INDEX
Suitability Study for a Proposed Affordable Housing Development in Southampton, MA Client: Southampton Housing Authority Designer: Gallagher Hannan Conway School of Landscape Design Fall 2013
1. Context and Background Information 2. Existing Conditions 3. Slopes & Drainage 4. Soils & Erosion 5. Drainage, Vegetation & Active Solar 6. Summary Analysis, Bridges & Culverts 7. Road Options 8. Alternative Development Strategies 9. Alternative #1 10. Alternative #2 11. Alternative #3 12. Plant Palettes 13. Managing Stormwater & Streambank Restoration 14. Questions That Remain & Next Steps Appendixes A&B
In 2001, the town adopted the Community Preservation Act (CPA), which is a Massachusetts law enabling communities to raise funds for historic preservation, open space, and affordable housing. The funds come from an increase in property taxes. Because of the CPA, the Town of Southampton has almost $200,000 in funds set to be used for affordable housing. In 2010, the Town funded The Southampton Housing Needs and Action Plan, an objective of which was to figure out how to more effectively use CPA funds to increase the town’s affordable housing. The assessment found that there was a diversity of types of households in Southampton, many of which would qualify as affordable housing. It also concluded that Southampton is a desirable place to live, but quickly is becoming unaffordable.
Laurie Drive & the Potential Affordable Housing Building Site The Laurie Drive cul-de-sac and its ten houses, were built in 1964. According to one resident, Bruce Betsold, the developer was hoping to develop on the plot at the end of the cul-de-sac but was unable to due to inaccessibility because of steep slopes and an intermittent stream. As a result, the resident says, the developer went out of business and the town of Southampton acquired the six acres of woodland. Now, town officials are asking, since the Town already owns the land, is this a suitable place to build affordable housing? Meanwhile, neighbors are worried that the subsidized development will bring down the value of their homes and also greatly increase traffic on their quiet dead-end street.
Southampton
About Southampton
Southampton is a twenty-minute commute to Springfield or Holyoke, two large Western Massachusetts urban centers, and about a fifteen-minute drive to Interstate 91, a major Massachusetts highway. Most of the residents commute out of Southampton for work, although there is still a strong farming community. The inhabitants of the town value its rural nature, and therefore the town would like to ensure that this new development is in keeping with this rural, suburban aesthetic. There is no public transportation in the town, so any resident of the new development would have to have access to a car.
Percentage of affordable houses in Massachusetts towns as of Winter 2011. The Town is worried that residents might move out of Southampton and into one of the surrounding towns, where more affordable housing is available.
Determine if it’s possible to build a driveway into the site and where it might go. Determine how many houses could fit on the site, their locations and: • Give preference to possible elderly housing. • Determine if there’s enough room for septic systems. • Explore the possibility of passive and/or active solar energy.
Not for construction. Part of a student project and not based on a legal survey.
The Laurie Drive cul-de-sac, with the potential site for affordable housing outlined in yellow.
Gallagher Hannan
Laurie Drive, Southampton, MA Client: Town of Southampton
Currently Southampton has 44 units of affordable housing and, under the Comprehensive Permit Act, they need 200 units. The Comprehensive Permit Act, or Chapter 40B, is a Massachusetts law that attempts to encourage development of affordable housing by allowing developers to override aspects of municipal zoning bylaws and other requirements. A town is only exempt from this law if it has more than 10% of its housing defined as affordable under 40B. The Southampton Housing Authority is worried that a developer could build affordable housing that wouldn’t be in keeping with the nature of the town’s character, and are also worried that they are pricing out some of the town’s residents, specifically young families and elderly retirees. The Housing Authority is specifically interested in finding a place to build affordable housing for the elderly, because such a project is more likely to have the support of the citizens of Southampton.
Determine the suitability of the site for an affordable housing development.
Suitability Study for Proposed Affordable Housing Development
Project Goals
The State of Massachusetts considers a unit affordable if it is part of a “subsidized” development built by a public agency, non-profit, or limited dividend corporation. In an affordable housing development, at least 25% of the units must be income restricted to households with incomes at or below 80% of the area’s median income, and rent or sales prices must be restricted to affordable levels. In Southampton, 80% of the median income for a family of four is $64,400, for a single resident it is $45,100.
