Single Jurisdiction Hazard Mitigation Plan
Town of Londonderry, Vermont
Prepared for:
Town of Londonderry, VT
100 Old School Street, South Londonderry, VT 05155
Bennington County
Prepared by:
Windham Regional Commission
139 Main Street, Suite 505, Brattleboro, VT 05301
(802) 257-4547
DRAFT DATE: December 3, 2012
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
Table of Contents – re do page #s
.................................................................................................................... Pg
INTRODUCTION AND PURPOSE ............................................................................. 3
TOWN PROFILE ........................................................................................................ 3
GEOGRAPHY ............................................................................................................ 3
PREQUISITES
Adoption by the Local Governing Body ........................................................... 5
Multi-Jurisdictional Plan Adoption ................................................................... 6
Multi-Jurisdictional Planning Participation ....................................................... 6
PLANNING PROCESS
Documentation of the Planning Process ......................................................... 7
RISK ASSESSMENT
Identifying & Profiling Hazards ........................................................................ 8
Assessing Vulnerability: Overview .................................................................. 12
Assessing Vulnerability: Addressing Repetitive Loss Properties ..................... 13
Assessing Vulnerability: Identifying Structures ................................................ 14
Assessing Vulnerability: Analyzing Development Trends ................................ 14
Multi-Jurisdictional Risk Assessment .............................................................. 14
MITIGATION STRATEGY
Local Hazard Mitigation Goals ........................................................................ 15
Identification and Analysis of Mitigation Actions .............................................. 15
Identification and Analysis of Mitigation Actions: NFIP Compliance ................ 15
Implementation of Mitigation Actions .............................................................. 16
Multi-Jurisdictional Mitigation Actions.............................................................. 17
PLAN MAINTENANCE PROCESS
Monitoring, Evaluating, and Updating the Plan ............................................... 18
Incorporation into Existing Planning Mechanisms ........................................... 18
ATTACHMENTS
Public participation documentation ................................................................. 20
Maps (Attached as pdf files) ........................................................................... 20
_______________________________________________________________________
Page 2
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
INTRODUCTION AND PURPOSE
The purpose of this plan is to assist the Town of Londonderry in identifying all of the hazards
facing the town and to identify strategies to begin reducing risks from identified hazards.
Hazard mitigation is any sustained action that reduces or eliminates long-term risk to people and
property from natural and human-caused hazards and their effects. Based on the results of
previous Project Impact efforts, FEMA and state agencies have come to recognize that it is less
expensive to prevent disasters than to repeatedly repair damage after a disaster has struck. This
plan recognizes that communities have opportunities to identify mitigation strategies and
measures during all of the other phases of Emergency Management – preparedness, response
and recovery. Hazards cannot be eliminated, but it is possible to determine what the hazards are,
where the hazards are most severe and identify local actions that can be taken to reduce the
severity of the hazard.
Hazard mitigation strategies and measures alter the hazard by eliminating or reducing the
frequency of occurrence, averting the hazard by redirecting the impact by means of a structure or
land treatment, adapt to the hazard by modifying structures or standards or avoid the hazard by
stopping or limiting development, and could include projects such as:












Flood-proofing structures
Tying down propane/fuel tanks in flood-prone areas
Elevating furnaces and water heaters
Identifying and modifying high traffic incident locations and routes
Ensuring adequate water supply
Elevating structures or utilities above flood levels
Identifying and upgrading undersized culverts
Proactive land use planning for floodplains and other flood-prone areas
Proper road maintenance and construction
Ensuring critical facilities are safely located
Establish and enforce appropriate building codes
Public information
WINDHAM REGION GEOGRAPHY
The Region includes the towns of Athens, Brattleboro, Brookline, Dover, Dummerston, Grafton,
Guilford, Halifax, Jamaica, Londonderry, Marlboro, Newfane, Putney, Rockingham, Stratton,
Townshend, Vernon, Wardsboro, Westminster, Whitingham, Wilmington, and Windham in
Windham County; the neighboring towns of Readsboro, Searsburg, and Winhall are in
Bennington County; and Weston is in Windsor County. Situated in Vermont's southeastern
corner, the Region is bordered by Bennington and Windsor Counties to the west and north,
Massachusetts to the south and New Hampshire to the east. The Region’s area is nearly 600,000
acres, or over 900 square miles.
The topography is generally hilly, with steep slopes on the river valleys on the east slopes on the
Green Mountains. The Connecticut River Valley contains areas of relatively flat and gently rolling
land. The Green Mountains form the western edge of the region with a landscape of ridges and
mountain peaks with narrow stream valleys. Stratton Mountain is the highest point in the region at
3,936 feet. The lowest point is along the Connecticut River in Vernon at 200 feet.
In addition to the Connecticut, other major rivers of the region are the Deerfield, Green, North,
Saxtons, West, and Williams, all tributaries of the Connecticut. There are two major flood control
reservoirs on the West River, Ball Mountain and Townshend, and two major storage reservoirs for
hydropower generation on the Deerfield River, Somerset and Harriman.
_______________________________________________________________________
Page 3
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
LONDONDERRY GEOGRAPHY & TOWN PROFILE
Londonderry is the commercial hub for the surrounding towns of Weston, Landgrove, Windham,
Jamaica, and Winhall. The shopping center at the intersection of Rt. 100 and Rt. 11 includes a
gas station, convenience store and restaurant which are heavily used by travelers and locals.
Londonderry is also the hub for accessing several ski resorts; Magic Mountain is in town, Stratton
ski resort, Bromley and Okemo are nearby. During winter months there is greater traffic flow due
to people traveling to and from these resorts. Roughly half of the Grand List is vacation homes.
Londonderry’s landscape retains important vestiges of the town’s agricultural heritage. Working
farmland not only provides a source of local food and fiber, but also helps define the town’s
scenic landscape, in itself an important economic asset.
Londonderry is built along the main stem of the West River and its major tributaries. Significant
timber resources exist in town, including hard and soft wood stands and sugar maple groves.
