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Environmental Policies Environmental Goal Preserve, protect, and restore the natural resources and environment of Dexter Township and the region through a comprehensive approach to water quality management and preservation of our natural features.

Environmental Objective #1: Identify and inventory Dexter Township’s natural features and environmentally sensitive areas.

Strategies

1.1 Actively utilize and maintain available GIS mapping data from Washtenaw County and other agencies, and continually update Dexter Township’s maps of natural features and environmentally sensitive areas as newer and more accurate data becomes available. Such data should include topography, soils, slopes, water bodies, floodplains, sub-watersheds, sub-basins, groundwater recharge areas, wetlands, woodlands, plant and flora quality, and land use.

1.2 Use information from the Huron River Watershed Council (such as the bioreserve project) and other agencies to prioritize the quality of natural features and environmentally sensitive areas based on their size, hydrology, topography, connectivity, biodiversity, ability to sustain a viable wildlife habitat, and other related factors.

1.3 Educate the public (including Dexter Township officials and appointees) by posting and updating maps of Dexter Township’s natural features and environmentally sensitive areas at Dexter Township Hall and on Dexter Township’s website.

Environmental Objective #2: In accordance with the results of the 2007 Dexter Township Community Survey (where the following were rated as a High Priority accordingly by respondents: “Groundwater quality” (81.8%), “Surface water quality (lakes, rivers, etc.) and storm water runoff” (78.2%), and “Protection of wetlands” (67.7%)), protect and enhance the quality of water resources in Dexter Township through a comprehensive approach of education, planning, regulation, and enforcement.

Strategies

2.1 Educate the public (including Dexter Township officials and appointees) on the importance of protecting water quality, how local land uses affect water quality, and strategies that can be used to protect and improve water quality. Education materials should include the environmental impacts of impervious surfaces and phosphorus sources.

2.2 Where necessary, require proposed development to evaluate the capacity of the groundwater to supply quality water.

2.3 Where appropriate, require proposed developments to conduct a hydrogeological evaluation to determine the location and boundaries of groundwater recharge areas, and determine whether the proposed development will impact the groundwater recharge areas.

2.4 Adopt and actively enforce Township storm water management standards for development and redevelopment in or near environmentally sensitive areas through the use of best management practices (BMPs).

2.5 Consider the adoption of phosphorus and pesticide regulations that will prohibit excessive application and limit the amount of phosphorus and toxins that enter our lakes, rivers, streams, ponds, and wetlands.

2.6 Where a portion of land is characterized by floodplains, discourage development within the floodplain.

2.7 Consider the adoption of a wetland protection ordinance if other strategies are inadequate in preserving and protecting the quantity and quality of Dexter Township’s wetlands.

2.8 Consider the adoption of an overlay district to protect areas that are relatively more environmentally sensitive to water pollution (including steep slopes, floodplains, groundwater recharge areas, wetlands, bioreserve areas, and areas near water bodies). At the same time, consider increasing the allowable densities outside of the overlay district as a means of partially or wholly offsetting the development that would have otherwise been permitted inside of the overlay district.

2.9 Where appropriate, encourage a “Green Streets” strategy which provides for roadside on-site storm water treatment of typical rain events via low, dense vegetation.

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Environmental Objective #3: Preserve and enhance the quality of wildlife habitat and biodiversity in Dexter Township through a comprehensive approach of education, planning, regulation, and enforcement.

Strategies

3.1 Educate the public (including Dexter Township officials and appointees) on the importance of protecting wildlife habitat and biodiversity, how local land uses affect them, and strategies that can be used to protect and improve them.

Environmental Objective #4: Protect the visual environment and rural character of Dexter Township through management of outdoor lighting and its impact upon traffic safety, adjacent and nearby land uses, and the night sky.

Strategies

4.1 Educate the public (including Dexter Township officials and appointees) on the importance of preserving the night sky, how local land uses affect the night sky, and strategies that can be used to light an area in a way that maximizes security and safety while also minimizing glare, sky glow, light trespass, energy waste, and financial waste.

4.2 Enforce the outdoor lighting standards in the Dexter Township Zoning Ordinance.

4.3 When the outdoor lighting standards in the Dexter Township Zoning Ordinance are deficient or inadequate, prepare a separate ordinance or amend the Zoning Ordinance to appropriately regulate outdoor lighting in a way that maximizes security and safety while also minimizing glare, sky glow, light trespass, energy waste, and financial waste.

