STORMWATER
MANAGEMENT PLAN
TOWN OF WILLISTON, VERMONT
I.
INTRODUCTION:
The Clean Water Act of 1972, as amended in 1987, sets forth requirements for meeting the clean water standards of the Act. The Phase I requirements addressed large contributors to water pollution while phase II was designed to address smaller contributors. Of special interest to Williston are the requirements spelled out for operators of small Municipal Separate Storm Sewer Systems (MS4s), particularly those that discharge into rivers or streams identified as impaired. Williston operates an MS4, and is part of two watersheds classified as impaired waters (Allen Brook and Muddy Brook). Williston is therefore subject to the Phase II requirements.
Water quality is impaired by a variety of contaminants that can be roughly grouped into four basic categories: toxins, pathogens, nutrients, and sediments. Toxins are chemical materials that tend to harm living organisms. Pathogens are living organisms (bacteria) that cause disease in animals (including humans). Nutrients are chemical compounds that stimulate growth of living things, primarily microscopic organism and plant life. Sediments are small particles of soil or mineral compounds that are temporarily suspended in the water and that may be deposited at other, downstream locations. Research has determined that, while toxins and pathogens may occasionally be present in the waterways draining Williston, the most troublesome contaminants are nutrients and sediments. Indeed, research has also determined that the most common nutrient, phosphorous, tends to bind with sediments, thus compounding the problem.
According to the Williston Water Quality Report prepared by the Vermont Department of Environmental Conservation in January, 2003, sampling data from the Allen Brook showed improving scores of “Good” and “Excellent” and passing grades regarding both the insect and fish communities[1]. The Williston Water Quality Report also indicated that the Muddy Brook had deteriorated over recent years, with a score of “P” (Poor) for clean water species, and a failing grade for the insect community. An important tributary of the Muddy Brook received scores of “P” (Poor) for nutrient index and clean water species, and a failing grade for insect community. The report concluded by noting that improvements could be obtained by reducing or attenuating stormwater runoff and stormwater erosion. The Town is awaiting issuance, by the Department of Environmental Conservation, of Watershed Improvement Plans (WIPs) for the Allen and Muddy Brooks.
Stormwater contributes to surface water quality in a number of ways, the most obvious being the ability to wash contaminants off the landscape and into the streams and ponds, and the ability to carry eroded sediments into streams and ponds. In a more natural state where much of the land area is covered with vegetation, stormwater is allowed to penetrate into the ground where sediments are filtered out, pathogens are diluted or allowed to expire, and nutrients are utilized by nearby vegetation. In more developed areas more of the land surface is covered with impervious surface (roofs, roads, sidewalks, parking lots, etc.). Stormwater has less opportunity to penetrate the earth, and is often channeled, collected, and diverted rapidly away from developed sites, often being discharged directly into streams or other waterbodies. The natural treatment capabilities of the soil and vegetation are bypassed.
Traditionally, stormwater management has concentrated on collecting stormwater and quickly removing it from developed areas in order to prevent local flooding and property damage. In the past decade or so, it has been recognized that this practice can increase flooding and other problems in the receiving waterbodies, and does very little to treat for stormwater contaminants. This has led to attempts to detain stormwater and release it at a controlled rate over an extended period of time. Even with detention, the amount of stormwater that is allowed to enter the soil and be naturally cleansed diminishes as the amount of impervious ground cover increases. This problem is exacerbated as we attempt to create more compact settlements separated by open space.
In Vermont, the primary regulation of stormwater has been through the Stormwater Discharge Permit process administered by the Agency of Natural Resources (ANR). This was targeted at developments where five acres of land or more were to be disturbed. Smaller projects have only recently become subject to such scrutiny. In Williston, approximately 100 Discharge Permits have been issued by the ANR. Many of these have expired, and there has been little effort to ensure that the approved stormwater facilities have been properly installed or maintained. Recent decisions by the Vermont Water Resources Board have resulted in increasing pressure on the State to fulfill its obligation to enforce the conditions of these existing discharge permits.
Under Phase I of the Clean Water Act, the State's responsibility for permitting applied to developments containing five or more acres of disturbed land. Under Phase II, that jurisdiction has been expanded to include development with one or more acres of disturbed land. In 2002, the State of Vermont adopted stormwater rules and requirements that apply to developments which result in one acre or more of impervious surface.
At the local level, Williston has generally relied on the State review and Discharge Permit process. Developers were asked to provide copies of their Discharge Permits, but the Town made no attempt to review stormwater management designs. For smaller projects not subject to Discharge Permits, the Town only recently has been requiring developers to submit calculations demonstrating that the post development rate of discharge from the site would not exceed the predevelopment rate of discharge.
Stormwater management is not a problem that must be addressed only by private development. Publicly owned properties and, most importantly, publicly owned roads are important elements in the overall stormwater system. In many cases, storm water collected from Town owned roads is discharged into private swales and detention ponds. On older roads water may be collected by roadside ditches and discharged into nearby swales, wetlands, or streams.
As a result of many decisions made over past decades, the stormwater management system in Williston (as in most other Vermont Towns) is a hodgepodge of public and private elements, sometimes independent, sometimes related, sometimes permitted, sometimes not. Under the Phase II requirements, it will be necessary to sort all of this out, determine just what the over-all system is, and to then take steps to ensure that stormwater does not contribute to additional impairment of our streams and ponds.
II. THE PHASE II PLAN REQUIREMENTS:
As noted above, Phase I requirements of the 1972 Clean Water Act focused on large dischargers while Phase II focused on small dischargers, including small MS4s. Since permits under Phase I were issued by the State, it is the State's responsibility to monitor and enforce the conditions of Phase I discharge permits.
Phase II requirements become applicable in 2003, and apply to small MS4s, of which Williston is one.
· Each small MS4 must develop, implement, and enforce a Stormwater Management Plan designed to reduce the discharge of pollutants to the Maximum Extent Practicable (MEP), to protect water quality, and to satisfy the appropriate water quality requirements of the 1972 Clean Water Act.
· The Small MS4's Stormwater Management Plan must include the following six Minimum Control Measures:
· Public Education and Outreach;
· Public Participation;
· Illicit Discharge Detection and Elimination;
· Construction Site Runoff Control;
· Post Construction Runoff Control; and
· Pollution Prevention/Good Housekeeping.
