2.2 Vulnerability. Strategy for Reducing Risks From Natural Hazards in Narragansett, Rhode Island. Clark, RI CRMC, Narrow River SAMP, 1999.

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1 2.2 Vulnerability After identifying types and areas of risk, a vulnerability analysis can help to determine the weak points in the community. This assessment examines the vulnerability of the built environment, such as structures, utilities, and roads and bridges, as well as environmental vulnerability, such as beaches that can suffer from erosion. A vulnerability analysis also estimates the number of people exposed to hazards, including elderly populations and concentrated populations such as children in schools or day care centers. According to Clark, vulnerable groups are those who are likely to suffer a disproportionate share of the effects of hazardous events. This designation is usually based on the group s coping ability (i.e., age, disabilities, income, and lifelines). 12 A vulnerability assessment includes such things as whether the shelter capacity is sufficient for the affected population, and whether businesses are likely to face temporary closure due to natural disasters. Historical damages are often good indicators for current exposure and potential damage. Economic and Social Vulnerability FEMA estimated that the value of property vulnerable to flooding and insured by NFIP in Narragansett is over $137 million (see Table 2). Since property taxes account for over 90 percent of the town s revenues, and 90 percent of the property tax is residential, it is wise for property owners to take precautions to protect their investments. The Risk Assessment Matrix (see Table 4) highlights high risk areas in Narragansett and Maps 1 and 2 show the location of most of these areas. The at risk population has increased over the years, with more development (both year-round and seasonal) occurring in vulnerable flood areas. The number of houses around Point Judith and Potter ponds has more than doubled since the last major hurricane in The Middlebridge and Bridgetown sections of the Narrow River estuary have been extensively damaged in the past and many more houses, especially year-round residences, have been constructed since the last major storm. Since the 1954 hurricane, residential development has also increased along Point Judith Pond and Bonnet Shores. The building code requires houses to be built for a minimum of 90 mph wind speeds. Schedule D Exposure Rating in the state building code has been in effect since 1997 and requires that structures located within 1,500 feet of a waterbody have special provisions for high wind areas. Therefore, only newer or recently renovated homes meet these design criteria. The building code is strictly enforced so lack of implementation does not pose a greater risk for structures built after Most of this residential development took place before building regulations required floodproofing construction in flood zones. Approximately 1,000 Narragansett property owners have flood insurance policies (see Table 2). Most of these are located in the following areas: Bonnet Shores, Great Island, Harbor Island, Mettatuxet Road (which lies between Route 1A and the Pettaquamscutt River in the northern section of town), Pettaquamscutt Lake Shores area, Succotash Road, Dunes Club (near town beach) and Boston Neck Road. Coastal storms pose a threat to several low-lying areas including Jerusalem, Galilee, Point Judith Pond, Sand Hill Cove, Narrow River and Narragansett Pier. The salt pond region is particularly at risk of flooding and erosion. Steady growth within the flood zone areas of the Narrow River has occurred over the past 45 years, with much development occurring before the adoption of the standard regulations for construction in the flood-prone areas. 13 The commercial buildings in the port of Galilee were all developed before the institution of the NFIP standards for construction, 14 so they do not meet current floodplain regulations. 12 Clark, RI CRMC, Narrow River SAMP, RI CRMC,

2 There are an estimated 1,031 insured structures mostly single-family units (see Table 2). Five of those properties the Coast Guard House Restaurant, and the Dunes Club, and properties located in Kenyon Estate (Percy Lane), Breakwater Village (Shore Road), and on Succotash Road have sustained 15 combined and repetitive flood loss. A repetitive loss is defined as a property that has sustained at least two losses due to flood damage, each greater than $1,000, since Table 2. National Flood Insurance Information for Narragansett Total Flood Value of Policies in Policies in Number of Claims Number of Insurance Property V Zones* A Zones* since 1978 Repetitive Loss Policies Covered 1,031 $137,805, (totaling $1,890,519) * (FEMA, April, 1999). Aerial view of Galilee Escape Road Photo courtesy: Office of Marine Programs Several critical facilities are located within vulnerable areas subject to both flood, storm surge and wind damage. Although the elderly housing is not located in the floodplain, it is near the hurricane evacuation area. This is of special concern because more lead time will be needed for hurricane evacuation and residents may have special needs during an evacuation. Two day care centers are located in the southern section of town near Narragansett Pier and the town beach (see Map 2). Neither day care center is located in the floodplain, although the Growing Child Day Care Center is located in a hurricane evacuation area and is of special concern because of the concentrated population in the building during the day. There are trailer parks and homes in this area that have suffered repetitive flood damage. Fortunately, there are no medical/institutional facilities located within the hurricane surge areas. However, a sewage treatment facility, which services the southern part of town and all of Galilee, is located within the flood zone just south of Scarborough Beach. Evacuation Between 1950 and 1990, the population of the town grew nearly 550 percent, which makes Narragansett the most densely developed municipality in Washington County, with 1,500 residents per square mile and an average year-round population of about 20,000 people. About 40 percent of Narragansett s permanent residents would have to evacuate for a weak hurricane, and almost 60 percent for a strong hurricane. During hurricane season, the addition of summer residents and tourists doubles the population, increasing its vulnerability. Tourists are even more vulnerable, 14