Environmental Objective #5: Make land use decisions with the intent of protecting environmentally sensitive areas and preventing conflicts between land uses and environmentally sensitive areas.

Strategies

5.1 Verify compliance with local, state, and federal environmental regulations when reviewing all land use proposals.

5.2 Minimize the impact on natural features and environmentally sensitive areas when reviewing all land use proposals.

5.3 Encourage maximum retention and preservation of environmentally sensitive areas during site plan design, review, and approval processes.

5.4 Enforce all applicable Township Ordinance regulations that protect environmentally sensitive areas.

5.5 In accordance with the results of the 2007 Dexter Township Community Survey (where the following were rated as a High Priority accordingly by respondents: “Groundwater quality” (81.8%), “Surface water quality (lakes, rivers, etc.) and storm water runoff” (78.2%), “Protection of woodlands and large trees” (72.7%), “Preservation of natural undeveloped land” (69.2%), and “Protection of wetlands” (67.7%)), consider applying for funding for natural area preserves and PDR agreements where appropriate and where such agreements will further this objective.

5.6 Although the results of the 2007 Dexter Township Community Survey (where a minority of respondents stated that they would support additional taxes for “Preservation of natural undeveloped land” (28.7%), “Protection of wetlands” (23.4%), Surface water quality and storm water runoff” (23.6%), “Groundwater quality” (23.7%), and “Protection of woodlands and large trees” (22.5%)) suggest little support for a new millage to fund additional environmental protection, consider such millages if there is a demonstrated demand for them from the electorate.

5.7 Consider adoption of a Transfer of Development Rights (TDR) ordinance that would allow increased development in areas that Dexter Township has designated for development in return for preservation of places it wants to protect, such as environmentally sensitive areas. A TDR program shall only be considered under the following circumstances:

1. The “sending” areas (i.e., the land where development rights are transferred from) and “receiving” areas (i.e., the land where development rights are transferred to) are defined and approved by Dexter Township; and

2. The number of units approved by Dexter Township does not not exceed the number of units that would have otherwise been approved by Dexter Township without the TDR; and

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3. The “receiving” area is serviced by adequate public infrastructure prior to approval of any increase in density.

When invited, participate with other municipalities in the region to study and consider a regional TDR program, even if Dexter Township ultimately opts not to participate in a regional TDR program.

Environmental Objective #6: Oppose sanitary landfills, hazardous waste sites, nuclear waste storage of any type or classification, and similarly hazardous uses within Dexter Township.

Strategies

6.1 Maintain Township policy, which emphasizes the incompatibility of landfills, hazardous waste sites, and nuclear storage facilities of any type or classification within Dexter Township.

6.2 Know the procedure by which landfills, hazardous waste sites, and nuclear storage facilities are sited.

Environmental Objective #7: In accordance with the results of the 2007 Dexter Township Community Survey (where the 72.7% of respondents rated “Protection of woodlands and large trees” as a High Priority), preserve and protect the woodland areas in Dexter Township through a comprehensive approach of education, planning, regulation, and enforcement.

Strategies

7.1 Educate the public (including Dexter Township officials and appointees) on the importance of preserving woodlands, how local land uses affect woodlands, and strategies that can be used to protect woodlands.

7.2 Minimize the impact on woodlands and large trees when reviewing all land use proposals.

7.3 Encourage maximum retention and preservation of woodlands and large trees during site plan design, review, and approval processes.

DEFINITIONS

Wetland: Land characterized by the presence of water at a frequency and duration sufficient to

support and that, under normal circumstances, supports wetland vegetation or aquatic life, and is

commonly referred to as a bog, swamp, or marsh. If state regulated it is not a wetland for

purposes of this ordinance,

Surface Waterbody: Any area that permanentlynormally has water flowing or standing above

ground to the extent that evidence of an ordinary high-water mark is established and is not

confined to one lot. Lakes, ponds, whether natural or artificial, rivers, and streams, and other

watercources and waters characterizeed by this definition shall be considered as surface water

bodies.