There appear to be three options available to small MS4s for meeting the Phase II requirements:
· A small MS4 may obtain coverage under a General Permit issued by the Agency of natural Resources;
· A small MS4 may participate in the implementation of a Stormwater Management Plan developed by an existing Phase I (large) MS4 or a neighboring small MS4 as a co-permittee; or
· A small MS4 may obtain an individual permit.
In Chittenden County, the preferred approach is the first of the above, and the Vermont Agency of Natural Resources plans to issue General Permit 3-9014 for small MS4. This Stormwater Management Plan is attached to Williston’s Notice Of Intent (NOI) to apply for permit coverage under the General Permit conditions. As a part of the NOI, the MS4 must include a description of its Stormwater Management Program, including Best Management Practices (BMPs) and Measurable Goals for each of the six required Minimum Control Measures.
It must also be noted that the Agency of Natural Resources plans to issue Watershed Improvement Plans (WIPs) for the watersheds of most streams listed as being impaired. Since Williston includes at least some of the area in two such watersheds, Williston's Stormwater Management Plan will need to respond to the WIPs for the Allen and Muddy Brooks.
III.
WILLISTON'S STORMWATER
MANAGEMENT PLAN
Under the provisions of Phase II, a small MS4 is required to design and implement a comprehensive Stormwater Management Plan (based on the six minimal control measures) to reduce pollutants to the Maximum Extent Practicable (MEP). The Stormwater Management Plan must spell out not only the Best Management Practices (BMPs) to be used to achieve each of the six minimal control measures, but must also set forth a set of Measurable Goals (time lines, implementation objectives) to be used to track implementation and effectiveness of the BMPs. The Environmental Protection Agency recommends that the Measurable Goals for each Minimal Control Measure include, where appropriate, the following: 1) The activity or BMP to be implemented; 2) A schedule of dates of completion; and 3) a quantifiable target for measuring progress towards achieving the BMP.
The EPA also recommends that MS4s tailor their Stormwater Management Plans to reflect local water quality needs, local priorities, and other local factors. What follows is a Stormwater Management Plan developed for the Town of Williston, but which recognizes that some BMPs, particularly those relating to the first Minimum Control Measure, are best developed and implemented cooperatively on a multi-jurisdictional basis.
The Six Minimal
Control Measures and How They will be Addressed.
Minimum
Control Measure 1 - Public Education and Outreach:
Public education and outreach are important for three reasons:
Williston has, and will continue to initiate public education efforts related to stormwater and water quality issues. Over the past two years the Town has participated in two significant watershed studies, both of which have involved public education activities.
· The Allen Brook Study is a prototype TMDL study sponsored by the Department of Environmental Conservation. It was initiated in response to the Phase II water quality requirements under the Federal Clean Water Act. As of October of 2001 (when the interim report was produced) this study has;
- Produced a large poster describing the project for display at the local library;
- Produced and distributed a survey designed to both raise awareness of the Allen Brook and its problems and to solicit input on remediation efforts;
- Produced two articles for publication in the Williston Whistle;
- Conducted a meeting with Williston residents and officials;
- Made a presentation to the Selectboard;
- Organized two "river walks" (advertisements included posters, local newspaper notices, and phone invitations);
- Held four "kitchen meetings" with landowners;
- Created a database of 78 interested residents and brook abutters who will receive future notices;
- Met with representatives of the development community;
- Met with the Town Conservation Commission.
Since that time the consultants have met with a steering committee of business interests and presented preliminary recommendations to the Town Planning Commission.
· The Sucker Brook Stabilization Study was intended to develop specific plans for the stabilization of a portion of the Sucker Brook (a tributary of Muddy Brook) which had experienced a major washout that imposed a huge sediment load on the Sucker Brook and thence into the Muddy Brook. Most public outreach efforts of this study have involved notification and communication with abutting property owners. There have also been several site walks with consultants and property owners, and a major effort to remove junk cars and other debris from the stream. Finally, there was a formal public meeting to present results and recommendations of the study. There will certainly be several follow up meetings as the work is implemented.
· For several years the Town of Williston has maintained a web page (http://town.williston.vt.us) which contains a variety of information about the Town and Town activities and events. The Town is currently developing an environmental education page for its web site, which will include items on various environmental issues. Prominent among them will be water quality, stormwater management and erosion control. The Town anticipates continuing and improving this site for the foreseeable future.
· Best Management Practices: The General Permit for MS4s issued by the Vermont DEC (Permit 3-9104) spells out three distinct approaches that MS4s may follow to satisfy the requirements of this Minimum Control Measure:
1. The MS4 may participate in a regional stormwater education and outreach strategy described in a Memorandum of Understanding (MOU) between a number of MS4s and the Chittenden County Regional Planning Commission, and endorsed by the Vermont DEC (Attachment A), and maintain a web site featuring relevant water quality and stormwater management items,
2. The MS4 may submit for approval a plan based on specified EPA guidelines; or
3. The MS4 must undertake all of a set of specific activities listed in the General Permit.
Williston has elected the first of these options and has signed the MOU. The program defined in the MOU, at a minimum, focuses on the development and airing of public service announcements on television, radio and in print media. The Chittenden County Regional Planning Commission will serve as lead agency for the regional approach, under the overall guidance of a steering committee made up of representatives of all participating MS4s.
In addition, Williston will continue to develop and maintain the environmental education page on its web site, seeking to provide a variety of items addressing water quality, stormwater management and erosion control issues. The Town will establish, on its web site, direct links to other sources of relevant information.
1. In the first year of the planning period the regional group will focus on program organization and on the production of one Public Service Announcement (PSA) spot for play on radio, television and in the print media.
2. In each of years 2 through 5, a minimum of one PSA per year will be developed for radio, television and print media.
3. In each of years 2 through 5, media time will be purchased to air the PSAs developed in the previous years.
4. In each of years 2 through 5, other products meeting EPA and Vermont DEC requirements, within the limitations of the regional approach's budget, will be pursued.
5. In the first year of the planning period the Town will bring the environmental education page of its web site on line and populate it with a minimum of four relevant items.
