Sudbury Wetlands Administration
 Bylaw Regulations

Revised: July 2001

1.     PURPOSE

The purpose of these regulations is to aid in the consistent and effective implementation of the Sudbury Wetlands Administration Bylaw by way of further definition; explanation and specification; and illustration and example of the Bylaw’s provisions. These regulations are intended to clarify but not expand, extend, modify, or replace any provision of the Sudbury Wetlands Administration Bylaw.


2.1 Wetland Resources

Wetland resources protected by this bylaw include:

2.1.1 Any creek, stream (intermittent or perennial), river, pond, lake, or vernal pool

2.1.2 Isolated and bordering land subject to flooding.

2.1.3 Any bank, freshwater wetland, marsh, swamp, wet meadow, or bog bordering on or having a hydraulic connection to any of the resources listed in 2.1.1 or 2.1.2.

2.1.4 Land under any of the bodies listed above


2.2 Presumption of Vernal Pool Habitat

The Bylaw presumes vernal pool habitat exists if a wetland’s physical characteristics conform with those defined for vernal pools in Section 9 (Definitions) of the Bylaw:

"The term "vernal pool" shall include, in addition to that already defined under the Wetlands Protection Act, G.L. Ch. 131, §40 and Regulations thereunder, 310 CMR 10.00, any confined basin or depression not occurring in existing lawns, gardens, landscaped areas, or driveways which, at least in most years, holds water for a minimum of two continuous months during the spring and/or summer, contains at least 200 cubic feet of water at some time during most years, is free of adult predatory fish populations, and provides essential breeding and rearing habitat functions for amphibian, reptile, or other vernal pool community species, regardless of whether the site has been certified by the Massachusetts Division of Wildlife and Fisheries."

This presumptive definition for vernal pools is based on systematic field observations in the Town of Sudbury by the Sudbury Conservation Commission showing that virtually all basins that possess the above characteristics actually host breeding vernal species. Undoubtedly this is a particular consequence of Sudbury’s semi-rural character and enduring woodlands and wetlands.

The presumption of vernal pool habitat may be overcome, however, with the presentation of credible evidence which in the judgment of the Conservation Commission demonstrates that the wetland does not provide, or cannot provide, vernal pool habitat functions.

2.2.1 Demonstrating that a Ponding Area Is Not a Vernal Pool

For the purposes of overcoming the presumption of vernal pool habitat the Commission will consider: Evidence that the ponding area does not hold water for at least two continuous months in most years. As a rule of thumb the term "most years" shall mean three out of five consecutive years. Evidence that vernal pool species do not breed or have not bred in the ponding area. The Conservation Commission shall provide explicit guidelines for this evidence. Evidence that the ponding area could not be a viable breeding site for vernal pool species due to incompatible physical, chemical, biological, or other persistent conditions at the site in most years. Such evidence could include, without limitation, several months of pH and dissolved oxygen measurements yielding values incompatible with amphibian or reptile breeding.

2.2.2 Timing of Evidence Collection.

Many of the indicators of vernal pool habitat are seasonal. For example. certain salamander egg clusters are only found between late March and late May. Wood frog chorusing only occurs between late March and May, and then only at night. Consequently, failure to find evidence of breeding must be tied explicitly to those periods during which the evidence is most likely to be available.

Accordingly, in the case of challenges to the presumption of vernal pool habitat the Conservation Commission may require that the determination be postponed until the appropriate time period consistent with the evidence being presented. The Commission may also require its own site visits as necessary to confirm the evidence.

2.3  Intermittent Streams

Intermittent streams are important for storm damage prevention, flood control, ground water protection, wildlife habitat, and recreation values. During spring, summer, and fall these streams disperse snow melt and storm runoff across the landscape thereby preventing dangerous volumes and flows from spilling over roadways and property. This broad dispersal also allows for larger volumes of water to infiltrate into the ground, recharging groundwater supplies.

Intermittent streams are an essential source of food and water for wildlife, and are often the only source of water in higher elevation areas of town. The moist soils that border intermittent streams are significantly richer in herbs and flowering/fruiting plants – the base trophic level of food -- than surrounding upland areas.

During all seasons, but especially in winter and spring, intermittent streams act as essential corridors for animal movement when food is scarce. Some animals, such as pickerel frogs and eastern spotted newts, rely heavily on intermittent streams for movement.

For these reasons the upland areas surrounding intermittent streams are heavily utilized by wildlife for living space, breeding, feeding, migrating, dispersal, and security.

Accordingly, this Bylaw protects intermittent streams of all forms (Regulations Section 9.9) and the adjacent upland resource within 100 feet of those streams.  For the purposes of this Bylaw an intermittent stream is that segment of a flowing watercourse that regularly experiences naturally occurring sporadic flow interruptions such that it does not have a continuous sheet of surface water for five consecutive days or more annually.