Local forests provide quality habitat to a range of species. Wildlife that may be found in
Londonderry includes deer, bear, bobcat, fisher, moose, turkey, ducks, geese, blue heron, ruffed
grouse, woodcock, otter, beaver, bass, trout, pickerel, fishers, and others.
The town’s water resources include the West River, the Winhall River, Lowell Lake, Lily Pond and
Gale Meadows Pond, as well as various wetlands and floodplains. The aforementioned waters all
are included in the West River Watershed. The West River – which drains into the Connecticut
River and on into the Atlantic Ocean near Long Island Sound –has been identified as a nationally
important fish and wildlife habitat primarily due to the potential for Atlantic salmon restoration.
Londonderry is surrounded by several smaller villages. Peru, Landgrove, Windham and Andover
are primarily residential communities with some farming, forestry and inns. Winhall and Jamaica
have village centers and businesses serving the ski industry. Weston is a residential community
with a village center and green along state Route 100 that sustains tourism year round.
Development trends in Londonderry, surrounding towns and most of southern Vermont have
been strong for several years, with marked increase in land subdivision, new home construction,
and real estate sales at elevated prices, primarily for vacation homes. As a larger town that
provides a variety of essential services, Londonderry is more significantly impacted than
surrounding towns by regional developments such as the Stratton Mountain complex and other
tourist activities. The Town Plans in the Mountain Valley region are similar and compatible with
each other. Londonderry maintains contact with neighboring planning commissions to coordinate
and consult about issues that may cross town lines and also relates to other towns in the region
by working with the Windham Regional Commission.
The map on the following page is the most current from their Town Plan.
_______________________________________________________________________
Page 4
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
_______________________________________________________________________
Page 5
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
PREQUISITES
Adoption by the Local Governing Body
Certificate of Adoption
Town of Londonderry, VT
Board of Selectmen
A Resolution Adopting the Single Jurisdiction Hazard Mitigation Plan, for
the Town of Londonderry, VT
WHEREAS, the Town of Londonderry, VT has worked with the Windham Regional Commission
to identify natural hazards, analyze past and potential future damages due to natural disasters,
and identify strategies for mitigating future damages; and
WHEREAS, The Town of Londonderry, VT Hazard Mitigation Plan analyzes natural hazards and
assesses risks within the community; and
WHEREAS, the Town of Londonderry, VT Hazard Mitigation Plan recommends the
implementation of action(s) specific to the community to mitigate against damage from natural
hazard events; and
NOW, THEREFORE BE IT RESOLVED that the Town of Londonderry, VT adopts the Hazard
Mitigation Plan for the Town of Londonderry, VT.
Duly adopted this _____________ day of ________________________________________.
date
month, year
Board of Selectmen:
___________________________________________________
name, Chair
___________________________________________________
name
___________________________________________________
Name
ATTEST
___________________________________________________
name, Town Clerk
_______________________________________________________________________
Page 6
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
Planning Participation
Town residents who took part in the planning process for developing the Hazard Mitigation Plan
for Londonderry tend to be affiliated with more than one association for the town. Most of the
people on the committee have lived in Londonderry for most of their lives. Since the town of
Londonderry did not have an EMD (Emergency Management Director) at the time of the Tropical
Storm Irene event in August of 2011, Kevin Beattie, the town Selectman acted as the EMD.
Because of the difficulties that were realized by not having a designated EMD, the town is
planning to establish one and have them trained. In rural areas of Vermont, it is typical that
people who are most interested in the safety, health and welfare of their community will preside
on more than one board, and for example, hold the role of Fire Chief, or school teacher, or be a
small business owner, in addition to owning personal property in the town. Therefore, although
the meeting may not have as many in attendance, as in a more populated community, those
present at the meeting are representing not only a variety of roles, but many roles that would be
held by individuals in a more populated town or city. The matrix below lists the members on the
hazard planning team.
The ways in which Londonderry has included other towns in the planning process of this plan has
been by having mutual aid for Fire and emergency through Southwestern New Hampshire, and
the adjacent towns of Weston, Windham, Peru, Winhall and Jamaica. During emergency
situations that require collaborative efforts with adjacent jurisdictions, an ad hoc group will form to
assess daily status of roads, bridges and other infrastructure. Londonderry has hosted meetings
whereby they invited the Fire Departments, Selectboard members, and police from all the
adjacent towns to plan for emergency response. The town included input from their neighboring
town of Winhall in this planning process by having 1st responders from Winhall on their
emergency committee.
The Town of Londonderry also provided their hazard plan as an attachment to an email to the
Town Managers/Administrators/Officials of Weston, Windham, Winhall, Jamaica and Peru asking
that they review the plan for any additional comments. If adjacent towns provide comments, those
comments will be added in an attachment to this plan during the review process.
Committee Member
Affiliations
Home
Steve Prouty
Selectman , Mailman, Town Health Officer
Londonderry
James Ameden
Selectman, Fire Chief
Londonderry
Peter Pagnucco
Selectman
Londonderry
Wayne Blanchard
Road Foreman
Londonderry
Kevin Beattie
Selectman, Londonderry Rescue Squad
Londonderry
James H. Twitchell
Town Clerk
Londonderry
Jeff Whitesell
Police Department
Winhall
Dinah Reed
Windham Regional Commission Assistant
Planner
Brattleboro
_______________________________________________________________________
Page 7
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
PLANNING PROCESS
Documentation of the Planning Process
The Town of Londonderry pulled together a committee of town’s people in October 2011 to
include representatives from the Selectboard, Post office, Road Crew and Town Officials to
discuss the vulnerabilities and risks of all hazards to Londonderry. Viewpoints from adjacent
communities were taken into consideration by staff with the Windham Region Commission (WRC)
as they have been working concurrently with adjacent towns on their hazard mitigation plans.
Other town and state agencies such as the conservation commission were invited to participate in
the planning process. An additional meeting took place on December 15 to specifically discuss
hazard mitigation strategies and action items for the town.