Context & Background Information
The town of Southampton has been looking for suitable plots of land on which to build affordable housing, and to do so, enlisted the help of the Pioneer Valley Habitat for Humanity, which has resources to evaluate building sites. In the last several years, the Housing Authority and Habitat have assessed all town-owned plots of land, but none have been deemed suitable for building. The 6-acre plot at the end of Laurie Drive is the last piece of Town-owned land the Housing Authority is assessing.
The Conway School Graduate Program in Sustainable Landscape Design and Planning Fall 2013
Affordable Housing in Southampton, MA
1/22
Neighbors’ houses
Not for construction. Part of a student project and not based on a legal survey.
Indicates area of approximated topography lines
The topography lines on this map are created from a combination of a survey done by Conway School students and a map downloaded from the Massachusetts GIS website. The survey is shown with two-foot contours (in the northwest section of the site) and the Mass GIS map is shown in ten-foot contours. The topography lines on the map are therefore very much an approximation especially in the northeast corner of the site (the shaded area), where the Mass GIS topography lines were moved to accommodate the survey data. BEFORE ANY MORE WORK IS DONE, A PROFESSIONAL SURVEY IS RECOMMENDED.
Laurie Drive, Southampton, MA Client: Town of Southampton
Neighbor’s house
Existing Conditions
Neighbor’s house
Suitability Study for Proposed Affordable Housing Development
Gallagher Hannan
The Conway School Graduate Program in Sustainable Landscape Design and Planning Fall 2013
Intermittent stream
2/22
• •
•
Criteria •
Dairy farm pastures slope down to the east
•
A driveway should be <10% when paved and <8% when unpaved, to make it drivable during snowy icy winters. It is best to build houses on <10% grade to reduce grading and, therefore, cost.
30% slopes on the Eastern side of the intermittent stream
To the North: There are >30% slopes on privately owned woodland and a distance of over a 1/3 of a mile to Whiteloaf Road.
To the West: The
Wate r
Line
Road
Holy oke
Middl e
Town is hoping to build a shared driveway into the site from the end of the cul-de-sac.
oad loaf R White
>30% 20-30% 10-20% <10%
This band of woodland slopes very steeply to the northwest.
Valle y
Road st To the South: All the lots to the south between the property and Valley Road are privately owned. Below the site is the Holyoke waterline, which runs from the reservoir in Southampton down into Holyoke. It is owned and maintained by the town of Holyoke.
m rea
To the East:
There are dairy farm pastures for about a 1/4 mile down to Middle Road. The east side of the property has the gentlest slopes between the site and the road.
Not for construction. Part of a student project and not based on a legal survey.
•
Very steep slopes (>20% and often >30%) snake along the western and southern sides of the site, and up the southeastern edge. An intermittent stream flows down the western side of the site at the bottom of the steep slopes. Two areas of <10% slopes exist on the site: a 1/2 acre area in the middle of the site and a 1/3 of an acre on the northern boundary of the site. An old logging road historically provided access into the site from the south. A house now cuts off this old road from Valley Road.
Laurie Drive, Southampton, MA Client: Town of Southampton
•
•
Avoid siting a driveway on western and southern slopes of this site, as slopes this steep are very erodible. Explore alternative access points. The less steep slopes on the southern and eastern sides of this site would provide easier access (as historically they have, as demonstrated by the old logging road). Take advantage of the two flattest areas on the site (<10%). These are the best places to build houses without having to do significant grading.
The Conway School Graduate Program in Sustainable Landscape Design and Planning Fall 2013
Observations
•
Gallagher Hannan
Design Direction
Suitability Study for Proposed Affordable Housing Development
Slopes
Slopes & Drainage
VERY steep slopes make siting a driveway difficult, and alternate access points should be evaluated. Areas with <10% slope will prove to be the best sites for low disturbance, low cost building.
3/22
*For more pictures of the stream during this July storm see Appendix A.
• • • •
Soils are sandy, ranging from sandy loam to medium sand (Holyoke Fine Sandy Loam) and will likely be very suitable for septic systems. Soils are very deep layers of sand, in places 10 feet above bedrock. Soils percolate very well at <2 min/inch. (See appendix B for complete Heritage Survey Inc. Perc Test). Sandy soils erode easily once disturbed, as is demonstrated on the already very eroded eastern bank of the intermittent stream. Exposed bedrock is Jurassic Red Sandstone, which is also known to be very erosive. Soils are currently protected on the majority of the site by a healthy, established forest. Deep observation holes dug as part of the Heritage Survey test show infill from previous construction (sand on top of loam), which appears to be constricting the stream channel and forcing the stream to undercut the far bank.