The Conservation Commission recognizes two types of intermittent stream:

  • Type I: Stream segments in which continuous standing water disappears for at least five (5) but not more than thirty (30) consecutive days annually.

  • Type II: Streams in which continuous standing water disappears for more than thirty (30) consecutive days annually.

For the 100-foot adjacent upland resource area for Type I intermittent streams the Conservation Commission may, based on the specific functions and values of the resource, use protection guidelines adopted for the 100-foot Riverfront area for a perennial stream.

[See section 2.4 Perennial Streams, below, for specific evidence requirements to document intermittent streams.]

2.4 Perennial Streams

Under this Bylaw all flowing watercourses shall be considered to be perennial streams unless a preponderance of evidence deemed acceptable by the Conservation Commission rebutting this presumption is presented.  Information necessary to overcoming this presumption includes, but is not limited to, direct observation and documentation of the:
  • The absence of a continuous sheet of surface water throughout the watercourse, or relevant segment, for a minimum of five consecutive days annually in most years (excluding periods when local drought or other conditions abnormally lowering the water table are known to exist, or due to water withdrawals) as witnessed by a member of the Conservation Commission or its staff; which shall be considered definitive evidence in overcoming the presumption of perennial status.

Other information that may be relevant to overcoming the presumption of perennial stream status for a watercourse or a segment of that watercourse includes, but is not limited to, direct observation and documentation of:

  • Absence of gravel, mineral, and riffle substrate;
  • Absence of a clearly defined flow channel;
  • Absence of bank undercutting;
  • Presence of established non-aquatic plants in the flow path (i.e., plants that are
     unable to grow in continuously submerged conditions);
  • Absence of a continuous sheet of surface water in the stream channel or relevant segment at a time when Conservation Commission designated perennial streams of comparable characteristics are flowing, as witnessed by a member of the Conservation Commission or its staff.

The Conservation Commission will also consider estimates from modeling studies of surface water and ground water hydrology in the relevant watershed.  However, such information will only be considered as evidence in conjunction with the observable indicators noted above. 

Observational evidence shall, in all instances, take precedence over estimates, calculations, and other inferential evidence. 

The Conservation Commission shall consider all of the evidence available together, judging the validity and reliability of the information, and base its determination on the preponderance of acceptable evidence.


3.1 Exceptions for Existing Single Family Residential Structures

As stipulated in Section 3 of the Bylaw:

"The application and permit required by the Bylaw shall not be required for maintaining, repairing, replacing, or enlarging an existing and lawfully located single-family residential structure or appurtenance thereto unless said filing is otherwise required by state or federal law."

The intent of this partial exemption is to allow owners of single family homes, built prior to the Bylaw, to continue to live and work according to the rules, regulations, and assumptions under which they originally purchased their homes.

Any property owner, irrespective of when their property was developed, has the legal right to challenge any provision of the Bylaw at any time. However those whose properties were developed prior to the Bylaw might face an undue burden under the Bylaw because the configuration of their lot and associated development were determined without prior knowledge of the Bylaw. In contrast, single family residences built after the Bylaw could be appropriately planned around restrictions in order to minimize constraints.

3.1.1 Definition and Application of the Term "Existing"

The term "existing" refers to structures placed in service prior to July 27, 1994, and refers to both the single family structure and any appurtenance claiming exemption.

Therefore, the application and permit required by this Bylaw shall apply to work associated with entirely new structures (those that are not replacing antecedents) placed in service on or after July 27, 1994, whether or not they would be considered appurtenant.

In those instances where a state or federal filing is required for projects associated with existing single family residences, the full application and permit required by the Bylaw does apply.

The above notwithstanding there are a number of other special rules and exemptions in the Bylaw pertaining to single family residences that existed prior to July 27, 1994, such as delineation of certain adjacent upland resources, that might still apply.

3.2 Expansion of Agricultural Lands

Agriculture is one of the interests and values protected by the Sudbury Wetlands Administration Bylaw. Accordingly the Bylaw (Section 3) exempts certain work on lands already in agriculture from permitting as long as that work meets approved performance standards under the Bylaw.

Expansion of agricultural activities onto lands not previously in agriculture and within the jurisdiction of the Commission does require a permit. In protecting agricultural values and interests under the Bylaw the Commission may require as one of its conditions for approval that the land be placed under a deed restriction for at least 10 years limiting use of that land to agriculture, especially if that land was previously in an undisturbed state.

3.3 Farm & Fire Ponds

Historically farm and fire ponds have served as vernal pools across the New England landscape. Some of Sudbury’s most important salamander breeding sites, including those of rare species, are abandoned and existing farm and fire ponds. Accordingly, stocking of farm and fire ponds with fish shall not permitted except in those cases where the Commission determines that the pond does not currently, and in the future will not likely, serve vernal pool functions.