The Town of Londonderry will continue to work with the Windham Regional Commission to
monitor, evaluate, and update the plan throughout the next 5 year cycle. A review of the plan will
take place each year by the emergency planner at the Windham Regional Commission along with
the town’s emergency planning committee, led by the EMD, to update the plan after any FEMA
disaster declaration as well as any funding received from FEMA, to record any hazard related
events, or to determine if the town is interested in applying for grant funding. Additionally, the
emergency committee will assess ongoing hazard mitigation work and coordinate among
stakeholders to identify structures and engineering projects that can help mitigate future
hazardous events; e.g. bridge and culvert replacements, road replacements and grading, as well
as any repetitive loss structures that may be in the Special Flood Hazard Area as identified on
FEMA Flood Maps (e.g. FHBM and FIRM maps). Additionally, all plan review meetings will be
publicized and open to the public. The plan and any proposed revisions will be on the jurisdictions
website with information on how the public can direct questions/comments to the planning team.
Public Participation
The Londonderry Hazard Mitigation Plan was made available for public comment by posting it to
the Town of Londonderry website. A hard copy was made available at the Town Office, Library
and Fire Department. Although the town made the plan easily available, no comment was on the
plan was made by the public. The plan will also be made available at Town Meeting in March,
2012.
 Plan is posted on the Town website for viewing. http://www.londonderryvt.org/index.html
The following hazard mitigation planning meetings were held:
 October 5, 2011, 6:00– Londonderry Town Offices
 December 15, 2011 – Londonderry Town Offices
 February 22, & April 18, 2012 – phone conversation with Emergency Management
Director
 Any new public participation??
 Explain the Opportunity provided for public participation and the Means.
 Be descriptive. How was the public involved, explain resources for information provided,
such as ANR?, NRCS?, DEC staff?, VT F&W?, etc. Additionally – add this info to the
planning process section – how did any of these staff from State Agencies inform your
planning process?
_______________________________________________________________________
Page 8
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
RISK ASSESSMENT
The risk assessment portion of a Multi-hazard Mitigation Plan contributes to the decision-making
process for allocating available resources to mitigation projects. 44 CFR Part 201.6(c)(2) of
FEMA’s mitigation planning regulations requires local municipalities to provide sufficient hazard
and risk information from which to identify and prioritize appropriate mitigation actions to reduce
losses from identified hazards.
Identifying and Profiling Hazards – The community has identified and focused
mitigation action items on the following hazards; Flood, Winter Storm/Ice Storm and High
Wind events. It should be noted that Earthquake, Landslide, Avalanche and Extreme
Heat, Drought, Wildfire and Tornado/Microburst, are profiled in the State All Hazard
Mitigation Plan. This local plan will only profile and analyze natural hazards that have
been deemed as having a “highly likely” impact on the Town of Londonderry.
In the “Assessing Vulnerability: Overview” section on page X, a “Highly Likely” occurrence is one
that has a 100% probability of occurring every year. The methodology is fully explained in that
section.
The following hazards include a narrative explaining Location/Geographic Area and Extent
(magnitude or severity), Probability, and discussion of Past Occurrences of all natural hazards
that affect the planning area.
Note: According to the NOAA website zero WILD & FOREST FIRE event(s) were reported in
Windham County, Vermont between 01/01/2000 and 08/31/2011. Source:
http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~storms
REGIONAL FLOODING
The Vermont Flood of 1927 was the deadliest natural disaster in the history of the State; eightyfour people were killed with over $28 million in property damage. The Spring Floods of 1936,
which had an affect on all of New England, caused $113 million in damage, killed 24 people and
made 77,000 people homeless. During this flood alone, the main street of Hooksett, New
Hampshire was 18 to 20 feet underwater.
During 1978, flooding occurred throughout New England causing millions of dollars in damage.
In 1996, flooding ravaged communities in northern New England resulting in significant damage
and a Presidential Declaration of Emergency.
LOCAL FLOODING
Description and Geographic Area of Hazard
Flash floods typically occur during summer when a large thunderstorm or a series of rain
storms result in high volumes of rain over a short period of time. Higher-elevation drainage
areas and streams are particularly susceptible to flash floods. Flash floods are likely in
Londonderry, and potential damage to Route 100 or Route 11 could limit access to town, as
they are the major transportation corridors through the community. Some of the highest
hazard areas associated with flash floods are areas along Route 11 and the West River
floodplain corridor in the two village areas. Other areas of concern during flooding events are
homes located along brooks that are subject to flash floods during brief heavy rain events.
Areas where flooding typically occurs are Flood Brook, West River (biggest in magnitude),
Tannery Brook (most re-occurring), Cook Brook, Boynton Road (headwaters are in Andover,
starts as a beaver pond).
Extent
_______________________________________________________________________
Page 9
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
In the latest Tropical Storm Irene event of August 2011, a total of approximately 8 inches of rain
fell in a timeframe of 12 hours, causing the West River to rise approximately 12-15 feet above
the normal flow at river bottom. The flash flood water caused fluvial erosion of the shoreline and
specifically trees, boats, propane tanks, dumpsters, 2 U-Haul trucks and one porch that were in
the floodway were washed down the river, and damaging homes in South Londonderry. Main
Street had 6 feet of standing floodwater for 12 hours. A commercial building on Main Street had
floodwater measuring 5 feet on the ground floor. Roads and bridges were washed out all over
town.
Probability
The emergency committee for the Town of Londonderry states that flooding is highly likely as a
result of thunderstorms, or spring snow melt. Probability of flooding is also very high if heavy
rain falls on saturated grounds. Need to elaborate on probability based on studies (state-wide)
etc. SGA’s, FEH, etc.
Past Occurrences
Need annual occurrences that are local, small, not necessarily warranting an HMGP – not just
Federally Declared issues.
