Land Subject to Coastal Storm Flowage (LSCSF) is the only resource area that lacks performance standards. As a result, the WPA provides Conservation Commissions very limited ability to condition projects to protect against coastal flooding and storm damage. MA DEP has been considering adding performance standards for LSCSF for many years; recently they indicated they will finally release proposed standards in the summer of 2021. Duxbury, Hingham, Marshfield, and Scituate all have performance standards (LSCSF). Most of the towns have had this language in place for a number of years, including language that references sea level rise.

Each of the communities below has excellent introductory language explaining the importance of regulating LSCSF and the associated wetland values.

• In Duxbury, projects cannot have adverse or cumulative adverse effects on the wetland values of LSCSF. Activities in A-zone must incorporate a predicted sea level rise of 2.8 feet per 100 years in project design and construction. In V-zones and AO-zones new construction and new structures; new or expanded coastal engineering structure unless of loose, slope-stone design; and new or expanded septic are prohibited. In V-zones additions to existing structures and new paving for roads, driveways, and parking lots are also prohibited. Duxbury also requires a permit for installation of impervious surfaces in V and AO-zones. Total impervious surfaces cannot exceed 500 square feet; walkways are limited to 36 inches in width.
• Marshfield has similar language but does not address coastal engineering structures.
• Hingham requires projects in VE and A-zones to, at a minimum, incorporate 1 foot of projected sea level rise into project design and construction. In V-zones, new construction, and new structures; impermeable paving for roads, driveways, and parking lots; new or expanded coastal engineering structure unless of loose, slope-stone design; and new or expanded septic are prohibited. New construction and new structures on vacant lots; new or expanded coastal engineering structure unless of loose, slope-stone design; and new or expanded septic are also prohibited in A-zones.
• Scituate requires projects in VE and A-zones to, at a minimum, incorporate 1 foot of projected sea level rise, and land migration due to sea level rise, into project design and construction. Foundations other than open pilings, new or expanded roads, driveways, or parking lots, or paving of existing roads, driveways, and parking lots; and new or expanded coastal engineering structures are prohibited in VE-zones.

Expanding jurisdiction is not a guarantee of greater climate resilience, but it provides the opportunity to consider impacts and provide protection to areas that may be subject to climate impacts in the future. Communities have taken a variety of approaches to expanding jurisdiction. Most expand buffer zones. But examples also include treating buffer zones as resource areas and regulating the .2% chance (500-year) flood zone.

• Some communities treat or define buffer zone areas as regulated resource areas. Medway (2.18) deems the 100-foot buffer area to be a resource area. Sharon (2.29) treats the first 50-feet of the buffer zone as a regulated area. Bolton extends the resource area into the first 25-feet of buffer zones. Southborough treats the first 20-feet of the buffer zone as resource area.
• Wellesley treats the buffer zone as a resource area with established performance standards.
• Brookline, Dover, Watertown, and Woburn have a 150-foot buffer zones. The Brookline buffer does not apply to vernal pools. Watertown does not have a buffer zone for Land Under Water, or Land Subject to Flooding. Woburn does not have a buffer zone for Land Subject to Flooding. Framingham has a 125-foot buffer zone; it does not include Land Subject to Flooding.
• The following communities have adopted a 100-foot buffer to Land Subject to Flooding: Bedford, Bellingham (247), Burlington, Dedham, Hamilton (XVII), Lincoln, Medfield, Milford, Millis, Norfolk, North Reading, Norwood, Peabody, Sherborn, Southborough, Stoughton, Stow, Sudbury, Wenham, and Wrentham.
• Millis extends the definition of Land Subject to Flooding to the .2% (or 500-year) FEMA flood zone.
• The following communities have adopted a 100-foot buffer to Lands Subject to Coastal Storm Flowage and to Lands Subject to Flooding: Lynn, Marblehead, Milton, Pembroke, Quincy, Revere, Saugus, and Weymouth.
• Danvers and Wrentham have 100-foot buffer zones to Isolated Land Subject to Flooding (ILSF). Norwood and Maynard have a 25-foot buffer to ILSF. Sudbury has a 25-foot upland resource area adjacent to ILSF.