4.1  Timeframes for Submission of Documentation

All documentation -- including, plans, maps, tables, charts, reports, etc. -- to be considered as part of a permit filing by the applicant must be submitted to the Conservation Commission no later than four business days prior to the scheduled public hearing, or its continuation. This is the minimum time needed to allow the Commission and staff to properly review, analyze, and check the information provided.  Documentation submitted with fewer than the minimum four business days for review may be excluded from consideration at the scheduled hearing and held for discussion at a subsequently scheduled meeting.

4.2   Wetland Resource Designations on Plans

All plans submitted to the Conservation Commission for a permit under Section 4. of the Bylaw  must show all wetland resources on the property and within 100 feet of the property lines (200 feet in the case of perennial streams), regardless of whether or not the proposed work is expected to occur within the jurisdictional areas associated with the resource.

In those instances where the project is part of a subdivision, a plan must be submitted to the Conservation Commission showing all wetland resources located within the subdivision boundaries and within 100 feet of those boundaries (200 feet in the case of perennial streams).

Failure to provide this information, or providing erroneous or false information, shall be grounds for denying, suspending, or revoking the permit as outlined in Section 7. of this Bylaw.

4.3  Notice of Resource Area Delineation

A Notice of Resource Areas Deliniation (NRAD) or an abbreviated NRAD must include all potential wetland and adjacent upland resource areas under a single comprehensive delineation.

4.4 Documentation for Violations

All filings associated with a Notice of Violation shall include an accurate plan that clearly and explicitly shows all jurisdictional resource areas on the property and the area(s) of disturbance including an explicit tabulation of the size of the disturbance.   The Conservation Commission may require a surveyed/engineering plan.

4.5 Single Minor Project

For the purposes of fee determination work to remove debris and hazardous materials from wetlands, and wetland restoration projects, and similar projects for improving the natural capacity of a wetland resource to protect or enhance wetland values shall be considered a single minor project.

4.6 Resource Restoration and Enhancement Projects

Wetland and/or adjacent upland resource restoration and enhancement projects that (1) are not the result of a Notice of Violation, and (2) are not part of a mitigation project tied to other work covered under another Notice of Intent, and (3) do not require a filing under Massachusetts Wetlands Protection Act or received a negative determination of applicability, may file an abbreviated Notice of Intent for Resource Restoration & Enhancement with the Conservation Commission.

  • The conservation agent, acting at the direction of the Conservation Commission, shall determine whether a project qualifies for this special NOI.
  • A special Notice of Intent for Resource Restoration & Enhancement application shall be used for qualifying projects.
  • All standard bylaw NOI requirements and procedures, such as abutter notification, hearing publication, and final issuance of a certificate of compliance, shall be followed.
  • The fee shall be $25 for a single minor project, as noted in these regulations Section 4.4.

4.7 Subdivision Roadway Fees

For the purposes of fee determination the term roadways in the case of subdivisions shall include all common and private driveways associated with new lot construction. Therefore driveway sidelines that fall within the adjacent upland resource shall be added to the overall roadway sideline calculation pertinent to fees for roadway construction in the adjacent upland resource.

In those instances where driveways for new lots are not included in the subdivision application, the pertinent driveway sideline charge shall be imposed when the specific lot plan is submitted. Where the $500 base fee for roadways has already been paid as part of the subdivision application that fee shall also cover the base fee for subsequent driveway plans in the subdivision.

4.8   Drainage Structure Fees

The $500 fee will apply to each independent or each network of hydraulically connected detention basins, retention basins, catch basins, or combination of swales, infiltration pits, and dissipation fields that;

  • are located in whole or in part in a adjacent upland resource or resource area, and/or
  • discharges into a adjacent upland resource or resource area, directly or indirectly; and
  • requires substantial review of pre and post drainage calculations.

Swales, infiltration pits, and dissipation fields networked with detention, retention, or catch basins will not be assessed an additional fee.

The above notwithstanding, In no case shall the fee for projects involving drainage structures be less than $500.

4.9  Disturbed Adjacent upland resources for Commercial & Industrial Projects

The fee of $0.50 per square foot of disturbed adjacent upland resource listed under Section 4 (f) of the Bylaw shall pertain to areas not previously or presently under industrial or commercial use.




7.1 Performance Standards & Design Criteria for Adjacent Upland Resources

As stated in the Bylaw, Section 7 Permits and Conditions lands within 100 feet of wetlands resource areas (25 feet in the case of isolated land subject to flooding):

"...are presumed important to the protection of these resources because activities undertaken in close proximity to wetlands and other resources have a high likelihood of adverse impact upon the wetland or other resource, either immediately, as a consequence of construction, or over time, as a consequence of daily operation or existence of the activities. These adverse impacts from construction and use can include, without limitation, erosion, siltation, loss of groundwater recharge, poor water quality, and harm to wildlife habitat.

