storm Water BMP's as published and amended by the State of Wisconsin Department of Natural Resources.
The following methods shall be used in designing components of stormwater structures needed to meet the water quantity standards of this Ordinance: 1 Peak flow reducing components and all other stormwater management structures shall be designed in accordance with standard engineering practice. Unless otherwise provided for in this Ordinance, all land development activities subject to this Ordinance shall establish on-site management practices to control the peak flow rates of stormwater discharged from the site.
Infiltration of stormwater runoff from driveways, sidewalks, rooftops, and landscaped areas shall be incorporated to the maximum extent practical to provide volume control in addition to control of peak flows. On-site management practices shall be used to meet the following minimum performance standards: 1 The peak flow discharge rates of stormwater runoff from the development shall not exceed those calculated for the series of design storms specified in Section a 2 and pre-development conditions specified in Section a 3.
Discharge velocities must be non-erosive to discharge locations, outfall channels, and receiving streams. The Natural Resource Conservation Service TR Method shall be used to calculate peak flow discharge rates and runoff volumes for the pre-development condition, for the McFarland area. Where such changes are proposed, the impact of the proposal on wetland functional values shall be assessed using a methodology acceptable to the Village Engineer and in conformity with Wis. Code Chap.
Significant degradation of wetland functional values shall be avoided. Unless otherwise provided for in this Ordinance, all land development activities subject to this Ordinance shall establish on-site management practices to control the quality of stormwater discharged from the site. To achieve this level of control, stormwater practices shall be designed to accommodate, at a minimum, the runoff volume resulting from 1.
Where such discharges are proposed, the impact of the proposed discharge on wetland functional values shall be assessed using a method acceptable to the Village Engineer and in conformity with Wis. At a minimum, stormwater discharges shall be pre-treated prior to discharge to wetlands. Significant degradation of wetland functional values due to stormwater pollutant loads shall be avoided.
Stormwater shall not be injected underground through excavations or openings that would violate Wis. A feet from a well serving a private water system or a transient, non community public water system; B 1, feet from a well serving a municipal public water system, an other than municipal water system, or a non-transient non-community public water system; C The boundary of a recharge area to a wellhead identified in a wellhead area protection plan.
The Director of Public Works may establish stormwater management requirements either more stringent or less stringent than those set forth in Sections a and b , provided that at least one of the following conditions applies. C The facility has a legally obligated entity responsible for its long-term operation and maintenance. Where the site meets the size criteria of Section a 5 , or the Director of Public Works otherwise determines that it would be inappropriate to require a site to meet the minimum stormwater management requirements on site pursuant to Section c , the applicant shall pay a fee to the Village, to be used by the Village exclusively for the cost of land, engineering design, construction and maintenance of stormwater management practices.
The following considerations shall be observed in managing stormwater runoff 1 Natural topography and land cover features such as natural swales, natural depressions, native soil infiltrating capacity, and natural groundwater recharge areas shall be preserved and used, to the extent possible, to meet the requirements of this section. No landowner or operator may undertake a land development activity subject to this Ordinance without receiving a permit from the Director of Public Works prior to commencing the proposed activity.
Unless specifically excluded by this Ordinance, any land owner or operator desiring a permit shall submit to the Director of Public Works a permit application made on a form provided by the Director of Public Works for that purpose. The Director of Public Works shall review any permit application that is submitted with a stormwater management plan, maintenance agreement and the required fee. The following approval procedure shall be used: 1 Within five business days, the Director of Public Works shall determine whether the applicant has submitted a complete permit application, including all items required by Section b 1.
If the materials are incomplete, the Director of Public Works shall inform the applicant regarding what additional materials are required.
Holes 50 mm diameter are drilled in the metal pipe such that it acts as a riser. Given that there are 20 different SCM groups and a much larger number of individual design variations or practices within each group, it is difficult to au- thoritatively define the specific performance or effectiveness of SCMs. A design which is frequently used in Ontario incorporates a perforated riser pipe surrounded by a corrugated metal pipe standing on its end. But while hardening and enlarging natural channels is a cost-effective solution to erosion and flooding, the modified channel increases downstream peak flows and it does not provide habitat to support a healthy aquatic ecosystem. Most ponds which discharge directly to a stream will be in close proximity to the receiving waters the pond will likely be located in the lowest section of the tableland adjacent to the receiving waters.
The Director of Public Works shall base the decision on requirements set forth in Sections , and of the McFarland Municipal Code. All permits issued under this Ordinance shall be subject to the following conditions, and holders of permits issued under this Ordinance shall be deemed to have accepted these conditions.
The Director of Public Works may suspend or revoke a permit for violation of a permit condition, following written notification of the permittee. An action by the Director of Public Works to suspend or revoke this permit may be appealed in accordance with Section of this Ordinance.
If required as a special condition, the permit holder shall make additional notification according to a schedule set forth by the Director of Public Works so that practice installations can be inspected during construction. Completed stormwater management practices must pass a final inspection to determine if they are in accordance with the approved stormwater management plan and Ordinance.
The administering authority shall notify the permit holder in writing of any changes required in such practices to bring them into compliance with the conditions of this permit. The Director of Public Works may require that the proposed modifications be submitted for approval prior to incorporation into the stormwater management plan and execution. Permits issued under this section shall be valid from the date if issuance through the date the Director of Public Works notifies the permit holder that all stormwater management practices have passed the required final inspection.