August 28, 2011 - The latest Presidentially Declared Disaster, DR-4022, resulted from Tropical
Storm Irene. Tropical Storm Irene tracked north northeast across eastern New York and
western New England during Sunday, August 28th, producing widespread flooding, and
damaging winds across the region. Irene tracked from a position over New York City around 8
AM EST Sunday, to approximately 65 miles south of Rutland, VT at 4 PM EST. The greatest
impact from Irene across southern Vermont was due to heavy to extreme rainfall, which resulted
in catastrophic flooding. Rainfall amounts generally averaged 4 to 8 inches. Much of the rain
which fell occurred within a 12 hour period, beginning early Sunday morning, and ending
Sunday evening. This heavy to extreme rainfall resulted in widespread flash flooding and river
flooding across southern Vermont. Strong winds also occurred across southern Vermont, with
frequent wind gusts of 35 to 55 mph, along with locally stronger wind gusts exceeding 60 mph.
The strongest winds occurred from the north to northeast during the morning hours, then from
the west to northwest during Sunday evening. The combination of strong winds, and extremely
saturated soil led to numerous downed trees and power lines across the region. This also
resulted in widespread long duration power outages. In particular, the approximate number of
customers affected by power outages included: Windham County 18,000.
April 15-21, 2007 - A flooding event occurred which was associated with flash floods and
inundation flooding over a period of several days in the spring. Rain and snow caused damage
to roads and utility lines across Windham County and Londonderry. Across, the State, nearly
3.6 million dollars was obligated as part of the FEMA Public Assistance Program. While it is not
normal for the Town to receive this type of damage from severe flooding and thunderstorms on
an annual basis, road washouts and culvert repairs from these associated events have ranged
in the ballpark of $200,000 to $400,000.
August 12 – September 12, 2004 - A severe period of flooding and thunderstorms engendered
Presidential Disaster Declaration DR – 1559.
Aug 3, 2003 - A slow moving storm over Windham County produced doppler radar estimated
rainfalls of 3 to 4 inches in about four hours time. The torrential rains took a toll, washing out
roads in the city of Londonderry. County Highway 121 was washed out in the Town of
Windham. Massive flooding occurred in the neighboring town of Grafton at the base of Fire
Pond and Hinkley Brook roads, where water, debris and mud washed those roads out. The
raging debris knocked a house off its foundation and damaged several other ones. This was the
same area affected by the infamous Flood of 96 which was even more severe. Heavy rains also
washed away a small covered bridge in Grafton.
_______________________________________________________________________
Page 10
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
1976, 1978 – Flooding occurred according to historical knowledge stated by towns people.
June 1973 – Inundation flooding in town, affected village because didn’t recede as fast. Town
lost two large culverts on Winhall Hollow Road and lost Cross Road Bridge, all of
Thompsonburg Road was washed out, which runs along a brook.
Sources used
Weather Advisory from Albany Weather Service, Press Releases from VEM, local town
knowledge.
http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~307631
REGIONAL SEVERE WINTER STORM
The Region has a long history of severe winter storms and blizzards and usually experiences at
least one or two Nor’easters each year with varying degrees of severity. There have been 114
winter storms in the Region since March 1960 that have resulted in $5,133,582.00 in property
damages. A typical event begins as a low-pressure system that moves up the Atlantic Coast on
a December morning and into the Canadian Maritimes dumping heavy snow across parts of
Vermont. Snow typically begins in the morning and then changes over to sleet and rain in the
valleys during the day, and then changes back to snow during the evening. Snowfall
accumulations are generally three to six inches in the valleys and 6 to 12 inches in the
mountains.
LOCAL WINTER STORM / ICE STORM
Description and Geographic Area of Hazard
Winter storms, with snow, ice and freezing temperatures in varying combinations, are fairly
commonplace in Londonderry and occur town wide. Heavy wet snows of early fall and late
spring, as well as ice storms, often result in loss of electric power, leaving people without
adequate heating capability. The other threat from these storms is downed trees, resulting in
power failures and impassable roads or driveways.
Damage from heavy snow and ice storms can vary depending upon wind speeds, snow or ice
accumulation, storm duration, and structural conditions (such heavy snow and ice
accumulation on large, flat roofed structures). The assessed value of all residential and
commercial property is ($ 375,646,275 ) Assuming a range of town-wide damage of 1% to 5%,
a heavy snow or ice storm could result in ($3,756,462 ) to ($18,782,313 ) of total damage.
 Power Failure
Power failure is a common condition that is typically the result of power lines damaged by
high winds or heavy snow/ice storms and can occur anywhere in town. The higher
elevation locations in town are most susceptible to power failures. Power failures may also
result from disruptions in the New England or national power grid, as indicated by the
widespread power outages in 2003. Dead or dying trees in close proximity to power lines
pose a particular threat for power failure. Potential loss estimates are difficult to predict for
power failures, which typically are isolated in geographic areas and short in duration.
Therefore, they often have only minimal impact to people and property. Power failures
usually result in minor inconveniences to residents; however, longer duration events might
result in the loss of perishable items and business losses. Power outages in winter months
could result in the loss of home heating, bursting water pipes and resulting structural water
damage.
Extent
The snowfall of winter 2010-2011 exceeded 120 inches in southeast VT. Typical snowfall in
southeast VT ranges from 60-65 inches. Snow and ice come every year to the town where the
extent is typically fairly high given we are in the Northeast corner of the continent. It depends on
how fast it comes and whether or not it melts off in between snowfalls as to whether it not it
poses a threat to the community. The Town typically receives 2-3 feet of snowfall every year.
_______________________________________________________________________
Page 11
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
Probability
The emergency committee in the Town of Londonderry deems winter storm / ice storm as
highly likely to happen every year.
Past Occurrences
Need local, small, annual occurrences – not just Federally Declared issues.
Mar. 7, 2011 - A cold front moved gradually southeastward across the region during the day
Monday, March 7th, as a wave of low pressure moved northeastward along the boundary. To
the south of the boundary, it was mild as the area was in the warm sector of the low pressure
system. The storm tapped into both Atlantic and Gulf moisture, resulting in heavy rainfall of 1
1/2 to 3 1/2 inches across southern Vermont Sunday, March 6th, into Monday, March 7th
before the precipitation transitioned to a wintry mix then snow early Monday morning. The
heavy rainfall, combined with runoff from snowmelt due to the mild temperatures, resulted in
flooding of rivers, streams and creeks, mainly from the formation of ice jams. Damage
estimates are unknown.