The Commission therefore may require that the applicant maintain a strip of continuous, undisturbed vegetative cover in part or all of the 100-foot area and set other conditions on this area, unless the applicant provides evidence deemed sufficient by the Commission that the area or part of it may be disturbed without harm to the values protected by the law."

In some circumstances some types of activities, when properly conditioned, may be acceptable in adjacent upland resource areas. Under other circumstances even minimal adjacent upland resource disturbance may have serious harmful effects on resource area values and functions. When the presumption of significance is questioned the actual determination of impact must be made on a project-and site specific basis. And in this respect the actual impact of proposed adjacent upland resource work or activities on wetland values and functions can often be reduced substantially, and thus made permissible, when appropriate conditions are imposed.

Therefore the traditional approach of "all or nothing" adjacent upland resource restrictions unnecessarily creates conflicts between property use and resource protection. Accordingly the Bylaw gives the Conservation Commission broad discretion to permit, condition, and prohibit work within the adjacent upland resource as the specific situation warrants

Therefore the Conservation Commission shall consider proposals for work in the adjacent upland resource in terms of four broad forms of disturbance areas. This approach is intended to allow maximum flexibility for property use while maintaining adequate levels of resource protection.

7.1.1 No Disturbance Area

This is an area in which virtually no activities or work, other than passive passage, are permitted. No vegetation may be disturbed, leaf litter and debris remains in place, etc. The no disturbance area should remain unchanged from its pre-project state.

7.1.2 Temporary Disturbance Area.

This is an area in the adjacent upland resource where temporary disturbance for a limited period of time is permitted, such as for regrading or travel by heavy machinery. Once the activity is completed, however, the area will be allowed to return to natural vegetation and function. Any subsequent disturbance or activity shall require a new filing.

The Conservation Commission shall establish specific time frames and conditions for allowing temporary disturbances, as well as setting criteria for assessing the successful return of the adjacent upland resource to natural functions.

7.1.3 Limited Disturbance Area

This is an area in the adjacent upland resource where a limited set of activities and work is permitted in perpetuity. For example understory clearing of poison ivy might be allowed, but no clearing of overstory and no planting of lawn. Limited (sustainable) harvesting of wood, composting of brush, and storing firewood are other examples of limited activities that might be allowed.

7.1.4 Permanent Disturbance Area.

This is an area in the adjacent upland resource in which most, if not all, legal activities and permanent disturbances are permitted. Houses, porches, driveways, gardens, and lawns in the adjacent upland resource represent permanent disturbance areas.

Nevertheless, within the context of permanent disturbance the Conservation Commission may set specific conditions prohibiting or restricting those forms of work and activities in the adjacent upland resource deemed potentially harmful to the resource area values, such as the use of herbicides and pesticides, use of interceptor drains, or installation of in-ground sprinkler systems for irrigating areas in the adjacent upland resource.

7.2 Considerations in Setting Disturbance Restrictions.

A growing body of research evidence suggests that even "no disturbance" areas reaching 100 feet from wetlands may be insufficient to protect many important wetland resource characteristics and values. Problems of nutrient runoff, water pollution, siltation, erosion, vegetation change, and habitat destruction are greatly exacerbated by activities within 100 feet of wetlands. Thus, in general work and activity within 100 feet of wetlands should be avoided and discouraged and reasonable alternatives pursued.

Accordingly, the Conservation Commission shall begin with the presumption that lands within the adjacent upland resource of a resource are best left in an undisturbed and natural state. [Note: The Bylaw contains a number of exemptions for single family residences existing prior to July 27, 1994].

However the Commission shall designate areas of the adjacent upland resource to be suitable for temporary, limited, or permanent disturbance as appropriate when the applicant can demonstrate to the Commission’s satisfaction that the proposed work or activity will not affect wetland values singularly or cumulatively and that reasonable alternatives to the proposed work or activity do not exist.

In considering designation of adjacent upland resource disturbance areas, the types of work and activities allowable, and conditions to apply, the Conservation Commission shall consider:

7.2.1 Values and Functions of the Resource Area

The quantity and quality of resource values and functions should be considered explicitly in placing conditions on adjacent upland resource work. Some isolated land subject to flooding, for example, may serve for temporary flood storage only. Minimal adjacent upland resource restrictions within several feet of the resource might be necessary only to prevent erosion.

Other isolated land subject to flooding might provide vernal pool habitat. It might also provide important flood storage capacity and intersect ground water. In this instance far stronger adjacent upland resource restrictions would be appropriate because a larger number of functions are involved and some functions, such as habitat, are more sensitive to adjacent upland resource activity and require greater protection. If rare or endangered species, such as blue spotted salamanders, were found at the site then still greater levels of restrictions would be appropriate.