If work is not commenced within days, the permit shall expire. The Director of Public Works may attach additional conditions before reissuing a permit. On-line quality ponds can only be approved if issues of aquatic habitat can be resolved. An on-line facility can only be proposed in the context of a subwatershed plan. In all development submissions, there should be a concerted effort to preserve the existing watercourse in its natural state. In cases where watercourse alterations are deemed necessary, the alterations should be designed using natural channel design techniques.
Alterations to watercourses will, in most cases, require authorization under Section 35 2 of the federal Fisheries Act. The location of end-of-pipe stormwater management facilities is a contentious issue since the use of tableland reduces the overall area available for development.
In an effort to minimize the loss of developable land, some municipalities allow the use of parkland dedication for SWMPs which offer recreational opportunities such as trails and playing fields. By offsetting the potential loss of land area available for development, the stormwater management facility, designed in whole or in part as usable parkland, may be considered acceptable. An extensive review of cold climate design considerations was undertaken by the Centre for Watershed Protection Much of the information contained in the document is based on the results of a survey conducted among practitioners operating in cold climates.
The major recommendations relating to cold climate design include:. However, the recommendations regarding storage volume increases and designs to limit problems due to freezing warrant consideration and are discussed further below. A number of factors combine to make water quality treatment of winter runoff more difficult. Typically, a finer range of particles is washed off in winter due to the lower flow rates associated with melt events. Finer particles require longer to settle and so the relative removal efficiency may be expected to drop in winter. In many situations, ice formation will reduce the effective volume of a permanent pool causing more frequent overflows or reduced event capture.
Ice formation may eliminate a permanent pool entirely so that only active storage is available for treatment. The Centre for Watershed Protection CWP design supplement suggests increasing the water quality volume provided in order to accommodate multi-day snowmelt events. This is not necessary for the volumes recommended in Table 3.
The latter measure ensures that some treatment will continue to occur when the pool is completely frozen over. In most cases where water quality and erosion control storage are provided in the same facility, the minimum active storage volume for water quality will be met without the need for additional volume. The former measure may be particularly important in more northern portions of the province where temperature regimes are such that ice cover may persist into the spring when runoff rates and contaminant washoff are more of a concern than they typically are during the winter.
In these areas of the province, it is recommended that the permanent pool volume be increased by an amount equal to the expected volume of the ice cover. Work done at a pond in Kingston, Ontario, indicated that a coefficient value of 15 produced results close to measured values Marsalek, The pond operated with a constant subsurface inflow, which tended to limit the build-up of ice.
In general, it is expected that most ponds will be small enough and will receive sufficient inflow to behave more like a river in terms of ice build-up than a lake. Where possible, however, the designer should consult with the local municipality or conservation authority concerning local knowledge on ice depths. A number of the recommendations of the Centre for Watershed Protection study regarding inlets and outlets should also be considered:. Specific recommendations for cold climate design are provided in the subsequent sections describing each SWMP.
There are a number of reports which indicate that urban development end-of-pipe SWM facilities increase the temperature of water before it is discharged to the receiving waters Beland, , Galli, , Schueler, Galli found that there is an increase in water temperature with all types of urban development SWMPs. These reports also stress, however, that an increase in water temperature is inevitable if an area is developed i. This observation is based on current development practices. It is anticipated that employing the integrated approach to stormwater management described in Section 2.
Literature values of temperature increases with different types of end-of-pipe stormwater management facilities have been recorded Galli, and are provided in Table 4. Wet ponds and wetlands can compound the temperature increase due to urbanization by maintaining water in the facility between storms and allowing it to acclimate to the air temperature.
There are several techniques that can be used to reduce thermal impacts. The configuration of a pond will affect its temperature. The length-to-width ratio should be maximized to prevent the occurrence of large open areas of water which cannot be shaded by riparian vegetation. Planting in the shoreline fringe and flood fringe zones of a wet pond help to shade the pond and minimize temperature increases during inter-event periods.
The planting strategy should incorporate designs which shade open water areas when the vegetation reaches maturity.
There are temperature benefits from a bottom-draw facility, although this is dependent on the size of the permanent pool and the release depth. There is a minimal difference in water temperature within the top metre of a permanent pool. Lower temperatures in the order of several degrees Celsius occur several metres below the permanent pool surface.
Ponds with permanent pool depths greater than 3 metres, however, are likely to become thermally stratified during the summer months. The water at depth can become anoxic, and there is a potential for metals and nutrients to be remobilized. Although the oxygen deprivation can be solved by re-aeration at the outlet e. However, this may reduce sedimentation and resuspend sediment collected at the pond bottom.
Treatment of water, by routing the discharge through a subsurface trench filled with clear stone, has also been suggested to reduce temperature. As the water flows through the trench, heat is transferred to the stone. It is purely a conveyance system which does not rely on infiltration; however, there is relatively little knowledge with respect to the success of these systems. The dimensions of the system depend on the intended range of release rates, and the proximity of the pond to the watercourse.
The length of the trench should be maximized to increase the opportunity for heat transfer. The cross-sectional area of the trench should be sized based on the design conveyance flow which does not necessarily have to match the design release rate from the pond especially if the pond will accommodate the runoff from relatively large storms; i.