Watercourse: Any and all rivers, streams, creeks, tributaries, lakes, ponds, wetlands, and other types of natural or man-made structures that channel, contain;, or retain water. Vegetative Filter Strip: Treats stormwater pollutants with that stormwater sheet flowing through healthy vegetation such as such as turf grass, or swales, and/or meadow, and/or woods, with a maintenance plan and protected by site or plot plan requirements to prevent neglect, adverse alteration, or removal. Its intent is to decrease velocity, permit natural infiltration, encourage passive storage, allow sediment particles to settle, and remove pollutants. 17.40 Deals with stormwater and has been incorporated into 17.45 below 17.45 Stormwater Management

(A) General Provisions: The following standards shall apply for when standards for impervious coverage are exceeded in order to protect existing surface waterbodies and wetlands from negative impacts of polluted or excessive stormwater.

1 Direct Discharge: Except as authorized by the State of Michigan’s ground water discharge permits, dDirect discharge thru a vegetative filter strip into a wetland is only permitted if the strip is at least 10 feet deep or only into a surface waterbody if the strip is at least 30 feet deep or wetland . Absent the required Vegetative Filter Strip, direct discharge to a surface waterbody shall be prohibited unless it is first intercepted by a filtering device approved by the Township Engineer sump or French drain .

2. Construction: Stormwater management facilities shall be installed as soon as possible during construction.

3. Impacts: Any proposed impacts to surface waterbodies shall adhere to applicable regulations of the MDEQ.

4. On-site Detention: All sites shall retain stormwater on site or shall detain it to allow discharge without a negative impact on adjacent properties, streets, or waterbodies. or wetlands. 5. Natural Drainage Patterns: NO CHANGE 6. Adverse Impacts: NO CHANGE 7. Level of Service: NO CHANGE 8. Increased Volume: Any increase volume of runoff shall not create adverse impacts to adjacent properties, streets, or waterbodies. or wetlands. Delete Swales - it was added to Vegetative Filter Strip:

(B) Plot Plans: Absent total stormwater on-site retention, in addition to the

general……………… Change: impervious coverage to 45%, and

Change: within thirty-five to thirtythirty (30) feet of a surface waterbody No change to (B.1), a., b., c., e., and f. Remove: swales from d. (part of vegetative filter strip) No other suggested changes to 17.45

Dexter Township Planning & Zoning 6880 Dexter-Pinckney Road

Dexter, MI 48130 Telephone: 734-426-3767

Fax: 734-426-3833 dpz@DexterTownship.org

www.DexterTownship.org

_______________________________________________________________________________________

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Zach Michels Director

Christina McEmber Ordinance Officer

Nick Schrader Planning & Zoning Intern

“ A C o m m u n i t y F o r A l l S e a s o n s ”

DATE: June 19, 2018 TO: Planning Commission FROM: Zach Michels, Director of Planning & Zoning RE: Zoning Ordinance Review- Water Quality & Quantity

Zoning Ordinance – Water Quality & Quantity

The Planning Commission forwarded a draft zoning ordinance to the Township Board on August 22, 2017, with a

favorable recommendation. The Township Board has been reviewing the draft document since that time.

In early 2018, the Township Board has decided to remand several sections of the draft document back to the Planning

Commission for further attention. The Planning commission has reviewed and provided guidance on those other sections,

starting in March 2018, but it never discussed or took any action on §17.40: Water Quality and Quantity.

This report provides basic information about the applicable standards in the current Zoning ordinances, the standards that

were forwarded as part of the draft zoning ordinance, and any changes that the Township Board has made. It also

includes attachments of the actual text and other useful information.

Water Quality and Quantity

The current Zoning Ordinance includes some standards related to water quality. These standards are included in Article

24: Environmental Standards. However, these standards are scattered in several sections of that Article and do not always

provide clear guidance for applicants or staff, nor do they do a particularly good job of protecting water quality in all

conditions.

Before beginning work on the new zoning ordinance, planning staff reviewed and consulted the adopted Master Plan.

There was tremendous support from the community for protection of wetlands and water. Of the survey responses, 78.2%

stated that protection surface water quality of lakes and rivers was a high priority; 81.8% stated that protection of

groundwater quality was a high priority; and 42.6% stated that storm water runoff was a high priority. The groundwater

and surface water quality received the most support of all of the 16 items included in the community survey.