Design Direction • • • • • •
Plan with caution as these soils erode easily when disturbed, and are difficult to use for shaping landforms or planted retaining work. Take advantage of the high permeability of soils, by designing for water catchment basins that allow runoff to percolate back into the ground, replenishing the water table. Create as many low-volume, infiltration areas as possible, to avoid point source drainage and high volumes of running water down steep fragile slopes Avoid driveway and housing layouts on steep fragile slopes, and design ideas which rely on major site disruption in steep areas. Propose native plantings suitable to these soils and growing conditions. Propose a stream-front restoration plan, to prevent further erosion of the stream bank.
Laurie Drive, Southampton, MA Client: Town of Southampton
• •
•
On-site stream with highly eroded banks (after).
Soils & Erosion
Observations
On-site stream with gushing water through sandy banks (photo taken by Bruce Betsold, a resident of Laurie Drive, during a storm on June 29, 2013). Climate change most likely means that we will see more extreme storm events such as this one in the future.
Suitability Study for Proposed Affordable Housing Development
Soils & Bedrock
Examples of serious erosion along the eastern bank of the intermittent stream. This erosion is most likely the result of an unnaturally narrow stream corridor created when construction fill was dumped next to Laurie Drive after initial construction, forcing the stream to undercut the site’s highly erosive sandy soils. If these conditions are not changed, the stream will almost certainly continue to undercut and erode its eastern bank.
Not for construction. Part of a student project and not based on a legal survey.
The Conway School Graduate Program in Sustainable Landscape Design and Planning Fall 2013
Deep sandy soils should be treated with EXTREME caution when present on such steep slopes to prevent more large scale erosion.
Gallagher Hannan
Areas of serious erosion
4/22
Observations
A storm drain at the end of Laurie Drive pipes water directly into the stream
Entire site drains into intermittent stream. Overloaded stream capacity already creating significant erosion.
Indicates the direction water is moving
Vegetation
Active Solar Energy
Using solar panels on this site will be difficult because so many trees will need to be removed. However, selective cutting can be done to increase southern access and bring more light and heat into the site (passive solar).
Observations The stream drains into a wetland approximately 1 mile south of the site.
• •
Mature white pine forest dominates site and stabilizes slopes with significant root system. Wetland indicator species suggest wetland areas along stream. Invasive exotics found throughout the site, especially along the pasture-land to the east, and near the Holyoke Water Line.
Drainage, Vegetation & Active Solar
•
*For a complete list of plants observed on site see Appendix A
Design Direction • • • • •
Delineate all areas of disruption, including trees to be removed to increase solar access. Delineate wetlands, to determine relevant setbacks. Identify invasive species and create a management plan. Take advantage of native woodland species adapted to these soils and site conditions. Provide mitigation designs for removal of stabilizing tree root systems, including quick planting strategies on all disturbed soil and bio-engineering on proposed slopes.
Laurie Drive, Southampton, MA Client: Town of Southampton
•
Plan with caution. Driveway on western slope will increase non-point source pollution going in stream and unmanaged runoff from the addition of impermeable surfaces on the site will overload stream further and increase erosion. Manage stormwater, with swales and infiltration basins to retain and filter run-off, to avoid channeling excess water, which could potentially greatly increase already very problematic erosion.
Suitability Study for Proposed Affordable Housing Development
Design Direction •
The orange area indicates the area in which 70’ trees block solar photovoltaic panels on a house’s roof (shown in brown).
Not for construction. Part of a student project and not based on a legal survey.
Drainage • •
The Conway School Graduate Program in Sustainable Landscape Design and Planning Fall 2013
Gallagher Hannan
Steep slopes, with the addition of impermeable surfaces, draining towards an intermittent stream necessitate a strong stormwater management plan. Mature forest requires selective cutting to bring light into houses.
5/22
There is a 100’ buffer from the intermittent stream within which permission from the Conservation Commission is necessary in order to build.