December 2008 - An Ice Storm crossed the region causing widespread downed trees and
power outages in Windham County. The total cost of damages across the region crossed the
one million dollar threshold which allowed for a Presidential Disaster Declaration DR-1816.
Damage across the region mostly consisted of roads being blocked for short periods of time
due to downed trees and utility lines. Thousands lost power for varying lengths of time and
several shelters were opened in Windham County. Compared to neighboring southern New
Hampshire communities, Londonderry fared relatively well from the damage inflicted by the
Ice Storm.
January 1998 – An ice storm hit the region and most of upstate New York and Vermont were
out of power for a month. Two skiers were lost and it took a region wide effort to find them.
Trees were brought down by the heavy ice, all over town.
November 22, 1997 - A low pressure system south of Long Island on November 22, 1997
produced heavy wet snow across southern Vermont. Snowfall averaged 4 to 8 inches in
Windham County. The heavy wet snow downed trees and power lines, which produced
scattered power outages.
October 1987 – A sudden snow storm of approximately 1 foot of heavy snow brought down
trees all over town.
Sources used
Local knowledge
http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~307631
REGIONAL HIGH WIND / TROPICAL STORM / HURRICANE
Windstorms are high-wind events that are sufficient enough to cause damage to property and
can occur at anytime during a year. These include high winds in conjunction with a
thunderstorm and high winds that sweep through the Region after the passage of a weather
front. During the past forty-six (46) years, the Region has had seventy (70) windstorms that
have caused significant damages.
LOCAL HIGH WIND / TROPICAL STORM / HURRICANE
Description and Geographic Area of Hazard
High wind events are highly likely in Londonderry, with the potential for limited resulting
damage. The most likely local threats for high winds are from nor’easters, hurricanes,
downbursts or wind shear. Trees downed by high winds can block roads, and down power and
_______________________________________________________________________
Page 12
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
communications lines. Mobile home parks and houses on ridge lines are at greater risk from
wind damage. Most high winds events in Londonderry have resulted in damage from downed
trees and power lines.
Extent
The greatest extent of high winds on record for the past decade in and near the Town of
Londonderry was during the high wind event in September 2010 when the region experienced
50-60 mph winds. The wind event as a result of Tropical Storm Irene were also locally as great
as 60 mph at times. Based on past experience, the Town of Londonderry would anticipate an
equally significant wind event to occur any given year. Extent/magnitudes of Hurricanes and
Tropical Storms are ranked using the Saffir-Simpson Scale in the Western Hemisphere, as
follows: CAT1=74-95 mph winds, CAT2=96-110 mph winds, CAT3=111-130 mph winds,
CAT4=131-155 mph winds, Tropical Storm=39-73 mph winds, Tropical Depression=0-38 mph
winds.
Probability
The emergency committee for the Town of Londonderry states that high winds is a highly likely
natural hazard event that will occur any given year.
Past Occurrences
Need small, local, annual occurrences – not just Federally Declared issues.
The latest Presidentially Declared Disaster, DR-4022, resulted from Tropical Storm Irene in
August 2011. Tropical Storm Irene tracked north northeast across eastern New York and
western New England during Sunday, August 28th, producing widespread flooding, and
damaging winds across the region. Irene tracked from a position over New York City around 8
AM EST Sunday, to approximately 65 miles south of Rutland, VT at 4 PM EST. The greatest
impact from Irene across southern Vermont was due to heavy to extreme rainfall, which resulted
in catastrophic flooding. Rainfall amounts generally averaged 4 to 8 inches. Much of the rain
which fell occurred within a 12 hour period, beginning early Sunday morning, and ending
Sunday evening. This heavy to extreme rainfall resulted in widespread flash flooding and river
flooding across southern Vermont. Strong winds also occurred across southern Vermont, with
frequent wind gusts of 35 to 55 mph, along with locally stronger wind gusts exceeding 60 mph.
The strongest winds occurred from the north to northeast during the morning hours, then from
the west to northwest during Sunday evening. The combination of strong winds, and extremely
saturated soil led to numerous downed trees and power lines across the region. This also
resulted in widespread long duration power outages. In particular, the approximate number of
customers affected by power outages included: Windham County, 18000.
Sept. 30, 2010 - The combination of an intensifying low pressure system moving northward
along the east coast and high pressure off the New England and mid Atlantic Coast created a
very strong pressure gradient across the region. Strong and gusty southerly winds developed as
the low approached during Thursday September 30th. Winds gusts of up to 50 to 60 mph
occurred across southern Vermont. This event continued through October 1st, 2010 bringing
very heavy rainfall to the area. Storm total rainfall of 3 to 6 inches occurred across southern
Vermont resulting in widespread urban and small stream flooding.
May 2, 2002 - $20K in property damage - The gradient between a high pressure center in the
Ohio Valley, and deep low pressure over eastern Canada, produced a marginally high wind
event across high elevations of southern Vermont during the midday hours of May 3. Many
trees and power lines were reported blown down across the county. Over 1,000 customers were
temporarily without power in southern Vermont as a result of the wind.
Mar. 10, 2002 - $30K in property damage - The pressure gradient between deep low pressure
over Ontario, and high pressure off the southeast coast, produced a strong southerly flow
across southern Vermont on the evening of March 9. Then, a strong cold front moved across
_______________________________________________________________________
Page 13
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
the region shortly after midnight, early on March 10th. A line of showers and embedded
thunderstorms accompanied the front. Strong winds ahead of and along the front produced
some damage across Windham County. Law enforcement personnel reported a large number
of trees and power lines down throughout the county.
Jul 20, 1996 - $10K property damage - An unusually intense low pressure system tracked
across the northern Great Lakes to Quebec, Canada during July 19 and 20. The system
generated strong northwest winds, which downed trees and power lines over parts of Windham
County in southern Vermont.