Water Quality & Quantity Reveiw June 19, 2018

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The above responses make sense, as all the potable drinking water within the Township is supplied by on-site or

community wells and a large percentage of the population lives on or makes use of the waterbodies. Poor water quality

could also have a negative impact on the use and enjoyment of the Township’s waterbodies and the value of properties in

the Township.

§17.40:Water Quality and Quantity was added to the draft zoning ordinance to address gaps in the current Zoning

Ordinance language and the priorities identified in the adopted Master Plan. Many of these concerns are addressed in a

community’s engineering standards. Dexter Township, however, has not adopted engineering standards.

The Township Board voted “to send §17.30 and §17.40 to the Planning Commission for further review, and deliberation

in consideration of the memorandum submitted by Gajewski, and report back to the Township Board.”

The Planning Commission should prepare and provide a report back to the Township Board concerning this section.

The following materials are attached to this report for wetlands and water quality and quantity:

Article 24: Environmental Standards (current Zoning Ordinance);

§17.40: Water Quality and Quantity (compiled August 7, 2017, as forwarded to the Township Board);

Gajewski memorandi concerning wetlands and water quality and quantity.

Dexter Township Zoning Ordinance Article 24: Environmental Standards

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Article 24 ENVIRONMENTAL STANDARDS

Section 24.01: PURPOSE The purpose of this Article is to promote a healthy environment in Dexter Township as it relates to the Township's natural resources, sensitive ecosystems, the integrity of the Township's land, water, and air, and the quality of the Township's visual environment, including the management of outdoor lighting and its impact upon traffic safety, adjacent land uses and the night sky. All provisions of this Article apply to all structures and uses unless otherwise noted. Section 24.02: NATURAL RESOURCES A. Compliance with Local, County, State, and Federal Regulations: All land uses and construction activities shall

conform with the provisions of this Ordinance and all county, state and federal regulations including, but not limited to, the following: 1. Published surface water drainage standards of the Washtenaw County Road Commission and Washtenaw County

Drain Commissioner, except where not required by law and not determined to be applicable to the specific project during site plan review proceedings.

2. Applicable fire safety and emergency vehicle access requirements of the State Building Code, State Fire Marshall and Local Fire Code.

3. Soil erosion and sedimentation requirements of the Washtenaw County Drain Commissioner. 4. Requirements of the Michigan Department of Public Health and the Washtenaw County Health Department. 5. Michigan Department of Environmental Quality requirements for air or water quality protection, wetlands, stream

crossings, fills in or near water bodies or in flood plains, and for waste disposal. 6. All local, county, state and federal regulations related to loading/unloading, transport, storage, use and/or disposal of

hazardous substances. 7. Applicable rules and regulations of the Federal Communications Commission.

B. Discharges 1. No dust, fumes, or noxious, odorous matter shall be discernible at or beyond the property line except in the case of

agricultural operations complying with the Michigan Commission on Agriculture’s Generally Accepted Agricultural Management Practices. Any atmospheric discharge requiring a permit from the Michigan Department of Natural Resources or federal government shall have said permit(s) as a condition of approval for any use in this district. The escape of or emission of any gas which is injurious or destructive or explosive is prohibited.

2. It shall be unlawful to discharge at any point any materials in such a way or of such nature or temperature as can contaminate any surface waters, land or aquifers, or otherwise cause the emission of dangerous or objectionable elements, except in accord with standards approved by the Michigan Department of Natural Resources.

3. Radioactive emissions shall not exceed quantities or levels established as safe by state or federal regulations. C. Sensitive Lands

1. Where a portion of a parcel is characterized by wetlands, hydric soils, flood plains, or steep slopes, new development on the parcel shall only occur on those portions of the parcel void of such sensitive resources where reasonably feasible.

2. The Township shall not approve any land use which requires a county, state, or federal permit, until such permit has been obtained and satisfactory evidence has been submitted verifying the acquisition of the necessary permits, or satisfactory evidence has been submitted to the approving body verifying the acquisition of such permit is not necessary.

3. The Township may require mitigation measures be taken to replace those resources disturbed or destroyed by a land use, or to otherwise lessen the impact of a new land use upon natural resources and sensitive areas.