6. In each of years 2 through 5, the Town will add items to its environmental education page as they become available.
Minimum
Control Measure 2 - Public Participation:
·
General Discussion: After going to considerable effort to
educate the public about stormwater issues and stormwater management practices,
it is appropriate to provide an effective means for the educated public to
participate in the overall stormwater management program. Such participation is valuable for several
reasons:
- Members of the public can bring a wide range of knowledge and expertise to the discussions, thus facilitating better decisions.
- Participation will engender broader awareness of and support for the resulting public stormwater management program.
- Broader support can reduce obstacles and challenges, and thus speed up implementation of the program.
There are two aspects of participation. One is to provide a vehicle for participation in public discussions and decisions on stormwater management. The other is to provide specific hands-on actions that Town residents and business owners can take to reduce stormwater problems.
The General Permit for MS4s (3-9014) requires that each MS4 undertake at least three from a list of eight specific public participation activities. Williston has chosen to undertake the following: 1) An on-going series of public forums/discussions about stormwater management; 2) A continuing storm drain stenciling project; and 3) An "adopt-a stream" program. These efforts will be described in more detail below.
1. An on-going series of public forums/discussions about stormwater management: Participation needs to be tied directly to implementation actions, and for this reason the Town has tailored this public participation effort to link directly with activities under other Minimal Control Measures. The Town envisions that much if its implementation efforts regarding construction and post-construction runoff control (Minimum Control Measures #4 and 5) will be done via the development and adoption of amendments to its Zoning Ordinance, Subdivision Regulations, or Public Works Standards. In at least the first two cases, it is anticipated that the Planning Commission will hold at least one publicized public forum/work session to discuss stormwater management problems and explore ways of addressing those problems. Due to the nature of the problems, it is anticipated that experts from the Department of Environmental Conservation, the University of Vermont, and elsewhere will be invited to provide technical assistance to the forums/workshops.
With this input, the Planning Commission and staff (and consultants retained specifically for this purpose) will begin to prepare language for the proposed amendments.
The Planning Commission will have several public work sessions and at least one formal public hearing to consider the draft language before voting to approve it for transmission to the Town Selectboard. The Selectboard, in turn, will hold a first reading of the proposed amendments at a public meeting and will hold at least one formal public hearing before adopting the proposed amendments. Taken as a whole, this process provides a variety of public participation venues ranging from exploratory workshops to formal public hearings. After the ordinances have been adopted an in place for a substantial time period, a final workshop will be convened to assess performance
2. An on-going "storm drain stencilling" program: This is an important opportunity to provide actual hands-on participation in stormwater management activities. The Town will initiate a program in which volunteers apply stencilled messages to storm drains advising people not to dump substances other than rainwater because the basins drain directly into water courses. Such a program has a double benefit. First it provides a valuable message at the place and time where people might be considering disposal of a polluting substance. Second, by having townspeople actually do the stenciling, it provides hands-on involvement in water quality protection. The Town will initiate a program similar to those used by South Burlington and other towns. The Town will work to involve community groups such as service clubs, school groups and extracurricular clubs, boy/girl scouts, and others. The program will begin in the first year of the planning period and extend over five years until all catch basins are stenciled. The Town will continue to search for a longer lasting, less maintenance intensive method for conveying the stencilled message.
3. An "Adopt-a stream" program: Finally, the Town will attempt to establish a volunteer "adopt-a-stream" program. This will be a follow up to the current Sucker Brook Stabilization program. The effort will involve the Town Conservation Commission, Town staff, schools or community groups, and interested individuals. Individual stretches of streams will be identified for "stream walks". Debris swill be removed as necessary and maintenance needs will be identified. This will be an on-going effort aimed at identifying and stabilizing small problem sites when they are identified and spotting potential larger problems in time to take preventative action.
·
Best management Practices:
1. No later than the beginning of year 2, prior to development of amendments to the Town's Zoning Ordinance, Subdivision Regulations, and Public Works Standards to address Construction site runoff control and Post Construction Runoff control, the Planning Commission will conduct at least one public forum/workshop. At this session, experts will discuss the problems and the public will explore approaches to effective runoff management.
2. In year 2 the Planning Commission will hold several public work sessions to consider and refine proposed language for construction site runoff control requirements in the Zoning Ordinance, Subdivision Regulations, and Public Works Standards.
3. In year 2 the Planning Commission and the Selectboard will hold public hearings to consider proposed amendments to the Zoning Ordinance, Subdivision Regulations, and Public Works Standards related to construction site runoff control and post construction runoff control.
4. In the first year of the planning program the Town will initiate an on-going program of catch basin stencilling, with the objective of stencilling 200 to 250 basins per year until all basins in Town have been stencilled.
5. In the third year of the planning program the Town will initiate a stencil maintenance program where Town staff is instructed to inspect catch basin stenciling and re-do the stencilling if needed, every time they clean a basin that is already stencilled.
6. Beginning in year 3 the Town will attempt to institute a voluntary "adopt-a stream" program in which citizens, in conjunction with the Town Conservation Commission, Town staff, the schools, and other groups periodically to undertake minor maintenance and monitoring.
·
Measurable Goals: The following measurable goals will serve as benchmarks for
the effective implementation of the above Best Management Practices.
1. By early in year 2 the Planning Commission will have held at least one public forum/workshop to for public input regarding ordinances directed at control of construction site runoff and post construction runoff.
2. By the end of year 2, the Planning Commission will have held a series of public work sessions and formal public hearings on proposed amendments to the Zoning Ordinance, Subdivision Regulations, and Public Works Standards pertaining to control of construction site runoff and post construction runoff.
3. By the end of year 2 the Selectboard will have held a discussion of the proposed amendments at a public meeting and at least one public hearing on the proposed amendments.
4. In Year 1 the Town will institute a voluntary, on-going catch basin stencilling program with the target of stencilling between 200 and 250 basins each year.
5. In year 3 the Town will institute the stencilling maintenance program in conjunction with routine catch basin cleaning. This will become an on-going operation.
6. Beginning in year 3 the Town will initiate an on-going, voluntary, "adopt-a stream" program. One or more "stream walks" will be conducted on identified stretches of streams each year. Needed maintenance will be scheduled as soon as practicable.