• •
Cons: • •
Erosion Drainage direction Road Early successional herbaceous plants Setback from stream >30% 20-30% 10-20% <10%
Requires less maintenance than a bridge. Cheaper if higher off stream bed (dirt fill over a culvert is cheaper than concrete pile-ons for a bridge); however, either way building a road so high above the stream bed would be costly. Impacts the stream bed. Could cause erosion (if the opening isn’t wide enough during a storm event, water could dam up)
Bridge: Pros: • • •
Reduces ecological impact on the stream bed Automatically passes MA Stream and River Crossing Standards. Allows for maximum lateral movement by the stream to reduce the possibility of erosion.
Cons: • •
More expensive if higher off the stream-bed. Most likely will require more maintenance.
The Conway School Graduate Program in Sustainable Landscape Design and Planning Fall 2013
Pros:
Gallagher Hannan
Culvert
Not for construction. Part of a student project and not based on a legal survey.
Property boundary
The Town is proposing that all zoning restrictions are waived on this site, including setbacks, and number and proximity of units.
Laurie Drive, Southampton, MA Client: Town of Southampton
Intermittent stream
Analyzing Bridges and Culverts
Suitability Study for Proposed Affordable Housing Development
Views into pastures
Zoning Restrictions
Summary Analysis Bridges & Culverts
Conditions on the site make building a road up the western slope inadvisable. There are flat areas for building, although run-off will have to be carefully managed.
*pictures and information from Dave Vreeland of Vreeland Design Associates
6/22
515 feet long (as shown here) <10% slope
> 1/4 mile long 5% slope (according to Mass GIS map)
PROS:
•
CONS:
• A section taken from the middle of the driveway shows that a huge amount of grading would be necessary to build this driveway, which is VERY inadvisable on such steep erosive soils. .
CONS: • • •
A LOT of disturbance to a HIGHLY erodible slope that will probably continue to get undercut by the intermittent stream. Maintaining the bridge could be expensive. Traffic would increase on Laurie Drive, upsetting residents.
Avoids the very steep slopes and the highly eroded/ undercut areas on the eastern bank of the stream (seen above in orange) Allows water to infiltrate back into the soils before reaching the stream, filtering out non-point-source pollution and decreasing the likelihood that drainage from the road will increase the stream’s flow.
CONS: • • • •
Crosses a protected floodplain necessitating a long bridge (40’ +). Traverses steep slopes (expensive, a lot of cut and fill etc.) Maintaining the bridge could be expensive. Traffic would increase on Laurie Drive, upsetting residents.
PROS: • • • •
Avoids the stream. Avoids steep slopes. Traffic is not increased on Laurie Drive. Enters the site on the northeastern side (ideal for siting houses because the driveway is occupying the least desirable, coldest part of the site). The farmer might find a town maintained road into his property desirable.
• • •
Avoids the stream. Avoids steep slopes. Traffic is not increased on Laurie Drive.
•
Right-of-way permission required from the neighbor. • Could be necessary to blast through bedrock, because the wooded band between Valley Road and the CONS (Issues): site is very steeply sloping to the west. Necessary to cross the water line (still unclear wheth- • Necessary to get right-of-way permission from the farmer (or buy the land). er or not the town of Holyoke would permit this)
• •
Criteria: • •
Must be at least 18’ wide (for two-way traffic) Can be no more than an 8% grade, if unpaved (this is always recommended because of snowy, icy conditions in the winter.)
Road Options
PROS:
Additional Information: •
Usually a shared driveway would be maintained by the tenants, but to make the housing more affordable, the Town is considering maintaining the driveway.
Not for construction. Part of a student project and not based on a legal survey.
515 feet long (as shown here) 8% slope
Suitability Study for Proposed Affordable Housing Development
550 ft long (as shown here) 8% slope
Driveway #3: Through the Field RECOMMENDED
Recommended with Reservations
Possible, with Reservations
Laurie Drive, Southampton, MA Client: Town of Southampton
Driveway #3: Off Valley Rd.
Driveway #2: Around the South-side
The Conway School Graduate Program in Sustainable Landscape Design and Planning Fall 2013
Driveway #1: Up the Slope NOT RECOMMENDED
Gallagher Hannan
Building a driveway to the top of the site from Laurie Drive will be expensive and require careful engineering. At this time, the best alternative seems to be to build a road through the pastures to the east.
7/22
TRADITIONAL SUBURBAN DEVELOPMENT • • •
Involves a lot of disturbance for only a handful of houses. Centers around cars. Doesn’t foster community.