D. Clearing, Grading, and Filling: In order to protect soil resources, adjacent properties, public roads, public watercourses, and to provide for adequate drainage of surface water, the following rules shall apply to all construction activities requiring permits pursuant to this Ordinance. 1. Clearing of a Site: Stripping and removal of topsoil from the site is prohibited prior to the completion of all

approved site improvements and the seeding, sodding, and landscaping of all disturbed areas. “Disturbed areas,” as applied to this section, shall be interpreted to mean any area of a lot which is altered by grading or other construction activities and which area is not proposed to be paved or otherwise built upon.

2. Flow Restrictions: The final grade surface of ground areas surrounding a building or structure shall be designed and landscaped such that surface water flow away from the building or structure and is managed in a manner which avoids increased flow onto adjacent properties or public roads, the erosion or filling of a roadside ditch, the blockage of a public watercourse or the creation of standing water over a private sewage disposal drainage field.

3. Elevation Restrictions: Filling a parcel of land to an elevation above the established grade of adjacent developed land is prohibited without the expressed written approval of the County Drain Commissioner, and approval by the Planning Commission.

Dexter Township Zoning Ordinance Article 24: Environmental Standards

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Section 24.03: POTABLE WATER and SEWAGE DISPOSAL Any structure for human occupancy and used for dwelling, businesses, industrial, recreational, institutional, mercantile or storage purposes shall not be erected, altered, used or moved upon any premises after the effective date of this Ordinance unless said structure shall be provided with a potable water supply and waste water disposal system that ensures a safe and effective means of collection, treatment, and disposal of human, commercial, and industrial wastes. All on-site sewage disposal and potable water facilities shall be constructed and maintained in accordance with the requirements and standards of the Washtenaw County Environmental Health Department as well as those of other applicable local, county, state, or federal agencies.

Section 24.04: LIGHTING A. For the purposes of this Section, the following terms and phrases shall be defined as follows:

1. Cut Off Angle: An angle measured upward from nadir at the lowest point of the light source, beyond which no light, or only a limited amount of light, is permitted to penetrate. For example purposes, a cut off angle of ninety (90) degrees would create a horizontal plane at a height equal to the bottom of the light source, while a cut off angle of forty-five (45) degrees would extend from the ground directly below the light source, at nadir, to an angle midway between nadir and a cut off angle of ninety (90) degrees.

2. Light Source: The primary source of a lighting fixture from which light is emanated, such as a light bulb or similar source. 3. Lighting Fixture: All electrical, structural, and accessory parts of a device intended to cast light upon an outdoor area. 4. Nadir: An imaginary vertical line extending from ground level to the bottom of the light source.

B. No lighting shall in any way impair the safe movement of traffic on any street or highway. C. Screening shall be erected to prevent headlight glare from commercial or industrial land uses from shining onto adjacent

residential property. No screening shall in any way impair safe vertical or horizontal sight distance for any moving vehicles, or be closer than thirty (30) feet to any street right of way line.

D. In addition to 24.04(A) and (B) above, outdoor lighting or lighting designed to be seen from the exterior shall comply with the following standards except as provided for in Section 24.04(E) below: 1. Lighting shall be designed and constructed to insure that direct and reflected light, unless part of a street lighting or

access road lighting program, is confined to the lot or parcel upon which the light source is located. 2. Lighting shall be so installed that the surface of the source of light shall be hooded or louvered so that the light source

shall not be visible and shall be so arranged as far as practical to reflect light away from any residential use, and in no case shall more than one foot candle power of light cross a lot line five (5) feet above the ground in a residential district.

3. Lighting fixtures shall have a one hundred (100) percent cut off angle above the horizontal plane at the lowest part of the light source so that light rays shall not be emitted by the fixture at any angle above this horizontal plane, as may be certified by photometric tests. The intensity of light at any angle above a cut off angle of seventy-five (75) degrees shall be less than ten (10) percent of the peak candle power for the light fixture.

4. No light source shall exceed the height of the tallest structure on the lot or parcel, and in no case shall a light source exceed a height of twenty-five (25) feet, measured from the ground or pavement closest to the light source.

5. All illuminated signage or any lighting associated with a sign shall be turned off between the hours of 10 p.m. and 5 a.m. If a non-residential use is open to patrons or members any time between the hours of 10 p.m. and 5 a.m., illuminated signage or any lighting associated with a sign may be kept on so long as such illumination meets the standards of the Township Ordinances and so long as such illumination is turned off during the hours the use is closed to patrons and members.