Minimum
Control Measure 3 - Illicit Discharge Detection and Prevention:
·
General Discussion: For purposes of stormwater management, an
illicit discharge is defined by Federal Regulations as "any discharge to
an MS4 that is not composed entirely of stormwater....", with exceptions
for certain NPDES-permitted industrial sources and discharges from fire
fighting activities. Since MS4s are not
designed to treat non-stormwater wastes, these illicit discharges result in
untreated wastes being discharged directly to the receiving waters.
Non-stormwater wastes can enter a stormwater system in a variety of ways, including accidental spills, surface disposal of wastes, dumping of wastes into stormwater catch basins, or conscious (but illegal) connection of waste lines to the stormwater system. With the exception of accidental spills, these are all conscious decisions which can be addressed (at least in part) by effective educational programs.
The final Phase II Stormwater Management Rules require small MS4s to develop, implement and enforce an illicit discharge detection and elimination program which must include at least the following elements:
1. A Geographic Information System (GIS) based map of the stormwater systems showing all outfalls and the names of all receiving waters, and which may include all separate private stormwater systems within the MS4 boundaries;
2. A prohibition (via ordinance or other regulatory mechanism) on non-stormwater discharges into the MS4, along with appropriate enforcement mechanisms;
3. A plan for detecting and eliminating non-stormwater discharges, including illegal dumping, into the MS4;
4. An educational program specifically addressing illegal discharges; and
5. By January 1, 2008, provide the Secretary of the Agency of natural Resources with a summary report of monitoring activities and corrective actions taken (if any).
Note that Section 4.2.3.1.6 of the General Permit for MS4s requires that the Town's efforts under this minimal control measure address a number of specifically identified discharges or flows only if they have been identified as significant contributors of pollutants to the Town's MS4. To date, none of those specifically identified flows or discharges have been identified as significant polluters in Williston.
· The Williston Context: Williston, Vermont, is a small town in Chittenden County on the outskirts of the urbanizing area surrounding the City of Burlington. Thirty years ago Williston was a small rural, agricultural community with very little non-residential/non-agricultural development. In the past two decades the Town's population has more than doubled to just over 8,000 persons, and the Town has become one of the largest retail centers in the State.
The implications of this are several. First, since most development in the Town occurred within the past twenty years, it was subject to intense scrutiny at both the local and regional/state level. Local Subdivision and Zoning regulations addressed sanitary waste and stormwater control, as did Act 250 review at the regional/state level. Large projects required Stormwater Discharge Permits from the Vermont Agency of Natural Resources (approximately 100 such permits were issued to developments in Williston). Virtually all development in Williston was subject to some level of formal review that addressed sanitary and storm sewer needs.
Second, the Town's sanitary sewer system is very new. It was constructed to contemporary standards and should not contain significant failures or leaks. Similarly, the newness and the review procedures make it very unlikely that non-stormwater waste lines have been connected to the storm water system. Most illicit discharges of which the Town is aware have resulted from accidents or occasional dumping rather than from improper connections. It should also be noted that the Williston Fire Department is one of only a few certified hazardous materials response squads in Chittenden County, and is trained to control toxic spills and prevent them from entering the storm sewer system and/or water bodies.
Like most Vermont communities, Williston did not set about to consciously create a definable stormwater system. Historically, stormwater from public roads was collected in open ditches and conveyed to available swales or streams. More recently, new Town roads may have catch basins and underground piping systems that convey the water either to available swales or to detention ponds which, in turn, discharge into available swales, streams, etc. In many cases the detention ponds are actually private. Stormwater on individual development sites may be conveyed by sheet flow or pipes to detention ponds before being discharged off-site. As a result, Williston's Municipal Separate Storm Sewer System is somewhat difficult to define. It is not continuous. It has many separate outfall or discharge points, and some of the outfall points may be private. The Town is currently working with the Chittenden County Regional Planning Commission to create a GIS based map of its Municipal Storm Sewer System.
For almost two decades the Town has had its own Health Regulations which include provisions for on-site septic systems. The Town's Health Officer, in conjunction with the Zoning Administrator, is responsible for identifying failed systems and seeing that they are repaired or replaced. This is an ongoing process and will be continued.
·
Best Management Practices: The following have been identified as Best Management
Practices for detecting and eliminating discharges of non-stormwater waste into
Williston's municipal storm sewer system:
1. Map of Municipal Storm Sewer System: Williston first prepared a map of its stormwater systems several years ago and is currently working with the Chittenden County Regional Planing Commission to update that map and convert it to a GIS format. This will be completed to meet EPA requirements and will show all outfall points and identify all receiving waters. This should be completed by the end of the summer in 2003. This map will be based on existing Town maps, Town approved plans, Town provided as-built plans, State approved Discharge Permits, and digital plans provided by developers.
2. Map Updating: The Town will update this map annually on the basis of local permits and State issued Stormwater Discharge Permits. Developers will be asked to provide plans in digital (CAD) format which can be readily integrated into the Town's GIS based Stormwater System Map.
3. Discharge Ordinance: The Town, working with counsel, will develop and adopt an ordinance making it illegal to discharge non-storm waste into any storm sewer system in the Town, including the municipal storm sewer system. The ordinance will include enforcement and fines as provided under State law.
4. Monitor System Outfalls: While the Town is not aware of any inappropriate connections to its municipal storm sewer system, the Town proposes to systematically monitor the outfall or discharge points. Monitoring will concentrate on the industrial and commercial areas of the Town, as that is where the greatest potential for illicit discharges seems to be. Monitoring will include dry weather examination to identify non-storm based flows, as well as quality checks during normal operation of the system. Approximately 25 percent of the discharge points will be monitored each year. The dates and results of monitoring will be incorporated as attributes to outfalls on the GIS based Stormwater System Map and data base.
5. Elimination of Illicit Discharges: If monitoring or other information identifies an illicit discharge, the Town will take appropriate steps to locate the source and terminate the discharge. It is anticipated that most of these events will be sporadic individual dumps or accidental spills. Fines and clean-up charges will be assessed against those responsible for the illicit discharges in accordance with the discharge ordinance described above, or state law.