Cluster developments are especially great for kids, who can wander and play freely.
POCKET NEIGHBORHOODS CAN BE A GREAT ALTERNATIVE FOR SENIOR CITIZENS. As the first wave of baby boomers reaches retirement, many such communities (sometimes called “saging communities”) are popping up. They often have community buildings to encourage interaction and to offer a space for residents to cook meals together and pursue hobbies and activities with like-minded individuals with similar needs. Below is shown Silver Sage, a senior-only cohousing development in Boulder, CO.
CLUSTER HOUSING • • • • •
Maximizes space on the site, allowing for many more houses. Fosters community, because the houses are arranged to encourage neighborly interaction. Encourages outdoor living, with a shared common green space in the center of the houses. Keeps cars at bay, and is designed to be human scale, and walkable. Allows the town to grow while still maintaining open space and farmland elsewhere.
Although it is not always possible to have parking right next to residents’ houses, as is the case in the cluster housing development above, many residents say that they enjoy walking from their cars as it gives them a chance to happen upon, and visit with, neighbors.
The Conway School Graduate Program in Sustainable Landscape Design and Planning Fall 2013
8/22 *images from www.pocket-neighborhoods.net
Not for construction. Part of a student project and not based on a legal survey.
ATTACHED UNITS can save even more space, are often cheaper to build, and are not just for urban sites. Shown below is the Cheesecake Consortium, a co-housing community in a redwood forest
Gallagher Hannan
HOUSES DESIGNED FOR CLUSTERING are tall and narrow, with public rooms on one side and private on the other, to give residents a sense of separation even in tight quarters (houses below designed by Kraus-Fitch Architects in Amherst).
Laurie Drive, Southampton, MA Client: Town of Southampton
Cluster developments encourage neighborly interaction and foster community.
Taking it one step further...
Suitability Study for Proposed Affordable Housing Development
Some examples of existing cluster developments (also known as “pocket neighborhoods”)
Alternative Development Strategies
This site has a limited amount of flat, buildable area, and access will most likely be expensive, so it is recommended that the Town look at development alternatives that maximize usable space.
A A market rate lot in the northern part of the site can be reached by a going straight down the shared driveway. Turning left leads to... B a parking court (16 cars) for small cluster development, with a fire-truck turn-around.
A
C Open commons and a shared garden space is fire-truck accessible. Houses on the stream side are
single story with full basement. Houses on the pasture side are two stories, built into the hillside, acting as a retaining wall. Around the houses, mown turf and low plantings makes up the majority of the open space, with native shrubs placed as privacy screens.
E Stormwater management requires careful planning. A network of swales and infiltration basins to
retain and filter water from impermeable surfaces are necessary to avoid channeling the water, which could potentially greatly increase the already very problematic erosion on the site.
F A 60-foot by 60-foot shared septic system. For more information about determining septic system
E
A
size see Appendix B.
A’
B
B’
B
Laurie Drive, Southampton, MA Client: Town of Southampton
LAURIE DRIVE
Suitability Study for Proposed Affordable Housing Development
D A native meadow leads to a meandering woodland trail. At the edge of the woods shrubs and small trees create habitat, biodiversity and a buffer for the forest interior, which is planted with edibles and woody plants with bright fall foliage. At the end of the trail, benches look over sloping dairy pastures.
A-A’
Infiltration basin
See cover for conceptual drawing E
HO
F
LYO K
EW ATE R
LIN
E
D
Parking lot (3% grade)
50% vegetated slope
C
B-B’
One story house
Path
Path
Commons
Two story house
*Red lines indicate current topography.
Alternative #1
B C
Not for construction. Part of a student project and not based on a legal survey.
9 units total, 8 affordable housing units
The Conway School Graduate Program in Sustainable Landscape Design and Planning Fall 2013
E
Gallagher Hannan
Housing Alternative #1: Sale of market rate lot helps fund a small cluster development of single-family homes.
9/22
B
A six-unit cluster development on the flattest portion of the site minimizes grading (duplexes could be built here as well). Open commons and a shared garden space is fire-truck accessible. Houses on the stream side are single story with full basement. Houses on the pasture side are two stories, built into the hillside, acting as retaining walls. Around the houses, low vegetation and mown turf make up the majority of the open space, with native shrubs and grasses placed as privacy screens.