Feb. 24, 1996 - $30K in property damage - A rapidly deepening low pressure system moved
from southern New Jersey northeast to northern Maine by the morning of February 25. This
system brought damaging winds to southern Vermont including Windham counties, which
downed many trees across the area and produced scattered power outages.
Jan 19, 1996 - $20K in property damage - An intense area of low pressure located over the MidAtlantic Region on Friday morning January 19th produced damaging winds across southern
Vermont. This storm was associated with a strong southerly flow which resulted in scattered
reports of downed trees, limbs and power lines.
Sources used
http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~ShowEvent~307631
Knowledge based on reports from locals living in the town for over 30 years.
Assessing Vulnerability: Overview
Methodology
A vulnerability analysis for each community begins with an inventory of possible natural hazards
and an assessment of the risk that they pose. These are the questions to be answered. What
hazards can affect your community? How bad can it get? How likely are they to occur? What will
be affected by these hazards? How will these hazards affect you? The magnitude (percentage of
the community affected) of the impact of the hazard can be classed as follows:




Negligible: < 10% of properties damaged/Minimal disruption to quality of life.
Limited: 10% to < 25% of properties damaged/Loss of essential facilities/services for up
to 7 days/few (< 1% of population) injuries possible.
Critical: 25% to 50% of properties damaged/Loss of essential facilities/services for > 7
days < 14 days/Major (< 10% of population) injuries/few deaths possible.
Catastrophic: > 50% of properties damaged/loss of essential facilities/services for > 14
days/Severe (> 10% of population) injuries/multiple deaths possible.
The frequency of occurrence (Likelihood) is classified as shown:
 Unlikely: < 1% probability in the next 100 years.
 Possible: 1% to 10% probability in the next year, or at least one chance in the next 100
years.
 Likely: 10% to 100% probability in the next year, or at least one chance in the next 10
years.
 Highly Likely: Near 100% probability in the next year.
Additionally, seasonal patterns that may exist are considered, what areas are likely to be affected
most, the probable duration of the hazard, the speed of onset (amount of warning time taking into
consideration the existing warning systems).
The combination of the magnitude of the hazard and the frequency was used to determine the
community vulnerability as HIGH, MODERATE or LOW. For example, a flood event is highly
_______________________________________________________________________
Page 14
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
likely (nearly 100% probability in the next year) in many communities but the degree of impact
varies. A highly likely flood with critical or catastrophic impact rates the community vulnerability as
HIGH. Another community with a highly likely or likely (at least one chance in the next 10 years)
flood with a limited impact would receive a vulnerability rating of MODERATE. The vulnerability of
a community having the occurrence of an event as possible or unlikely with limited or negligible
impact would be LOW .
Likelihood:
U = unlikely
P = possible
L = likely
HL = highly likely
Possible Hazard
High Wind /
Tornado /
Microburst
Likeli
hood
Impact:
N = negligible
L = limited
CR = critical
CA = catastrophic
Impact
Community
Vulnerability
Most vulnerable facilities and populations
Roads, Bridges, Culverts, Utilities, Residences,
Businesses, Ridgelines
HL
L
Low
HL
L
Moderate to
High
Structure Fire
L
N
Moderate
Wildfire
L
L
Moderate
Winter & Ice Storm
HL
L
Moderate
Hurricane
U
CR
Low
Earthquake
U
CR
Low
Drought
P
L
Moderate
Landslide
P
L
Low
Flood
Low lying hills, Culverts, Bridges, Residences,
Businesses, Roads
Residences, Businesses
Residents
Residences, Businesses
Town-wide
Town-wide
Residents, Farms, Businesses
Roads
Assessing Vulnerability: Addressing Repetitive Loss Properties
According the State Hazard Mitigation Officer, Londonderry has no repetitive loss properties. The
definition of severe repetitive loss as applied to this program was established in section 1361A of
the National Flood Insurance Act, as amended, 42 U.S.C. 4102a. An SRL property is defined as a
residential property that is covered under an NFIP flood insurance policy and:
(a) That has at least four NFIP claim payments (including building and contents) over $5,000
each, and the cumulative amount of such claims payments exceeds $20,000; or
(b) For which at least two separate claims payments (building payments only) have been
made with the cumulative amount of the building portion of such claims exceeding the market
value of the building.
For both (a) and (b) above, at least two of the referenced claims must have occurred within any
ten-year period, and must be greater than 10 days apart. http://www.fema.gov/severe-repetitiveloss-program
_______________________________________________________________________
Page 15
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
Assessing Vulnerability: Identifying Structures
Both the South Village and the North Village are in the floodplain. The shopping center at the
intersection of Rt. 100 and Rt. 11 is in the floodplain. In the North Village, the gas station and
restaurant are in the floodplain.







IGA – in the shopping center
Medical Clinic – not in the floodplain
Fire House – in the floodplain
Town Offices – In the S. Village, not in the
floodplain
Memorial Bridge of Londonderry
Goodevale Bridge connects Londonderry with
Jamaica
Boynton Road Bridge connects Londonderry with
Weston
is section could be much more robust with an Inventory of town assets –
# of houses
# of total structures
#of businesses
# of employees
Market value (total) of structures
Assessing Vulnerability: Analyzing Development Trends
The 2010 Census indicates a population of 1,769 and a growth rate of 3.5 percent over the 2000
population.
Town name
County
1990
Total
LONDONDERRY
Windham
1,506
2000
Total
90-00
Absolute
Change
90-00 %
Change
2010
Total
00-10
Absolute
Change
00-10 %
Change
1,709
203
13.5
1,769
60
3.5
One single family residential (SFR) permit has been issued in the last year. Subdivision permits
have been issued for future development, to be determined. A lot of secondary homes (vacation
homes) are presently for sale, therefore very little development is happening.
_______________________________________________________________________
Page 16
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
MITIGATION STRATEGY
Local Hazard Mitigation Goals
The Hazard Mitigation Goals as outlined below were developed by consensus among the
emergency management committee during meetings for the town of Londonderry local hazard
mitigation plan.
WE NEED SPECIFIC GOALS TO LONDONDERRY.