7.2.2 Pre-Project Characteristics of the Site

Ground slope, soil conditions, vegetation, and prior disturbance are just a few of the site specific characteristics that shall be considered in setting conditions for work in the adjacent upland resource.

For example land that slopes toward a wetland demands greater restrictions on work and activity and larger no-disturbance distances to prevent pollution and silt from stormwater runoff from harming wetlands values. Larger slopes imply greater restrictions.

7.2.3 Wildlife Habitat and Rare Species

The near-upland areas around wetland resources often play important roles in determining and maintaining the wildlife habitat values of associated wetlands. While it is common to think of the protective or "buffering" value of adjacent upland resources in terms of area undisturbed, habitat values may be equally affected by the configuration of the adjacent upland resource perimeter, the inclusion or exclusion of specific topographical and ecological features (such as an abutting sandy knoll or tree canopy), etc.

Therefore where significant wildlife habitat values and functions are present delineation of non-disturbance areas within the adjacent upland resource shall, as is reasonable, minimize the length of perimeter to area left undisturbed, exclude fingers, islands, or other projections or indentations of the non-disturbance zone, and in general avoid delineating oddly shaped non-disturbed areas. The Commission shall give special attention to inclusion inside the no disturbance area of those topographical and ecological features that it deems important for maintaining the wildlife habitat value of the resource.

The potential presence of rare or endangered species and their specific sensitivity to adjacent upland resource activity shall be considered in determining adjacent upland resource restrictions. Evidence of the presence of such species or evidence of likely habitat shall be considered by the Conservation Commission. Prior designation of rare or endangered species habitat by the Division of Fisheries and Wildlife Natural Heritage Program is not necessary.

The Commission may consult with the Division of Fisheries and Wildlife Natural Heritage Program or other authorities as it deems necessary for guidance and recommendations.

7.2.4 No Significant Adverse Impact On Wildlife Habitat

Wildlife habitat serves a variety of functions in support of wildlife. Food, water, breeding space, shelter, security, movement and migration space, and connections to other habitat areas are all equally important. All of these wildlife habitat functions are presumed to exist in all resource areas.

Therefore in accordance with the Bylaw’s fundamental purposes (see Section 1) no project may have a significant adverse impact -- either project-specific or cumulative -- on wildlife habitat for more than two growing seasons.

For wildlife habitat purposes, a significant adverse project-specific impact is defined as an impact caused by work in a resource area that would under reasonable assumptions (a) result in a measurable decrease in the extant wildlife populations or biological composition, structure, or richness on the site or in the vicinity exclusive of the present or future state of adjacent and nearby properties, or (b) impair, damage, destroy, or reduce in value for wildlife purposes certain specific habitat features.

Wildlife studies have shown that direct impacts from work – filling, grading, vegetation removal, construction of barriers to movement, etc. – in resource areas can severely harm wildlife populations. For example, low stone walls bisecting a resource area can prevent amphibians that live in upland areas from reaching breeding pools, marshes, and streams. Or, removal of large snags (dead trees) can virtually eliminate nesting by barred owls, pileated woodpeckers, mink, etc. Accordingly, the Commission shall prohibit the placement of fences or other barriers to wildlife movement within and between resource areas and the destruction of specific habitat features.

Examples of protected habitat features include (but are not limited to):

  • Large cavity trees

  • Turtle nesting areas

  • Existing nest trees for birds that reuse nests (e.g., great blue herons,

  • Beaver dams, dens, and lodges

  • Mink or otter dens

  • Vernal pools

  • Vertical sandy banks

  • Migration corridors that provide connectivity between wildlife habitats

  • Sphagnum hummocks and pools suitable to serve as nesting habitat
    for four-toed salamanders

But indirect impacts – the effects of human activities near wildlife habitat – can have equally harmful effects. Therefore the Commission shall take into account indirect effects on a project by project basis. So, for example, no work within resource areas shall be permitted within 100 feet of existing beaver, mink or otter dens, or within 200 feet of existing osprey or great blue heron nests.

As clearly stated in Section 1 of the Sudbury Wetlands Administration Bylaw the purpose of the Bylaw is to preserve for future generations of residents the natural resources and amenities – including wildlife – we presently enjoy in Sudbury. The Bylaw protects future values as well as current ones. Therefore, the Commission must be especially cognizant of the likely cumulative impact of work within resource areas.

For wildlife habitat purposes a significant cumulative adverse impact is defined as an impact that would under reasonable assumptions result in a measurable decrease in the extant wildlife populations or biological structure, composition, or richness on the site or in the vicinity taking into account the projected impacts of future projects that could be proposed in the vicinity with similar, comparable, or other significant impacts and disturbance.