Aâ&#x20AC;&#x2122;
C A trail connects the two developments, meandering through a native meadow and skirting the
LAURIE DRIVE
wooded ridge. After crossing the road it continues up through a buffer of shrubs and small trees which create habitat and biodiversity, and into the forest interior, which is planted with edibles and woody plants with bright fall foliage. At the end of the trail, benches look over rolling farm fields.
C
D A network of swales and infiltration basins retain and filter water from impermeable surfaces (parking lots, roads, roofs).
E
A 65-foot by 65-foot shared septic system. For more information about determining septic system size see Appendix B.
B
HO
E
LYO K
EW ATE R
LIN
E
D
graded commons
two-story duplex
10 ft of 2% grade to move water away from the houses
Alternative #2
A-Aâ&#x20AC;&#x2122;
porch and two-story duplex
Not for construction. Part of a student project and not based on a legal survey.
Two duplexes make best use of space while increasing the number of units on the site (attached housing may also be eligible for funding not available to single family units according to Rita Farrell of the MA Housing partnership). Parking (8 cars) is along the road. A <5% path (wide enough for a cart and reinforced for occasional vehicular traffic) leads down between the houses and then wraps back up to meet the road to allow for through fire-truck access.
Laurie Drive, Southampton, MA Client: Town of Southampton
A
The Conway School Graduate Program in Sustainable Landscape Design and Planning Fall 2013
A
A
Gallagher Hannan
10 affordable housing units total, 2 duplexes
Suitability Study for Proposed Affordable Housing Development
Housing Alternative #2: Two cluster developments incorporate attached rental housing and use the flattest areas of the site
*Red line indicates current topography.
10/22
G
B Limited parking (residents are encouraged to use community-shared cars and golf carts to navigate the
A
site’s steep slopes) allows for some cars to be kept near the entrances to the buildings. Patios provide a warm sunny place for residents to relax.
A
C Stairs lead down to woodland gardens, next to rocky overflow swales that move water downhill towards
E A parking court (16 cars) provides parking for residents’ cars and shared cars.
A’
F The lower cluster of buildings contains more residential units as well as a community center with gathering spaces and facilities for exercise, entertainment and artistic pursuits.
G A network of trails through native meadows and woodland gardens occupies the flat area (<10% slopes)
B
overlooking the intermittent stream.
B’
E
H A network of swales and infiltration basins retain and filter water, especially important with so many impermeable surfaces and dense groupings of buildings across the slope.
F
HO
H
LYO K
EW ATE R
*More research is necessary to determine what size and type of septic system would be appropriate for this type of development.
A-A’
Path
E
Attached units
Road Parking Swale and patio Covered walkway Covered walkway
B-B’
10 ft of 2% grade to move water away from the houses
Path
Path
LIN
Laurie Drive, Southampton, MA Client: Town of Southampton
D
etated swale that provides screening between buildings and driveway, in addition to moving and filtering water.
Alternative #3
C
LAURIE DRIVE
D A covered walkway allows easy wintertime access to the second cluster of attached units, next to a veg-
Suitability Study for Proposed Affordable Housing Development
infiltration basins during large storm events.
B
Infiltration basin
Parking lot (3% slope)
Path 50% vegetated slope
*Red lines indicate current topography.
Not for construction. Part of a student project and not based on a legal survey.
may be eligible for funding not available to small developments, according to Michelle Adaragh of HAP Housing.) The buildings have green roofs to decrease the amount of impermeable surface and aid in stormwater management.
The Conway School Graduate Program in Sustainable Landscape Design and Planning Fall 2013
A Attached units flank the driveway, acting as retaining walls. (Large developments of attached units, 35+,
Gallagher Hannan
Alternative #3: Multi--unit green community for elderly residents in a beautiful woodland setting is eligible for funding not available to smaller developments 35 + small affordable units for the elderly
11/22
Deciduous, small under-story tree. Distinctive striped bark and large, lobed leaves that turn yellow in the fall. Flowers are bright yellow in the spring.
Scarlet Oak Quercus Coccinea Deciduous, medium to large tree. Grows well on poor dry soils and slopes. Bright red leaves in the fall.
Low-Bush Bluebery Vaccinium angustifolium Low spreading deciduous shrub that grows well in well-drained acidic soils. Edible.