Develop Problem Statement from risk assessment data for each hazard profiled
Specify: what, where, how often, how bad
Example: High winds occur every year and cause damage to property in particular areas. Then
the Goal would be: protect existing buildings along particular corridor by ______________.
Mitigation Strategy, or action item would come from Goal – how do we address that particular
goal?
(Writing policy that will change zoning is one of the best mitigation strategies…)





Reduce the loss of life and injury resulting from all hazards.
Reduce the impact of hazards on the town’s water bodies, natural resources, and historic
resources.
Reduce the economic impacts from hazard events.
- Minimize disruption to the road network and maintain access,
- Mitigate financial losses incurred by municipal, residential, industrial, agricultural
and commercial establishments due to disasters,
- Ensure that community infrastructure is not significantly damaged by a hazard
event.
- Being proactive in implementing any needed mitigation projects for public
infrastructure such as roads, bridges, culverts, municipal buildings, etc.
Encourage hazard mitigation planning to be incorporated into other community planning
projects, such as the Town Plan, Capital Improvement Plan, and Town Basic Emergency
Operation Plan
Ensure that members of the general public continue to be part of the hazard mitigation
planning process.
Identification and Analysis of Mitigation Actions
The Londonderry Hazard Mitigation Committee identified the following new hazard mitigation
activities based on an evaluation of hazard event vulnerability. Are these current, done, deleted??
New buildings and infrastructure.
A new, permanent bridge is planned to be built in 2012. During TS Irene, Cobbleridge Road
bridge was taken out, but abutments stood. A temporary bridge is in place, but the town plans to
make an expanded, longer bridge as a permanent replacement.
Existing buildings and infrastructure.
As a result of TS Irene, four homes along the West River have substantial damage. Grant
applications are being written for the buy out of 2 homes and 2 businesses.
Identification and Analysis of Mitigation Actions: National Flood Insurance
Program (NFIP) Compliance
_______________________________________________________________________
Page 17
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
NFIP Description: The Town of Londonderry has Flood Hazard Area Regulations as a standalone ordinance and currently participates in the National Flood Insurance Program which was
updated in 2007. The updated FIRMs were made available to the town in the same year of 2007.
The town went through the process of holding a public hearing giving citizens the opportunity to
view the new maps. Additionally, Londonderry has no repetitive loss properties per FEMA’s
definition.
NFIP Action: The Town works with the elected officials, the state and FEMA to correct
compliance issues, of which there are none. The local zoning administrator administers the flood
regulations for the Town of Londonderry.
Implementation of Mitigation Actions
Mitigation actions are listed in priority order, with the most critical needs listed at the top of the list.
The following criteria were used in establishing project priorities. The ranking of these criteria is
largely based on the best available information and best judgment as many projects are not fully
scoped out at this time.












Does the action reduce damage?
Does the action contribute to community objectives?
Does the action meet existing regulations?
Does the action protect historic structures or structures critical to town operations?
Can the action be implemented quickly?
Is the action socially acceptable?
Is the action technically feasible?
Is the action administratively possible?
Is the action politically acceptable?
Is the action legal?
Does the action offer reasonable benefits compared to its cost of implementation?
Is the action environmentally sound?
Check these for current action items.
HAZARD
RESPONSIBLE
BEING
ACTION
PARTY
MITIGATED
Tree Inventory
High Winds
to determine
trees that will
Road Foreman
affect power
lines
High Winds
Checking
Culverts and
Road Foreman
under bridges
debris jams
Community
High Winds
Education and
Outreach
Program on
Town Selectmen,
how to
EMD
construct a
residential safe
room.
Codes and
Town Selectmen
TIMEFRAME
FUNDING
SOURCE
MITIGATION = M
PREPAREDNESS
=P
Project
Priority
Annually
Highway
Dept.
Budget
Maintenance
High
After every
significant wind
storm
Highway
Department
Budget
2 years
Emergency
Manageme
nt Budget
1 year
Town
Maintenance
High
Mitigation
Medium
Medium
_______________________________________________________________________
Page 18
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
High Winds
Flood
Flood
Standards –
mandatory use
of connectors
and brackets
with new
construction
Acquisition/Buy
outs of
properties
substantially
damaged along
the West River
Cobbleridge
Road Bridge
expansion
Flood
Winter/Ice
Storm
Winter
Storm / Ice
Storm
Winter
Storm / Ice
Storm
Winter
Storm / Ice
Storm
All Hazards
Goodevale
Road
embankment
stabilization
Checking
Culverts and
under bridges
for ice and
debris jams
Provide backup
power supply
for critical
facilities
Bury power /
utility lines into
town critical
facilities
(schools, town
office)
Establishment
of an
Emergency
Shelter at
Flood Brook
Elementary
School - with
generator
Training of
EMD for Level I
certification and
Town Officials
in ICS 100 &
402
Budget,
Emergency
Manageme
nt Budget
Mitigation
Mitigation
Town Selectmen
1 year
HMGP
Town Selectmen
/ Road Foreman
2 years
FEMA
Public
Assistance
Road Foreman
1 year
VTrans
grant/DOT
Road Foreman
Every winter
Highway
Department
Budget
Maintenance
High
Selectmen, EMD
1 year
Town
Emergency
Budget
Mitigation
High
Selectmen
3-4 years
Town
Budget
1 year
Red Cross
Generator
Grant
1 year
Volunteer
time /
Training
provided by
HSU
Selectmen / EMD
Selectmen
Mitigation
Mitigation
Mitigation
High
Medium
High
Medium
Preparedness
Medium
Ppreparedness
At the time of applying for FEMA’s PDM-C, FMA or HMGP grant programs, each project listed
below will undergo the full benefit-cost analysis methodology (BCA version 4.5 and higher) to
maximize savings.