6. Detection of Failed Septic Systems: Detection and remediation of failed septic systems. This process, described above, is an on-going process administered by the Town Health Officer.
7. Educational Outreach: In general, the educational outreach efforts described under previous minimal control measures will be helpful in detecting and eliminating illicit discharges. The more people are aware of stormwater issues, the more likely they are to avoid accidental or thoughtless discharges, and to report such discharges when they are found. The Town's on-going public education and outreach efforts will certainly mention the problem of illicit discharges. In addition, the Town will provide training for public employees on the identification and elimination of illicit discharges from municipal operation. Reminder flyers will be distributed with pay slips once each year thereafter.
8. Catch Basin Stenciling: As described under minimum control Measure 2, Williston plans to initiate a catch basin stencilling program that discourages dumping of pollutants into stormwater catch basins. This will be a voluntary program involving various community groups. The intent is to stencil some 200 to 250 catch basins per year.
9. Household Hazardous Wastes: Recycling provisions for household hazardous wastes. This is already in place through the Chittenden Solid Waste District.
10. Report to the Secretary of ANR: No later than January 1, 2008, a report will be submitted to the Secretary of ANR describing the Town’s monitoring efforts, the results of such efforts, corrective actions taken, and the disposition of any illicit discharges identified.
·
Measurable Goals: The following measurable goals will serve as benchmarks for
the effective implementation of the above Best Management Practices.
1. Complete Map of Storm Sewer System: A complete GIS based map of Williston's storm sewer system will be completed by the end of summer in 2003 (during year 1 of the Permit period).
2. Annual Map Update: The Town will update the stormwater system map annually on the basis of local permits and state issued stormwater permits.
3. Outfall Monitoring: Beginning in year 2 of the permit period, at least 25 percent of the outfalls of Williston's storm sewer system will be monitored each year, beginning with those in the industrial and commercial districts. At a minimum, monitoring will include visual and olfactory factors. In addition, citizens will be encouraged to report unusual discharges whenever they are sighted.
4. Failed Septic Systems: The Town will continue its current process of detecting and remediating failed septic systems throughout the five year permit period.
5. Adoption of no-discharge ordinance: By the end of year 2 of the permit period the Town will have adopted an ordinance prohibiting the discharge of non-storm water waste into the any storm sewer system, along with appropriate enforcement mechanisms.
6. Public Education and Outreach: See measurable goals under Minimum Control Measure number one.
7. Education Program for Public Employees: In year 2 of the permit period the Town will present an education program to all public employees focussed on the prevention of illicit discharges into the storm sewer system. Reminder flyers will be distributed with pay slips once each year thereafter.
8. Catch Basin Stencilling: As described in Minimum Control Measure 2, the Town of Williston will initiate the catch basin stencilling effort in year 2 of the permit period. It is expected that 200 to 250 catch basins will be stenciled each year for four years. Local groups and service clubs will be encouraged to take over the program and ensure that the stenciling is updated as needed. Stencilling will also be checked and updated as part of ongoing catch basin cleaning efforts.
9. Household Hazardous Wastes: The Town will continue its ongoing arrangement with the Chittenden Solid Waste District for recycling household hazardous wastes throughout the five year permit period.
10. Report to the Secretary of ANR: No later than January 1, 2008, the Town will submit the report described above to the Secreatary of ANR.
Minimum
Control Measure 4 - Construction Site Runoff Control:
·
General
Discussion: There is no question
that construction sites are potentially major sources of suspended solids in
stormwater runoff. Construction
generally requires that the protective vegetative cover be removed and the
underlying soil exposed to wind, rain and other forms of erosion. It has been estimated that sediment runoff
rates from construction sites are typically 10 to 20 times greater than those
of agricultural lands, and 1,000 to 2,000 times greater than those of forest
lands[2]. These sediment loads can overwhelm the
receiving streams and cause physical, chemical and biological harm to the
State's waters.
The General Permit for MS4s issued by the Secretary of the Agency for Natural Resources (ANR) requires that all small MS4s to develop and implement an effective construction site runoff control program. Such a program must include the following elements:
1. Establishment of a procedure for identifying construction activities meeting the one acre and five acre thresholds, and for reporting such activities to the Secretary of ANR.
2. Establishing procedures to assist the Secretary of ANR in inspecting permitted construction sites by reporting signs of non-compliance such as eroding soil and turbid waters.
3. Establishment of procedures to ensure that construction activities undertaken by the Town are properly permitted and implemented in accordance with the terms of the General Permit for MS4s.
4. Review of the Town's existing policies and ordinances (Planning, Zoning, Subdivision, Public Works Standards) regarding their effectiveness in managing construction related erosion and sediment and controlling waste, and with the requirements of the General Permits for large and small construction sites.
5. Adoption of an erosion control ordinance, planning, zoning or subdivision regulation, or other regulatory mechanism for development activities not subject to state or federal controls.
·
The Williston Context: Williston has attempted to control
stormwater runoff from all sites through three formal mechanisms.
1. Section 1080 of the Town's Subdivision Regulations specifically addresses storm drainage, although it tends to focus on removal of stormwater rather than on sediment control and treatment. Subdivision Regulations apply when land is divided into smaller lots and to certain large developments such as Planned Residential or Planned Unit Developments.
2. All development except of one and two family dwellings is reviewed under Site Plan Approval (Section 4.1 of the Town's Zoning Ordinance). With the exception of construction of roads and associated work on water, sewer and drainage, Town construction projects are also subject to Site Plan Approval. The Town's Final Site Plan Checklist calls for information of storm drainage facilities, and this is supported by Sub-Paragraph 4.1.1-A-2-vi of the Zoning Ordinance. While historically the emphasis has been on removal of storm water, more recent reviews have included sedimentation/detention basins to control both quality and quantity of runoff leaving the site.
3. Construction of any facilities that are intended to be (or may be) conveyed to the Town must meet the Town's Public Works Standards. These specifications address such things as storm drains, underdrains, catch basins, outfalls, grassed and stone lined swales, and temporary sediment control measures.