Eastern Red Cedar Juniperus virginiana Evergreen, small to medium tree. Commonly upright and columnar. Though plants can also be broad and bushy. Grows well in dry open woodlands, roadsides. Eastern Serviceberry Amelanchier Canadensis Deciduous, shrub or small tree. Beautiful white flowers in very early spring. Berries are edible.
Black-Eyed Susan Rudbeckia hirta
Switchgrass Panicum virgatum
Hayscented Fern Dennstaedtia punctilobula
Common plant with a yellow daisy-like flower. Grows in sandy and gravelly conditions. Grows well with little bluestem.
Perennial warm season bunchgrass. Can grow up to 9 ft. Grows well in sandy conditions.
Grows in colonies, forming a carpet. Found at the edge of woods and in open woods.
Heath Aster Aster ericoides
Tickseed Coreopsis lanceolata
Herbaceous perennial with white daisy-like composite flower heads that appear in later summer through fall.
Herbaceous perennial with yellow flowers 1-1.5 inches across. Tickseed grows in small clumps but can spread and form large colonies.
Sassafras Sassafras albidum
Echinacea Echinacea pallida
Northern Bush Honeysuckle Diervilla lonicera
Deciduous, small to medium tree. Plant closer to the forest edge as it needs some sun. Sassafras roots provided the original flavoring for root beer. Fall color is bright yellow to red.
Herbaceous perennial with pale purple flowers. Grows well in sandy dry soils. Sometimes used for medicinal purposes.
www.provant.be
Usually a shrub, but can be a small tree. Fall color is yellow, and unusually it flowers in winter.
Sweetfern Comptonia peregrina Deciduous shrub, grows to 5 ft, with a sweet smell when crushed. Loves sandy, gravelly sites. Nitrogen fixer.
plants.bachmanslandscaping.com
Striped Maple Acer pensylvanicum
www.hort.uconn.edu
Woodland plants to enhance habitat and add interest for humans
Deciduous, small tree. Pale whitish trunks and fluttering green leaves. Groves can be all part of one plant with a common root system, and all turn brilliant gold together in the fall.
Flowering ornamental perennial with a purple flower. Food plant for moths.
American Witch-hazel Hamamelis virginiana
pendulousplants.com
Quaking Aspen Populus Tremuloides
Upright clumps of grass with tinge of blue at the base. Especially beautiful in fall, with its bronze-orange color.
Deciduous shrub with a maximum height of 4 ft. Flowers in July and August with a deep red fall foliage.
*unless otherwise labeled, drawings are from The Sibley Guide to Trees and photos are from Wiki commons
Not for construction. Part of a student project and not based on a legal survey.
Ornamental grown primarily as a ground cover. Could be attractive near trails at the woods edge or in the woods.
Blazing Star Liatris
Laurie Drive, Southampton, MA Client: Town of Southampton
Deciduous, small tree. A common pioneer species in disturbed soils, especially sandy well drained hillsides. White-barked, but non peeling.
Little Bluestem Schizachyrium scoparium
The Conway School Graduate Program in Sustainable Landscape Design and Planning Fall 2013
Barren Strawberry Waldsteinia fragariodes
Suggestions for ornamental plants around the houses
Gallagher Hannan
Grey Birch Betula populifolia
Plantings for areas away from the houses cleared during development, to create an open meadow in sandy, gravelly conditions
Suitability Study for Proposed Affordable Housing Development
Woodland edge planting to increase diversity and habitat, create a successional community, and build a buffer to preserve the integrity of the forest
Plant Palettes
Plant native plants that tolerate sandy soils, to build a low-maintenance landscape and provide views, invite exploration, create habitat and increase the overall health of the forest.
12/22
Carefully creating a network of swales and infiltration basins along impermeable surfaces will retain, control and filter water.
22’
2’ swales
*an example of a hammerhead firetruck turnaround can be found in Seattle Fire Code in Appendix A
The driveway should be a minimum of 22’, with room for 2 ft swales on either side to move polluted water to infiltration basins where it can be filtered.
Some swales are just open grassy channels where water can collect and percolate.
www.horsleywitten.com
There are many types of infiltration basins and swales (swales move water, infiltration basins retain and filter water). Careful research and planning is necessary to determine which ones are appropriate for specific circumstances. Native plantings can help slow and filter water, and also add visual interest to swales and basins.