_______________________________________________________________________
Page 19
High
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
Fluvial Erosion Hazard Zones (FEH)
Fluvial Erosion Mapping has not yet been done for the Town of Londonderry??. In
acknowledgement that existing technical resources and land use guidance or regulatory
authorities, such as the National Flood Insurance Program, do not adequately identify high risk
areas for development along riparian corridors with respect to fluvial erosion hazards it is
therefore deemed a high priority of this Hazard Mitigation Plan to provide the technical support
for, and to develop and implement protection mechanisms at the local level that will serve to
avoid land use investments that would be, over time, endangered by, incompatible or in conflict
with fluvial adjustment and erosion processes. Fluvial assessments shall be conducted as
guided by the VT ANR Fluvial Geomorphic Assessment Protocols, in the Town of Readsboro,
as VT ANR deems necessary.
No later than one year after completion of the fluvial geomorphic assessment, the town, under
contract with the Regional Planning Commission, or other GIS mapping service provider, shall
develop a fluvial erosion map. Such map shall be consistent with mapping standards and
protocols developed by VT ANR.
The Windham Regional Commission has recently been awarded grant funding for FY 2013-2014
under the Ecosystem Restoration Grant Program to conduct Phase 1 & Stream Geomorphic
Assessments on the Winhall River, Wardsboro Brook and the Green River, all within the
Windham Region. The Winhall River flows through a southern portion of the town where it joins
with the West River.
PLAN MAINTENANCE PROCESS
Monitoring, Evaluating, and Updating the Plan
The Town of Londonderry will continue to work with the Windham Regional Commission to
monitor, evaluate, and update the plan throughout the next 5 year cycle. A review of the plan will
take place each year by the emergency planner at the Windham Regional Commission along with
the Town’s emergency planning committee to update the plan after any FEMA disaster
declaration as well as any funding received from FEMA, to record any hazard related events, or
to determine if the town is interested in applying for grant funding. Additionally, the emergency
committee will assess ongoing hazard mitigation work and coordinate among stakeholders to
identify structures and engineering projects that can help mitigate future hazardous events; e.g.
bridge and culvert replacements, road replacements and grading, as well as any repetitive loss
structures that may be in the Special Flood Hazard Area as identified on FEMA Flood Maps (e.g.
FHBM and FIRM maps). Public input would also be included.
Additionally, all plan review meetings will be publicized land open to the public. The plan and any
proposed revisions will be on the jurisdictions website with information on how the public can
direct questions/comments to the planning team.
Incorporating into Existing Planning Mechanisms
The following policies, programs and activities related to hazard mitigation are currently in place
and/or being implemented in the town of Londonderry. The Committee analyzed these programs
for their effectiveness and noted improvements needed. Londonderry uses all of the plans listed
below to help plan for current and future activities with the town. For example: the Basic
Emergency Operation Plan has a contact list that is used for response purposes in the case of a
hazard event. The Town Plan directs visions and goals that include Natural Resources and LandUse. Road Standards are followed by the town and they do an annual culvert and bridge
inventory that is mapped by the WRC. The town is compliant with the NFIP.
_______________________________________________________________________
Page 20
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
Description
Effectiveness/Enforcement/
Hazard that is addressed
Gaps in Existing
Protection/Improvements
Needed/Other
Plan for coordinated
town-wide planning
for land use,
municipal facilities,
etc.
Flooding Addressed
Town Plan adopted in 2005,
Geography section of this
plan taken from Town Plan
Town Basic
Emergency
Operation Plan
Municipal procedures
for emergency
response
Incident Command; Hazard
Annexes included
School
Emergency
Response
Protocol
School procedures for
emergency response
School Crisis Plan
Type of Existing
Protection
Town Plan
LEPC 6
Hazardous
Materials Plan
Mutual Aid –
Emergency
Services
Mutual Aid –
Public Works
Road Standards
Sewage
Regulations
Flood Hazard
Area Regulations
Procedures for
hazmat and all
hazards emergency
response at regional
level
Agreement for
regional coordinated
emergency services
Agreement for
regional coordinated
emergency highway
maintenance services
Design and
construction
standards for roads
and drainage systems
Regulates on-site
sewage systems
Regulates
development in FEMA
flood hazard areas
LEPC 6 has the plan
BEOP to be completed in
2012 after Town Meeting
and adopted by Town Select
board
School Crisis Planning Team
Facilitator currently meeting
with schools and First
Responders to asses gaps
and offer solutions
Continued involvement with
the LEPC 6, including
training for EMD certification
and ICS training for Town
Officials underway.
Keene (NH) Mutual Aid –
written agreement/contract for
Fire/Ambulance and HazMat
None identified
Status Unknown
Status Unknown
Adopted VT State codes and
standards.
No major gaps identified
State Regulations apply
None Identified
Flood Hazard Overlay District
within Zoning Bylaw –
enforced by Zoning
Administrator
Revised in 2007 to include
new FEMA DFIRM’s.
National Flood
Insurance
Program (NFIP)
Site Plan Review
(SPR)
Provides ability for
residents to acquire
flood insurance
NFIP member
updated September 2007
None Identified
Site development
standards
Town Zoning Regulations
None Identified
Maintenance
Programs
Bridge & Culvert
Inventory
Updated in 2006
Completed Annually
None Identified
_______________________________________________________________________
Page 21
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
Building Code
Regulates building
construction
standards
Wetland
protection – VT
Wetland Rules
Protected by 1990
Vermont Wetland
Rules
Through Labor and Industry
Protection of environment,
water resources, wildlife,
biota
NA
None Identified
_______________________________________________________________________
Page 22
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
APPENDICES
A. Sign-in Sheet for Emergency Planning Committee Meeting
B. Public Participation Documentation
_______________________________________________________________________
Page 23
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
Appendix A: Sign-in Sheet(s) for Town of Londonderry Hazard Mitigation Plan
meeting.
Need current sign-in sheets.
_______________________________________________________________________
Page 24
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
_______________________________________________________________________
Page 25
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
_______________________________________________________________________
Page 26
Single Jurisdiction Hazard Mitigation Plan  Town of Londonderry, VT– 2/16/2016
Public Notice advertising availability of Londonderry Hazard Plan for review and
public comment.
Put current ad here.
_______________________________________________________________________
Page 27