In all cases, Town staff conducts one or more inspections to confirm that all conditions of approval have been met, prior to issuance of a Certificate of Occupancy. For large or complex projects, Williston charges engineering development fees which are used to hire consultants both to review development plans prior to approval and to perform on-site inspections during construction
As indicated above, the Town has already undertaken a preliminary review of its ordinances and regulations as they relate to construction stormwater management and erosion control. In addition, the Allen Brook TMDL study, currently underway, includes a review of local regulations and suggestions for improvement. While the Town's work to date is notable, it does not address all aspects of construction site stormwater and erosion control that are currently seen as problematic. In particular, the current regulations do not address minimization of sediment loads at the source, or of removal of sedimentation before discharge. The Town anticipates a significant upgrade of its regulations in the near future.
It must be noted that the Watershed Improvement Plans (WIPs) for Muddy Brook and Allen Brook have not yet been issued by ANR. When they are issued, they may contain additional issues to be considered when revising the Town’s ordinances and regulations.
·
Best Management Practices: The following have been identified as best
management practices for the Town to undertake to achieve this minimum control
measure. It is felt to be premature to
attempt to specify best management practices to be applied to individual sites
at this time. When Town ordinances and
other regulations are upgrades, such site-specific approaches will be included.
1. The Town will include in its application packets for Site Plan Approval and Subdivision Approval a form on which the applicant must delineate the area or areas on the development site to be disturbed by construction activities, and to estimate the size(s) of such areas. Town staff will review this information and if it is judged to be satisfactory, forward copies of the forms to the Secretary of ANR or a designated recipient.
2. Since Town staff already conducts one or more site inspections, staff will be instructed to be on the look out for evidence that stormwater and erosion control measures are either not installed properly or are not being maintained. When such evidence (eroding soils, turbid waters, or other indicators) is seen staff will be instructed to notify the Secretary of ANR or a designated representative.
3. As noted, the Town has already undertaken a review of policies, ordinances and other regulations as they pertain to effective stormwater and erosion control on construction sites. This effort will be expanded to include the Public Works Specifications as they relate to Town construction activities.
4. The Town will amend the Site Plan Review section of its Zoning Ordinance and the Storm Water Section of its Subdivision Regulations to specifically address stormwater and erosion control on construction sites. These regulations will incorporate best site specific management practices described in manuals published by the Vermont Agency of Natural Resources, recommendations from the Allen Brook TMDL study, the Muddy Brook and Allen Brook WIPs, as well as other sources. Specific issues to be addressed may include, but are not limited to:
· Diversion of surface water entering the site up-slope from construction areas so that the water bypasses the construction areas via grassed or vegetated swales;
· Limitation of the area that can be exposed at any one time;
· Collection of sediments down-slope of the construction prior to discharge to receiving waters or adjoining property;
· Mulching and seeding of exposed areas as soon as work is completed;
· Protection of topsoil (or other material) stockpiles by mulching and seeding and/or silt fencing and sedimentation collection downstream prior to discharge;
· Check dams and sediment traps in swales;
· Use of construction entrances to collect sediment from construction vehicles before they leave the site;
· Systematic recovery of any sedimentary materials that are transported off the site (onto roads or adjoining property) before it can be washed into stormwater facilities. Material must be collected via vacuum trucks rather than simply being swept off the pavement into adjacent areas.
In addition, the regulations will be amended to address the removal and disposal of construction wastes.
5. The Town will upgrade its Public Works Specifications as they apply to construction of facilities that will be come publicly owned. New provisions will specifically address erosion control measures, both during construction and afterward, and removal and disposal of construction wastes.
6. Vermont statutes (24 V.S.A., Chapter 117) set forth specific enforcement provisions for all requirements enacted as part of Zoning Regulations or Subdivision Regulations. The Town Zoning Administrator is responsible for identifying violations and initiating enforcement activities. Members of the public may report any concerns or observations regarding violations to the Zoning Administrator, who will investigate and proceed with enforcement if appropriate. Enforcement decisions of the Zoning Administrator may be appealed first to the Town Development Review Board, and secondly to the Vermont Environmental Court. Fines for violations are specified in the statute.
7. To effectively implement the control measures described above, the Town will augment its current inspection practice to ensure periodic inspection of all construction sites. The Town will explore alternative ways of staffing these inspection efforts. It may be appropriate to combine this with inspection activities required under the Post-Construction Runoff Control Minimum Control Measure.
·
Measurable Goals: The following measurable
goals will serve as benchmarks for the effective implementation of the above
Best Management Practices.
1. Identification of construction sites: By the end of year 1 of the permit period the Town will have incorporated into its application packets for Site Plan Approval and Subdivision Approval a form on which the applicant must delineate the area or areas on the development site to be disturbed by construction activities, and to estimate the size(s) of such areas. Town staff will review this information and if it is judged to be satisfactory, forward copies of the forms to the Secretary of ANR or a designated recipient. The notification process will continue through the five year permit period.
2. Notification of stormwater and erosion problems: By the end of year 1 of the permit period the Town will have instructed its staff to be aware of signs of stormwater and erosion control problems or evidence of non-compliance with applicable permits, and to notify the Secretary of ANR (or a designated recipient) of such observations. The notification will continue through the five year permit period.
3. Review of Policies: By the end of year 1 of the permit period the town will have completed the review of its planning, zoning, subdivision and other regulations and specifications for effectiveness in controlling pollutants and excessive discharges into the stormwater system.
4. Ordinances: By the end of year 2 of the permit period the Town will have adopted amendments to its Zoning Ordinance and Subdivision Regulations to incorporate requirements for controlling erosion and sediment, and removal/disposal of construction waste, on all construction sites subject to local regulations (not just those meeting the one acre and five acre thresholds of the General Permits). Implementation and enforcement of these regulations will continue through the five year permit period.
5. Public Works specifications: By the end of year 3 the Town will have amended its Public Works Standards to incorporate requirements for controlling erosion and sediment, and removal/disposal of construction waste, on public facility construction sites.
6. Inspection: In year 3 the Town will formalize the periodic inspection of construction sites to ensure the implementation of the best management practices set forth in the ordinances and Public works Standards. Integral to this inspection activity will be a procedure for recording all inspections, violations noted, follow up, and enforcement actions needed. This procedure can also be used to respond to information provided by the general public. This enforcement effort will continue through the five year permit period.