Others filter water through layers of permeable soils and An example of an attractive infiltration sand and into pipes to basin by the Horsley Witten Group. take it back into the stormwater system. *Information on infiltration basins and swales from Design of Stormwater Filter Systems from the Center for Watershed Protection (cwp.org).
Not for construction. Part of a student project and not based on a legal survey.
Fill removed and streambank restored
Groundcover: Virginia Wildrye (Elymus virginicus) Deertongue (Panicum clandestinum) Creeping Red Fescue (Festuca rubra) Switchgrass (Panicum virgatum) Fox Sedge (Carex vulpinoidea) Partridge Pea (Chamaecrista fasciculata) Autumn Bentgrass (Agrostis perennans)
Gallagher Hannan
Laurie Drive, Southampton, MA Client: Town of Southampton
Shrubs: Lowbush Blueberry (Vaccinium angustifolium) Silky Dogwood (Cornus amomum)
The Conway School Graduate Program in Sustainable Landscape Design and Planning Fall 2013
Some possible vegetation for stream-front stabilization plantings
Suitability Study for Proposed Affordable Housing Development
Stream bank restoration involves regrading the slopes on either side of the stream, which are currently almost 100% slope, and restoring them to 30% slopes. After the slopes are regraded, burlap or rip-rap is placed down and vegetation is planted through the fabric to stabilize the soil. The stream would then be much healthier and more accessible, and would not continually undercut the base of the entire site.
Managing Stormwater & Streambank Restoration
Restoring the stream bank by removing fill and replacing cul-de-sac with a “hammerhead” will reduce serious erosion problems and create a beautiful and more accessible area for residents to enjoy.
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Community Land Trust
A community land trust is an independent nonprofit corporation that develops and stewards affordable housing on behalf of the community. Houses are kept affordable in perpetuity and the nonprofit retains the power to make decisions about land use and home repairs. For more information visit www.cltnetwork. org.
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Next steps to determine development suitability •
Funding for Green Building
Funding is available at the national, state and local levels for government organizations and non profits interested in constructing green buildings. For more information visit www.epa.gov/greenbuilding.
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1.5 ACRES of flat pasture land with great southern exposure sits in a sliver behind a line of trees to the south of the site. Perhaps in addition to granting permission for a right-of-way, the farmer would be willing to sell this land to the Town.
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A view by the eastern boarder of the site. This beautiful established forest should be preserved as much as possible.
Market study to determine what the demand for housing is, and what types of housing is desired. Is this location too remote for elderly housing? The Southampton Council on Aging already provides van rides for seniors; could public transportation serve this site? Consult with different non-profits, to discover what kind of funding is available. Consider building rental units instead of units to buy. For more information on available funding see the Department of Housing and Community’s Development Qualified Allocation Plan. Consult with neighbors to determine if adjacent land is available as a right-of-way, and/or for an expansion of the developable area. Continue to re-evaluate new information about development opportunities and/or site conditions. If a professional survey shows that the slopes on top of the hill actually are >10%, or the farmer refuses to sell the Town a right-of-way, consider putting this land into open space conservation instead of developing it.
Not for construction. Part of a student project and not based on a legal survey.
Open space around developments is put into conservation, and can be open to the public. For more information visit www.landscope.org
Professional survey to determine exact topography. More perc and soil tests to determine if the bedrock is as far beneath the surface at the top of the hill as it is down by the stream. According to ecologist Bill Latrell (Valley Environmental Group), the Jurassic Red Sandstone is likely closer to the surface in certain areas. It will be necessary to discover where those areas are before septic systems, and then houses, can be designed and built. Wetland delineation plan to discover if the areas by the river are considered wetlands, and are regulated.
Laurie Drive, Southampton, MA Client: Town of Southampton
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The Conway School Graduate Program in Sustainable Landscape Design and Planning Fall 2013
Conservation Development
Next steps to determine site conditions
Gallagher Hannan
.8 ACRES of what appears to be buildable land to the north of the site belongs to a property that was foreclosed upon and bought in July 2013. The land is cut off from the owner’s house (sited along Valley Road) by very steep slopes. Perhaps the new owner would be willing to sell this sliver of land to the Town.
Are there development strategies that would make the project even more green?
Suitability Study for Proposed Affordable Housing Development
Is there room to expand the development into adjacent lots?
Questions That Remain & Next Steps
Many further questions remain about this site and its suitability for an affordable housing development.
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