As average rainfall rates increase and larger storms become more frequent, we can expect stormwater flooding to become an even greater challenge. Massachusetts regulates stormwater under the Wetlands Protection Act. The regulations are designed to address water quality. Yet the permit requirements can reduce flooding in addition to pollution by requiring greater infiltration of stormwater at the project site.

Many communities have applied stricter stormwater requirements than those provided in the Wetlands Protection Act. Strategies include updating rainfall rates, expanding the application of the stormwater standards, and applying additional standards.

Current state stormwater regulations rely on rainfall data from 1961 to size stormwater infrastructure even though rainfall has increased considerably. MA DEP is currently considering updating rainfall rates. Many communities have already updated their requirements for rainfall records using data from the Northeast Regional Climate Center (Cornell) or from NOAA Atlas 14.

• The following communities require the use of Cornell rainfall records for sizing stormwater infrastructure: Arlington, Bellingham (247), Danvers, Hopkinton, Ipswich, Lynn, Norwood, Walpole, Wayland, and Wenham.
• The following communities require the use of NOAA Atlas 14 rainfall records for sizing stormwater infrastructure: Braintree, Wellesley, and Woburn.

Wetlands Protection Act stormwater regulations do not apply to single-family homes and have limited applicability to residential housing of up to 9 units. Some municipalities have extended the regulations beyond the state WPA applicability.

• Norwood applies the state stormwater regulations to projects that increase impervious area or result in increased stormwater runoff.
• Manchester applies the state stormwater regulations to all projects with limited exceptions.
• Littleton applies the state stormwater regulations to all industrial, commercial, institutional, office and transportation projects; all residential projects of more than one unit; all development and redevelopment that disturbs one or more acres of land; and increases of impervious area of 1,000 sq/ft or 5% whichever is less.
• Ipswich applies the state stormwater regulations to projects that disturb 10,000 sq/ft or 50% of a parcel, whichever is less.
• Dedham incorporates the town stormwater regulations which apply to projects that disturb 500 sq/ft and require infiltration of 2” x the impervious area.
• Canton applicants must comply with the town stormwater bylaw in addition to the state WPA standards. The stormwater bylaw applies to disturbances of more than 5,000 sq/ft.
• Wellesley requires all industrial, commercial, institutional, office, residential, and transportation projects comply with the state stormwater regulations.

The state wetlands regulations require that the post-development peak discharge rate be equal to, or less than, the pre-development rate for the 2-year and the 10-year 24-hour storms.

• Wellesley requires that the post-development peak discharge rate be at least 5% less than the pre-development rate for the 2-year and the 10-year 24-hour storms.

The state wetlands regulations define Isolated Land Subject to Flooding (ILSF) as “an isolated depression or closed basin without an inlet or an outlet. It is an area which at least once a year confines standing water to a volume of at least ¼ acre-feet and to an average depth of at least six inches”. These areas are important for flood control and stormwater storage. Many communities have reduced the area and/or flood volume required to meet the definition for ILSF.

• Cohasset and Weymouth do not have a minimum size threshold for ILSF. Bellingham (247) does not have a size threshold and requires that ILSF confine water once a year.
• The following communities use a reduced acre-foot standard, and/or reduced depth: Dover – 1/6 acre-foot, 6 inches. Norwell and Sudbury– 1/8 acre-foot, 6 inches. Bedford 1/8 acre-foot or 10,000 sq/ft, whichever is smaller. Sherborn – ¼ acre foot, 4 inches.
• The following communities set their standard based on cubic feet. Gloucester (12) – 1,000 cubic feet, 6 inches, Lynn – 2,000 cubic feet, 6 inches, Wrentham – 3,000 cubic feet, Saugus – 5,000 cubic feet. (¼ acre foot = 10,890 cubic feet)
• The following communities have established a standard based on square feet. Franklin – 500 sq/ft (standing water for 2 weeks). Bolton – 1,000 sq/ft, 6 inches. Needham and North Reading – 2,000 sq/ft, 6 inches. Brookline – 2,500 sq/ft. Wellesley – 2,500 sq/ft, Ashland: 5,000 sq/ft, 6 inches.