This method for assessing cumulative impacts avoids the pitfall of placing an unreasonable burden of resource protection on subsequent applicants/projects in the vicinity while subsidizing those who are first to develop land. It allows the Commission to level the marginal impact of all proposed projects in the vicinity while ensuring appropriate protection – present and future -- of the values and interests protected by the Bylaw.

7.2.5 Projects to Enhance or Benefit Wildlife Habitat

The Conservation Commission may, as part of the permitting process, require at its discretion any project that proposes to alter the extant wildlife populations or biological composition, structure, or richness of an area as a wildlife benefit to have that plan approved by the Massachusetts Division of Fisheries and Wildlife.

7.2.6 The Character of the Work or Activities Proposed and Alternatives

The applicant shall carry the burden of proof for demonstrating to the Commission’s satisfaction that the proposed work or activities in the adjacent upland resource are necessary and that reasonable alternatives, including reducing the scale and scope of the project, do not exist.

The Commission shall consider the specific characteristics of the work proposed for immediate and cumulative impact on the wetland resource. For example, understory clearing and shrub landscaping in sensitive sections of the adjacent upland resource might be appropriate where a lawn might not due to concerns about nutrient runoff. Similarly, clearing a flat section of the adjacent upland resource to establish a vegetable garden might not threaten adjacent wetland values and functions. However, construction of a tennis court with extensive impervious surface on the same site and covering the same area might not be acceptable.

The Conservation Commission may offer suggestions and advice for altering plans and proposals to reduce impact on wetlands values and functions toward the goal of modifying the project to make it acceptable. However, the Commission is not obligated to do so and shall not be bound in its decisionmaking by any prior advice or suggestions offered to applicants.

7.3 Subdivision Roadways

The construction of impervious surfaces such as roadways in watersheds can significantly alter the quantity and quality of stormwater runoff and affect important ground water characteristics. Impervious surfaces reduce surface infiltration, potentially worsening flooding problems by increasing stormwater runoff volumes and by redirecting flows within a watershed.

The increase in surface flows from impervious surfaces may create new erosion problems where storm flows are directed and discharged.

Impervious surfaces increase the opportunities for various pollutants to mix in water flows. Roadways, for example, will retain a surface coating of petroleum and combustion-byproduct pollutants that will flush during the early stages of a storm. Roof runoff can pick up a variety of chemicals used in fertilizers, pesticides, and herbicides as it transverses lawns and landscape areas.

Impervious surfaces that direct water flows into wetlands may inundate sensitive resources and thereby destroy vital vegetative and wildlife characteristics, reduce preexisting flood storage capacity, and contaminate ground water recharge areas.

Conversely, impervious surfaces may direct traditional water flow patterns away from wetlands and thereby destroy the necessary hydrological conditions needed to maintain wetland functions and values.

Therefore, for purposes of flood control, erosion control, water quality protection, and wildlife habitat preservation the Conservation Commission shall review all roadway construction plans for impact, immediate and cumulative, on wetland functions and values. In particular, the Conservation Commission shall enforce the following general performance standards:

7.3.1 Minimize Pre-Project to Post-Project Changes in Site Hydrology

Pre-project and post-project hydrology should remain fundamentally the same as it pertains to protecting wetlands functions and values. Of course some minor degree of change in hydrology is inevitable in any engineering/construction project and within reasonable limits the Commission shall permit such variation when in its judgment such changes will not produce a significant impact of wetlands functions and values.

Erosion control may require limiting stormwater discharge volumes and velocities. Therefore the Commission may require the construction of such stormwater control structures, and specify particular engineering and design details, as it deems necessary to protect wetland resources, values, and functions.

7.3.2 Minimizing Change In Runoff Water Quality.

The physical, chemical, and biological qualities of stormwater runoff are altered by encounters with impervious surfaces, especially roadways and related structures. Increases in water temperature, reduction in pH, chemical and nutrient contamination, and transport of silt are just a few of the degrading shifts that may occur.

Where such waters are likely to contact wetland resources or adjacent upland resources the Commission shall impose conditions that in its judgment reduce undesirable water quality changes to levels that will not harm wetland functions or values, immediately or cumulatively. The Commission may require the construction of specific structures to improve stormwater runoff quality, such as wet detention basins for pollutant removal and broad riprap swales for aeration.

7.3.3 Requirements for Hydraulic Calculations

In accordance with the above, the Conservation Commission shall require as part of the application for permit complete hydrological calculations for the one, two, five, ten, twenty-five, and one-hundred year storm events. Such calculations shall include runoff from all impervious surfaces associated the project including individual lot construction; and both pre- and post-project calculations for discharge volumes, concentration times, discharge velocities, and other quantities that the Commission may require for complete information.