E. Outdoor lighting which need not comply with the standards of Section 24.04(D) above shall be limited to: 1. Residential lawn, dock, and decorative lighting provided the light source is less than six (6) feet in height from the

closest ground or pavement. 2. Seasonal lighting associated with holidays, such as Christmas and Halloween. 3. Outdoor recreation and amusement areas, provided the light sources are mounted at a sufficient height, designed with

baffling and glare guards to assure that no more than one foot candle power of light shall cross a lot line five (5) feet above the ground in a residential district, and turned off during hours the facility is closed to the public.

4. Neon lighting for non-residential uses, provided it is turned off between the hours of 10 p.m. and 5 a.m. If a non-residential use is open to patrons or members any time between the hours of 10 p.m. and 5 a.m., neon lighting may be kept on so long as such illumination meets the standards of the Township Ordinances and so long as such illumination is turned off during the hours the use is closed to patrons and members.

Section 24.05: COMMERCIAL and INDUSTRIAL USES All land uses and structures within commercial or industrial zoning districts shall conform to the following standards: A. No major repairs or refinishing shall be done outside of the principal structure. B. The intensity level of sounds shall not exceed the following decibel levels when adjacent to the following types of uses:

Decibels (dba) Adjacent Use Where Measured 55 Residential Dwellings Common Lot Line 65 Commercial Common Lot Line 70 Industrial and Other Common Lot Line

Objectionable noises due to intermittence, beat frequency, or shrillness, shall be muffled so as not to become a nuisance to adjacent uses.

Dexter Township Zoning Ordinance Article 24: Environmental Standards

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C. All machinery shall be so mounted and operated as to prevent transmission of ground vibration exceeding a displacement of .003 of one inch measured by any lot line of its source.

D. Any operation producing intense glare or heat shall be performed within an enclosure so as to completely obscure and shield such operation from direct view from any point along the lot line except during the period of construction of the facilities to be used and occupied.

Section 24.06: STORM WATER MANAGEMENT A. On-Site Detention: All lots shall retain storm water runoff on-site, or detain it so as to allow discharge without any impact on

adjacent lands or surface water bodies. No land uses shall be permitted which will increase the rate of runoff discharge from a lot or parcel or otherwise cause erosion or direct sedimentation upon abutting properties including an abutting street or surface water body. No land uses shall be permitted which will reduce the level of service currently being provided by existing storm water management infrastructure or existing drainage patterns. Direct discharging of untreated storm water to a water body is prohibited.

B. Storm Water Standards for Plot Plans: A storm water management plan shall be required for all plot plans that either do not comply with Section 24.06(A) or have impervious surface areas that exceed twenty percent (20%) of the lot. 1. Capacity: All required storm water management systems shall be designed, installed, and maintained to capture and

treat the first one (1) inch of storm water runoff from all existing and proposed impervious surfaces. For example purposes only, if a subject parcel has a lot coverage of 1,000 square feet and an impervious patio of 200 square feet, the site must have a storm water management system that can retain on-site or detain at least 100 cubic feet of storm water and allow the storm water to naturally permeate into the soil. The approving authority may require a more voluminous storm water management system if the proposed land use, slope, or underlying soil types are expected to increase the rate of runoff discharge from the parcel.

2. Storm Water Management Plan: In addition to the data required for Plot Plans in Section 6.03(A), all required storm water management plans shall include the following data on the Plot Plan: a) Current and proposed impervious surface area calculations. b) Current and proposed storm water calculations. The amount of storm water created during a one (1) inch rain

event shall be calculated. This volume is calculated by dividing impervious surface area by twelve (12). c) Current and proposed locations of gutters, downspouts, and points of discharge. d) Current storm water runoff patterns and flows, and any existing storm water management system(s) on the site. If

the Township Engineer deems the existing storm water management system to be functional, the owner may deduct the amount of storm water that the existing system captures and treats in a one-inch rain event from the total required capacity.

e) Storm water volume calculations pursuant to Section 24.06(B)(1). The volume calculations shall use proposed void ratios of selected backfill material, if applicable.

f) Design, installation, and maintenance guidelines of proposed storm water management system. This system shall include one (1) or more of the Best Management Practices (BMPs) described in the “Low Impact Development Manual for Michigan: A Design Guide for Implementers and Reviewers,” published by the Southeast Michigan Council of Governments (http://www.semcog.org), or similar publication.