Minimum Control Measure 5
- Post Construction Runoff Control
· General Discussion: Ultimately, long term impacts on surface water quality will result from stormwater management practices that carry on long after construction of developments is complete. These "post construction" control measures are designed into development projects to address three specific aspects of stormwater runoff: a)The overall quantity of runoff generated by the development site; b)The velocity at which the runoff is discharged from the site; and c) The quality of the runoff. To date the water quality studies of impaired waters in Williston indicate that water quality concerns are suspended solids (sediments) and nutrients (primarily phosphorous) that attach to the sediments.
Under the Federal Clean Water Act, the Vermont Agency of Natural Resources (ANR) has been given stormwater runoff control jurisdiction over large development projects. Up until 2002, large was defined as any project involving five acres or more of disturbed soil. Beginning in 2002, that threshold was reduced to projects involving one acre or more of disturbed soil. In addition, Vermont legislation has given the ANR jurisdiction over construction projects that result in more than one acre of impervious surface. Vermont has adopted laws and rules that establish design requirements for post construction runoff controls. These are set forth in "THE VERMONT STORMWATER MANAGEMENT MANUAL FOR WATERSHED IMPROVEMENT PERMITS" (The Manual).
Historically, the ANR has exercised its jurisdiction through the issuance of Discharge Permits, and approximately 100 such permits have been issued for development in the Town of Williston.
Issuing permits and approvals carries with it an enforcement responsibility. Having said that, it is recognized that enforcing previously issued permits may be problematic. In some cases developers that obtained the permit are gone. In other cases the permits transferred to new owners or homeowners associations that were unaware of their responsibilities. In still other cases the actual permittees may be unclear. The Town will certainly cooperate and assist the ANR in identifying and meeting its enforcement responsibilities.
As noted above, small MS4s must develop Stormwater Management Plans which address six Minimal Control Measures, and must seek coverage under a General Permit for MS4s issued by ANR. The General Permit for MS4s issued by the Secretary of the Agency for Natural Resources (ANR) requires that all small MS4s to develop, implement and enforce a program to address post construction runoff. Such a program must include the following elements:
1. Develop, implement and enforce a program to reduce pollutants in storm water runoff from construction projects that result in land disturbance of less than one acre and that have less than one acre of impervious surface.
2. Assist the Secretary in regulating construction activities resulting in more than one acre of disturbed land and one acre or more of impervious surface.
3. Review of the Town's existing policies (planning, zoning, subdivision) and ordinances regarding their effectiveness in managing post construction related erosion and sediment and controlling waste, and with the requirements of the General Permits for large and small construction sites and the Secretary’s rules for projects resulting in one or more acres of impervious surface.
4. Establishment of a procedure for identifying construction activities meeting the one acre and five acre thresholds, and for reporting such activities to the Secretary of ANR.
5. Adopt a storm water management ordinance that addresses post construction runoff issues for development that results in greater than one acre of disturbed surface and less than one acre of impervious surface. Said ordinance must minimize water quality impacts, utilize structural and non-structural Best Management Practices (BMPs), and ensure adequate long term operation and maintenance of the BMPs.
6. Establishing procedures to assist the Secretary of ANR in inspecting development projects that disturb more acre or more of area and have more than one acre of impervious surface, by reporting such signs of con-compliance such as eroding soil, turbid waters, structural deficiencies, catch basins in need of cleaning, and other readily observable problems.
· The Williston Context: In recent years Williston has been taking steps to improve the quality of stormwater runoff within its boundaries. Most notably, the Town has incorporated a stream buffer provision into its Zoning Regulations. These provisions apply to the major named streams that traverse the Town and to a set of mapped tributary streams that feed into the named streams. The above referenced Allen Brook TMDL study has developed some suggestions on how the Town's buffer provisions can be improved, and the Town certainly intends to consider those suggestions in the near future.
Traditionally, the Town has relied on issuance of State Discharge Permits as evidence of an adequate stormwater management plan. This, however, only applies to large developments. Recently the Town has become more aggressive in asking applicants to show that the rate of discharge (cubic feet per minute) of stormwater after development will not exceed that prior to development for the 1, 2, 10 and 25 year storm events. In addition, the revised Subdivision Regulations address stormwater management in several specific places. Sub-Section 1010-D prohibits disturbance of natural drainage ways. Sub-Section 1010-E addresses erosion and sediment control. Finally, Section 1080 addresses storm drainage and includes provisions related to minimization of runoff, removal of surface water, sizing of facilities to accommodate upstream development, and responsibility for downstream drainage. These were important first steps, but current research suggests additional steps that can be taken.
As noted under Minimum Control Measure 4, Williston has already completed a a preliminary review of its Planning, Zoning Ordinance, Subdivision Regulations, and Public Works Standards relative to effective storm water management. In addition, the Allen Brook TMDL study, currently underway, includes a review of local regulations and suggestions for improvement. This review will be augmented, as described below.
Williston is in a unique position in that it is consciously attempting to create a new major commercial center in the form of a dense downtown. This form of concentrated development necessarily requires a high percentage of impervious coverage. This, in turn has the potential to result in higher rates of runoff and lower rates of stormwater infiltration. Even though this commercial center constitutes a small portion of the Town's over all land area, much of it is located within the watershed of a tributary of the Muddy Brook, a waterway identified as impaired. Due to Williston’s planned development patterns, implementation of many of the control practices described in The Manual poses significant challenges
Williston proposes to develop two approaches to post construction runoff control, both of which will be incorporated into its Site Plan and Subdivision Regulations. One approach will apply throughout the Town except for the Commercial Center. In these areas, all developments, regardless of size, will be required to satisfy the requirements of the state Stormwater Management Rules and The Manual. The second approach will apply only to the zoning districts in the concentrated commercial center. The Town will strive to identify stormwater management practices more common in urban areas that meet the objectives of the State Rules and The Manual, but which are not typically found in Vermont. It is much too early to say what these approaches will be, but is clear that the Town will have to work very closely with ANR staff to ensure that Williston's proposed regulations satisfy state requirements.
As noted above, the Watershed Improvement Plans (WIPs) for Muddy Brook and Allen Brook have not yet been issued by ANR. When they are issued, they may contain additional issues to be considered when revising the Town’s ordinances and regulations.