7.4 Site Visits

As stated in Section 7, Permits and Conditions, the Conservation Commission may deny a permit if the applicant fails to provide the information requested. "Information" in this instance includes site visits by the Commission and its staff or representatives for the purpose of directly observing pre-project and post-project conditions on the property, at seasonally appropriate times.

7.5 Replications

The history of wetland replication is mixed. Scientific reviews conclude that for the most part replications fail to reproduce the range of values — in quantity and quality — of the wetlands they ostensibly replace. In particular, difficulties in replicating proper hydrological conditions in a consistent and enduring fashion seem to be the source of the problem

Accordingly, the Conservation Commission strongly discourages any plan that requires replication. in those instances where replication is approved by the Commission the following conditions must be met:

7.5.1 The replicated wetland must be constructed in full and conditionally approved prior to construction of any structures.

7.5.2 At minimum the replicated wetland must reproduce all the values and functions of the original wetland as determined by the Conservation Commission.

Site conditions permitting the Commission may require that additional values and functions be incorporated into the replication design.

In particular, in circumstances where replacement of specific functions and values would require substantial amounts of time before being completely replicated (for example, those provided by large mature trees) the Commission may require additional compensation of area, functions, values, etc. beyond those required in other sections of the Bylaw and its regulations.

7.5.3 The area of replication must be at least twice as large as the area of the original resource that will be destroyed.

The actual area ratio of replacement shall be decided on a case-by case basis in accordance with 7.5.2.

7.5.4 In most instances the replication of wetland resource areas will result in the destruction of adjacent upland resource areas. In such instances replication of new adjacent upland resources shall follow 7.5.2 and 7.5.3.

7.5.6 The top 12" of soil from the original wetland must be transplanted with soil structure – especially lamination and density profile – intact to the replication.

This is intended to preserve plant, invertebrate, and planktonic communities of the wetland and inhibit the blossoming of invasive species.

7.5.7 Any replication or restoration work that creates a resource on abutting properties shall require an easement from the abutting property owner covering the full extension of the resource on that property prior to commencement of the work.

7.5.8 A bond shall be posted that will enable the Commission to complete the replication should the applicant fail to fulfill obligations set forth in the Order of Conditions.

Standards for the replication shall be specified and verified in terms of functions, values, and actual performance. Technical and engineering specifications used for design and construction shall be considered approximate. Criteria for acceptance and approval shall be based solely on function and performance as specified in the Order of Conditions. In other words replications will be evaluated on what they are expected to do, not how closely actual construction matched the plan.

For example, although elevations may be used for design and planning of a pond the standards shall be set in terms of volume and depth of water over the course of a year. In vernal pool replication the pool must be capable of sustaining full development of vernal pool species, regardless of design elevations or siting.

Replications that do not properly perform the approved functions and values as specified in the order of conditions will not be deemed acceptable no matter how closely they adhere to approved engineered plans.

The Commission may set other conditions on a project/site specific basis.

7.6 Orders of Conditions for Violation Permits

Orders of Conditions for permits associated with violations shall include explicit dates for milestones and completion of work.

7.7 River Front Area Protection

For the purposes of this Bylaw the protections afforded to River Front Areas under the 1996 amendment to the Massachusetts Wetlands Protection Act shall follow the regulations as listed under sections 7.1 and 7.2 for adjacent upland resources except that the reach of jurisdiction shall extend 200 feet from the stream or river bank as specified by state law.

7.8 Storm Water Runoff Best Management Practices

All storm water runoff systems shall at minimum conform to best management practices as specified in the Sudbury Planning Board’s Storm Water Runoff Regulations. The Conservation Commission may impose more stringent conditions where resource values and functions warrant it.

7.9 Alternative Analysis

The Sudbury Wetlands Administration Bylaw clearly states that projects and associated disturbances should be located outside of any resource that falls under the jurisdiction of this Bylaw, including the adjacent upland resource area. Practical alternatives to locate the project outside these areas must be investigated and should one or more prove feasible the plan must be amended to relocate all activities accordingly.

The Commission shall consider as practical alternatives options that were available to the applicant but appear to be precluded due self-imposed hardships and constraints (e.g., lot, roadway, and drainage layouts engineered without prior regard to impact on Bylaw resources.)

If in the Commission’s view there are no practical alternatives project impacts must be minimized and mitigated so there are no adverse impacts to the resources. If the Commission determines that the project will have significant adverse impacts on the resources then the project shall be denied.



9.1 Appurtenance

The term appurtenance shall mean any structural adjunct to a single family residential structure, such as a septic system, garage, deck, porch, patio, driveway, or sidewalk. Items not considered to be appurtenances include, without limitation, swimming pools, tennis courts, lawns, landscaping or gardens, and in-ground sprinkler systems.

9.2 Direct discharge

Direct discharge includes, without limitation, any outfall of water that empties into the resource area or adjacent upland resource, including infiltration.