g) A maintenance schedule. 3. Performance Guarantee: Prior to Dexter Township’s review of the storm water management plan, the applicant shall

submit a performance guarantee (cash, certified check, irrevocable bank letter of credit, surety bond, or similar instrument acceptable to the Township Clerk) to Dexter Township per Section 3.05 of this ordinance. The amount of this performance guarantee shall be established by the Township Board of Trustees and shall be sufficient for Dexter Township to cover the plan review fees and subsequent field inspection fees of the Township Engineer in the event that the applicant fails to reimburse Dexter Township for them.

4. Review: The storm water management plan shall be reviewed for compliance by the Zoning Administrator and the Township Engineer prior to issuance of a Zoning Permit. The property owner shall reimburse Dexter Township for the cost of the Township Engineer’s review(s).

5. Construction and Inspection: All required storm water management systems shall be constructed in accordance with the approved plans. After all work has been completed, the storm water management system shall be inspected for compliance by the Zoning Administrator and the Township Engineer prior to final approval of the Zoning Permit. The property owner shall reimburse Dexter Township for the cost of the Township Engineer’s inspection(s).

6. Maintenance: All storm water management systems required under this section shall be properly maintained so as to comply with the requirements herein. Prior to final approval of the Zoning Permit, the property owner shall sign and record with the Washtenaw County Register of Deeds a Storm Water Management Practices Maintenance Agreement on a form provided by Dexter Township. This Agreement shall also be binding on future property owners. Any proposed changes by the property owner to the storm water management system or the Agreement shall be reviewed and decided by Dexter Township in the same manner as a new application under the storm water management standards at the time the change is proposed.

Dexter Township Zoning Ordinance Article 24: Environmental Standards

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End of Article 24

Environmental Article 17

Dexter Township Zoning Ordinance Ordinance Number (08.07.2017 ΔΔΔK) Page 17-7

§17.40 - WATER QUALITY & QUANTITY

The following standards are intended to protect existing waterbodies and wetlands from negative impacts of polluted or excessive stormwater.

(A) Existing Features: Existing waterbodies and wetlands shall be protected from damaging modifications and adverse changes in stormwater runoff quality and quantity associated with development or improvements.

(B) Special Significance: Waterbodies and wetlands of special significance, including, but not limited to, forested wetlands, fens, wetlands associated with watercourses, and watercourses with intact native plant ecosystems shall be protected from development and the effects of development.

(C) Stormwater: Stormwater discharge into existing waterbodies and wetlands shall not modify the existing water levels or flow rate.

(D) Direct Discharge: Direct discharge of untreated stormwater into a waterbody or wetland shall be prohibited. Stormwater may only be discharged into a waterbody or wetland if it has been designed for that and will be pretreated by a sedimentation trap, sump, or basin to remove sediments and other pollutants. The sediment trap shall be constructed and stabilized before other site grading may take place.

(E) Construction: Stormwater treatment facilities shall be installed as soon as possible during construction.

(F) Impacts: Any proposed impacts to waterbodies and wetlands shall be permitted by and adhere to applicable regulations of the Department of Environmental Quality or Water Resources Commissioner.

§17.45 - STORMWATER MANAGEMENT

The following standards apply whenever there is an increase in impervious coverage on a property in order to protect the quality of waterbodies and wetlands and the general environment in the Township.

(A) General Provisions: All properties shall comply with the following standards for stormwater.

(1) Pretreatment: Stormwater shall not be discharged directly into a waterbody or wetland without some form of pretreatment to remove sediments and other pollutants, as outlined in §17.40(D): Direct Discharge.

(2) On-site Detention: All sites shall retain stormwater onsite or shall detain it to allow discharge without a negative impact on adjacent properties, streets, waterbodies, or wetlands.

(3) Natural Drainage Patterns: Alterations to natural drainage patterns shall not increase runoff, create flooding, or contribute water pollution to adjacent or downstream lands.

(4) Adverse Impacts: Stormwater shall be managed in a manner to prevent flood hazards and water pollution related to runoff, soil erosion, and channel erosion.

(5) Level of Service: Land shall not be altered in a manner that will reduce the level of service currently being provided by an existing storm water system or the natural drainage patterns.