· Best Management Practices: Williston has identified the following Best Management Practices for achieving the objective or developing, implementing and enforcing a program to reduce pollutants in storm water runoff to the Maximum Extent Practicable (MEP).
·
Measurable Goals: The following Measurable Goals will serve as benchmarks for
the effective implementation of the above Best Management Practices.
a. require all developments in the dense commercial center to implement the identified stormwater management techniques in order to meet the State's Stormwater Rules,
b. require all developments not in the dense commercial center to design and install stormwater management practices as set forth in The Manual, and
c. require all developments to include a stormwater maintenance agreement and a vehicle for its implementation.
Minimum Control Measure 6
- Pollution Prevention/Good Housekeeping for Municipal Operations:
The General Permit for MS4s issued by the Secretary of the Agency for Natural Resources (ANR) requires that all small MS4s have an operation and maintenance program for preventing or reducing pollutant runoff form municipal operations, including, at a minimum: new construction and land disturbance, maintenance of fleet and buildings, parks, open space, and storm water systems. This must include the following:
· A training component, maintenance schedules, and inspection procedures for long term structural controls; and
· A list of industrial facilities owned or operated by the municipality and demonstration that it is in compliance with the relevant General Permit for Storm Water Discharges.
The General Permit contains a provision that participation in the ANR’s Municipal Compliance Assistance Program or the EPA’s self-audit initiative will be sufficient to demonstrate compliance with this Minimum Control Measure. Williston intends to pursue this approach.
1. The Town is participating in ANR’s Municipal Compliance Assistance Program. A compliance inspection was completed on January 7, 2003. A copy of the report is included as Attachment B. The report calls for only minor modifications in order to qualify for full compliance. It is the Town’s intention to comply with the findings of the inspection, and to maintain compliance throughout the permit period.
2. The salt storage pile is fully enclosed, thus eliminating exposure and preventing discharge of salt contaminated runoff.
3. Vehicle washing facilities are inside the building. The floor drains are served by an oil/grease and sediment separator, and are connected to the Town’s waste water treatment system, thus eliminating discharges from this activity.
4. An asphalt surface was recently installed for loading winter maintenance materials (salt and sand), allowing Public Works personnel to pick up spilled materials during loading operations.
5. Recently completed improvements direct stormwater away from salt and sand storage and loading areas, further preventing sediments and pollutants from traveling off-site.
6. The Town has initiated a tracking system regarding the disposal of all hazardous wastes generated by these facilities.
7. All municipal equipment (light duty trucks, dump trucks, heavy equipment, etc.) is serviced at the Public Works garages. All waste oil is barreled for pick up by a waste oil burning company. New oils are stored at the Public Works garages in delineated containment areas. Floor drains in these areas will have absorbent pads placed in them to capture minor drips and leaks. Heavy equipment and fuel stations are equipped with spill kits for pollution clean-up.
8. Williston owns and maintains approximately 1,300 catch basin structures. Annual inspections by Public Works personnel determine the schedule for removing sediments and pollutants from these structures, along with structure maintenance. On average, approximately 1/3 of the structures are cleaned each year, and all maintenance activities are recorded on the Department’s mapping and maintenance log. Approximately 12 cubic yards of material are removed from catch basins each year.
9. Twice each year (Spring and Fall) all streets (approximately 17 miles) with curbs and closed drainage systems are swept. This generates approximately 14 cubic yards of material annually.
10. Materials removed during street sweeping and from catch basin cleaning are disposed at an approved fill site.
11. Construction projects undertaken by the Public Works Department are designed by a Professional Engineer, and include properly designed erosion control devices. Public Works personnel install the erosion control devises as designed. All erosion control devices are maintained throughout the project on a daily basis. All land disturbances within construction sites are stabilized as soon as practicable by such methods as seed, mulch, erosion blankets, silt fences or plantings.
12. Employees assigned to Public Works facilities have an average of ten years of service and have been trained in Public Works functions related to good housekeeping and polluting prevention techniques.
13. Training will be continued periodically with special emphasis on the proper handling of hazardous materials.
The Town is taking all practicable steps to eliminate exposure to stormwater and will apply for a certification of no exposure as described in the Multi-Sector General Permit.
1. The Town will obtain a Certification of No Exposure for its Town Garage Facility, and on the basis of that certification will apply for coverage under the ANR’s Multi-Sector General Permit for Stormwater Discharges Associated with Industrial Activity (General Permit 3-9003).
2. The Town will implement recommended improvements resulting from the recent Municipal Compliance inspection, and will maintain compliance throughout the permit period.
3. The Town will continue its on-going training program for Public Works personnel related to stormwater management and handling of hazardous materials.
1. In year 1 of the permit period the Town will seek coverage for its Town Garage facility under ANR’s Multi-Sector General Permit for Stormnwater Discharges Associated with Industrial Activity (General Permit 3-9003). The Town will maintain this coverage throughout the permit period.
2. In year 1 of the permit period the Town will apply for a Certification of No Exposure for the Town Garage facility. The Town will maintain this certification throughout the permit period.
3. In year 1 of the permit period the Town will implement recommended improvements resulting from the recent Municipal Compliance inspection. The Town will maintain compliance throughout the permit period.
4. In year 1 the Town will obtain training for Public Works staff, and other staff as appropriate, training in recognizing signs of stormwater management/erosion control failures, as described in minimum control measures 4 and 5.
5. In subsequent years the Town intends to arrange for at least one training program for Public Works staff related to stormwater management, erosion control, and/or handling of hazardous materials, providing that such training programs are available.
IV.
CONCLUSION:
Williston has and will continue to take significant steps to minimize pollutants entering the State’s waterways via stormwater runoff. The comprehensive Stormwater Management Plan described in the previous section presented steps to be taken in the immediate future to comply with the Phase II stormwater requirements of the Clean Water Act of 1972, and interpreted and administered by the Vermont Agency for Natural Resources. The following table summarizes those steps on a year-by-year basis.
Time Table for Achieving Measurable
Goals
Attachment
A
Memorandum Of Understanding Between
Participating MS4s Regarding a Regional Approach to Public Education on
Stormwater Management
Attachment B
Report of January 7, 2003 Municipal Compliance
Assistance Program
On-Site Review