The WPA requires compensatory storage in Bordering Land Subject to Flooding if Commissions judge that loss of storage will increase flooding during peak flows. A few communities require additional compensatory storage beyond a 1:1 ratio. Bellingham also requires compensatory storage for Isolated Land Subject to Flooding.

• Arlington, Bellingham (247), and Dedham require a 2:1 ratio for compensatory storage. Stow requires 110% replacement storage. Marblehead gives the Commission authority to require additional compensatory storage.
• Bellingham (247) also requires a 2:1 ratio for compensatory storage for Isolated Land Subject to Flooding.

See also: Water Conservation Regulations

Despite projections for increased rainfall and flooding, climate projections for Massachusetts also indicate an increased probability of drought. This reflects analysis that indicates a likelihood of more rain in the winter and spring and slightly decreased rain in summer and fall. The decrease in rain, combined with earlier snow melt, and higher temperatures that will increase evaporation and reduce soil moisture, account for the drought projections.

• Medway (2.18) reserves the right to limit the size of lawns and impose irrigation restrictions in order to protect groundwater supplies.
• Sharon (2.29) reserves the right to limit the size of lawns and impose irrigation restrictions in order to protect and preserve the hydrology of wetlands and water.

See also: Tree Regulations page

Trees can play an important role in mitigating heat and flooding. According to the EPA, suburban areas with mature trees are 4-6 degrees cooler than new suburbs without trees, and shaded surfaces can be 25-40 degrees cooler than the peak temperatures of unshaded surfaces. Trees also absorb remarkable quantities of precipitation. A report by the Center for Urban Forest Research found that New York City streets trees intercept an average of 1,432 gallon of stormwater per year, reducing stormwater runoff by nearly 900 million gallons annually.

• Braintree regulations recognize the importance of trees for climate mitigation. Tree replacement is required at a 1:1 ratio in the 50-100 foot buffer; a 2:1 ratio in the 0-50 foot buffer; and a 3:1 ratio in a resource area. Where space is not available for re-planting, the applicant must contribute $250 per tree not replaced to the Commission’s Tree Planting Fund.
• Dedham requires that all healthy trees removed be replaced at a minimum 2:1 ratio. The Dedham guidelines for tree removal recognize the stormwater absorption and cooling functions of trees in addition to their wetlands functions and values.
• Norwood has a No Build Area that is the first 25 feet of the buffer zone. From 25 to 100 feet from the edge of resource areas is a Tree Filter Zone. In the Tree Filter Zone, no more than 50% of trees (6” diameter at 3 feet) can be removed.
• Dover requires that no more than 50% of tree cover be removed from any 100-foot section of Buffer Zone, except hardship cases where no reasonable alternative exist. Tree cover is defined as trees with 4” diameter at 4 feet. For subdivisions and 5-acre parcels 80% of tree cover in the Buffer Zone must be preserved except where no reasonable alternative exists.
• Wenham Tree Removal Policy allows tree removal in resource areas and their buffers only if it is a hazard, substantially interferes with landowners use of the property, is invasive, is less than 4” at four feet above the ground. Trees greater than 4” at four feet above the ground must be replaced.
• Wakefield Tree Removal Policy applies to resource areas and their buffers. Removal is allowed only for safety threats or if a tree substantially interferes with landowners use of the property. Applies to trees 6” at four feet above the ground or greater. Trees must be replaced per linear foot.