9.3 Distance:

All distances noted in the Bylaw (excluding depth), such as adjacent upland resources distances, are planar distances measured along a single elevation. Consequently, on steeply sloped topography the measured over-ground distance may not accurately reflect the distances specified in the permits and conditions specified by the Bylaw. In particular, the 100-foot adjacent upland resource on steeply sloped land will measure considerably more than 100 feet when measured over-ground on site.

9.4 Existing:

The term "existing" as used in the Bylaw shall mean existing in full as of July 27, 1994, unless specified otherwise in the Bylaw.

"Existing house foundation" refers to the foundation of single family house where the house was fully constructed prior to July 27, 1994.

9.5 Discharges into Wetlands

Discharges into wetlands, as listed under Section 2, shall include, without limitation, any discharge from the project that flows to a wetland resource or adjacent upland resource through new or existing drainage structures, including existing road drainage pipes, that empty into wetland resources or adjacent upland resources regardless of the distance between the project site and the wetlands resources or adjacent upland resources.

9.6 Hydraulic Connection

A hydraulic connection is any surface water connection, whether natural or artificially created or modified, including but not limited to: surface and subsurface pipes, culverts, ditches, etc.

9.7 Recreation

The term recreation connotes passive recreation activities that do not conflict with or diminish other wetland values and functions. Examples include, without limitation, bird watching and other nature studies, walking and hiking, canoeing, and as appropriate fishing, hunting, etc.

9.8 Wet Detention Basin

A wet detention basin is a detention basin designed to hold water for at least two continuous months during the spring/summer, where the ponding area covers at least one-third of the basin floor to an average depth of six inches of water, which supports wetland vegetation, and which meets the other design requirements set by the Conservation Commission.

For the purposes of the Bylaw a wet detention basin shall be considered a constructed wetland and not acceptable as part of a wetland replication plan. As a constructed wetland a wet detention basin shall be presumed to serve two wetlands values: pollution attenuation and flood control. The adjacent upland resource for wet detention basins shall extend two feet beyond the break in slope of the detention basin, unless the basin wetland attains dimensions consistent with jurisdiction under the Massachusetts Wetlands Protection Act in which case a full 100 foot adjacent upland resource shall apply.

9.9 Volume Of A Detention/Retention Basin

Basin volume shall be calculated as that volume contained between the basin’s 100-year flood elevation and the lowest elevation of the basin floor, except that in the case of a wet detention basin 50% of the calculated volume shall be used for fee determination purposes.

9.10 Intermittent Stream

Intermittent stream is a defined channel with a hydraulic gradient through which water flows during part of the year and which either flows out of, into, or within a wetland resource under this bylaw. A portion may flow through a culvert or under a bridge.  [see section 2.3 for defining characteristics]

9.11 Vernal Pool Species

Any species of reptile or amphibian, that breeds in a vernal pool, whether obligate or facultative.  Any obligate invertebrate species.

9.12 Flood Storage as an Alteration

The term "alter" includes storage of flood waters and storm water runoff waters in wetlands. Storage of flood waters and storm water runoff is prohibited unless the Conservation Commission deems that such action would enhance wetland values and functions.

10.     SECURITY

10.1 Orders Of Conditions & Bonding

In the specifying of an Order of Conditions and setting of bond the Conservation Commission may, at its choosing, take into account the prior history of applicant and the applicant's representatives, consultants, builders, or other contractees. When in the Commission's opinion prior instances of disregard for orders of conditions, violations of wetlands regulations and policies, practices known to threaten wetlands values and functions, or other failures to fulfill legal obligations pursuant to wetlands protection raise questions about the applicant's willingness or ability to abide by permit requirements the Commission can set additional conditions and impose bond requirements to ensure adherence to permit requirements.

10.2 Permitting in the Context of Outstanding Violations

No permit shall be issued for any project to an applicant who has an outstanding violation of this Bylaw for which either (a) no corrective Order of Conditions has been recorded at the Registry of Deeds, or (b) which is not under legal appeal.


11.1 Recording a Notice of Violation

The Conservation Commission shall record a Notice of Violation issued under Section 11 of this Bylaw with the Registry of Deeds when (1) it has information that the property in violation of this Bylaw may change ownership, (2) when the owner of the property in violation has failed to respond to the Notice of Violation after ten business days, or (3) when the owner of the property in violation has failed to file a corrective Notice of Intent within 30 days of receipt of the Notice of Violation. 

11.2 Municipal Lien Certificate

The Conservation Commission may request that the Town Treasurer record a municipal lien certificate against any property for which outstanding fines levied under this Bylaw have not been paid.

11.3 Abatement of Fines

The Conservation Commission may abate fines imposed under this Bylaw, in part or in whole.