3 because they are unfamiliar with town emergency procedures. 15 Areas that need to be evacuated in the event of a major hurricane include Galilee, Great Island, Harbor Island and the community of Jerusalem, because they have single points of egress that have been flooded and bridges that have been washed out in prior hurricanes. The bridges to Jerusalem and Great Island, along with roads through Matunuck and Galilee, are located within the 100-year flood zone surrounding Point Judith and Potter ponds. Map 2 (northern and southern sections) depicts critical facilities, area flood zones and evacuation routes. Extensive sections of several roads are subject to flooding and storm surge. After the 1954 hurricane, the Galilee Escape Road was elevated to 12 feet above mean sea level, but sections of the road are still vulnerable to flooding, especially as sea level rises (Rubinoff 1990). The Bonnet Shores causeway and Col. John Gardiner Road are also susceptible to flooding and could pose an evacuation problem. Great Island, Jerusalem, Middlebridge and houses along Pettaquamscutt River are also susceptible to road flooding and bridge wash-out. The Succotash Road Bridge collapsed into the channel bed during Hurricane Carol and a skiff ferry had to rescue marooned people on the Jerusalem side. The causeway leading to Harbor Island is at risk of flooding, which could impede evacuation for the several hundred houses on that island. Shelters Shelter use in terms of evacuation is not easily predicted because each emergency situation presents a new set of circumstances. Variables include the length of the warning period, official encouragement of the evacuation, public awareness of location and availability of shelters, level of income of the area, and the severity of the approaching hazard. Local officials do have some degree of control over the population that seeks public shelters. If evacuees are encouraged to seek safely at the homes of friends or family, hotels/motels, or shelters that are not advertised, usage will be lower than if shelters are opened early and widely advertised. Evacuations that occur late at night tend to put added stress on shelters because of the increased sense of urgency and inability to contact family and friends in order to make alternative arrangements. A smaller period of time between the evacuation notice and the landfall of the storm usually causes greater use of the shelters because of the rapid nature of the evacuation. The number of retirement communities and trailer/mobile home parks in an area affects shelter use because both of these communities are more likely to seek public shelter. Narragansett has two trailer/mobile home parks, both of which are located near possible hurricane evacuation zones. All of the people residing in the trailers are assumed to need shelter. It is generally recommended that residents of mobile homes seek shelter in a significant storm event. Hurricane evacuation notices should be released eight hours before the predicted landfall of the storm. This gives most residents plenty of time to seek alternatives to riding out the storm in public shelters, minimizing the shelter demand and opening spaces for those really in need. Table 1 lists both shelter demand and availability. During a weak hurricane it is projected that Narragansett will be short 575 spaces in American Red Cross-designated shelters. A severe hurricane would require shelter space for an additional 895 people. These numbers do allow for some fluctuation in projected shelter needs. 15 Clarkson Collins, AICP, pers. comm. 15

4 Table 3. Estimated Public Shelter Demand/Capacity for South Kingstown, RI 16 Strength of Surge Vulnerable Non-Surge Mobile Home Total Shelter Total ARC Storm Residents Vulnerable Residents Residents Demand Shelter Capacity 17 Weak Severe The town s only American Red Cross approved shelter, Pier School, can only accommodate 135 evacuees (location is shown on Map 2). According to the U.S. Army Corps of Engineers, the Pier School is located near an area of poor drainage and may be susceptible to minor flooding during severe rainfall events. The American Red Cross is concerned about the location of this shelter because it is located near a river and just outside the predicted hurricane inundation area (see Map 2), which could separate the northern section from the southern section of town. There are other possible shelter locations that are not American Red Cross-approved. One is the Christian Brothers building on Ocean Road (capacity about 30). The town is now working with the American Red Cross to establish the University of in Kingston as a shelter for Narragansett. Public Infrastructure and Emergency Life Lines There is substantial state and federal investment in beach, port and harbor facilities that are located in vulnerable areas. The Roger Wheeler State Beach pavilion is a fairly new structure located in the V zone. Although the beach pavilion is fairly well protected by the Harbor of Refuge breakwaters, it was still required to conform with NFIP standards. It has been built high enough to survive a 100-year flood. The fire/police station, located at 40 Caswell Street (north of South Pier Road), is located in the floodplain, but has been elevated above the 100-year flood level. Although the structure itself is elevated, access roads for the fire/police station may flood during a storm. Middlebridge and Narrow River have recently been hooked up to town sewers, so these two vulnerable low-lying areas will not be subject to a health risk from sewage overflow. However, contamination from flooded individual septic discharge systems (ISDSs) can be expected in future storms. 18 Several storm water outfalls discharge into Point Judith Pond at Galilee... Backwater flooding may occur within the low-lying roadways in the adjacent high-density neighborhoods of Sand Hill Cove during heavy storm events (Rubinoff 1990). Ocean Road is a popular spot for both onlookers and the media during storms. There are considerable public health and safety concerns associated with Ocean Road during nor easters and hurricanes. The seawall along Ocean Road was destroyed in the hurricane of 1938 and is not routinely inspected. Today, large sewer and water lines, which are maintained by the town and the United Water Company of, run beneath Ocean Road. Map 2 shows the high risk bridges that have utilities underneath their structures and that were flooded or washed out in prior hurricanes. 16 US Army Corps of Engineers Hurricane Evacuation Study Original US Army Corps of Engineers Study uses a different shelter analysis than the one used here, in this case the most up-to-date ARC shelter data available was used. 18 RI CRMC,

5 The Middlebridge Bridge, which has been flooded in the past, now carries an important water line that services part of the north end of Narragansett and sewer lines that serve the houses along the west side of the Narrow River in South Kingstown. The residents of Narragansett and all the commercial enterprises in the area are vulnerable to destruction of this bridge and the water main that lies underneath. Breaks in the sewer line would not only leave the hundreds of residents along the river without sewage disposal, but would also result in raw sewage discharge into the Narrow River. The Lacy Bridge (Bridgetown Road) is also susceptible to flooding. There are water lines and gas supply lines underneath this bridge that serve residential areas along the Narrow River and northern Narragansett. The bridge to Great Island has water lines suspended underneath it. Two fire hydrants have recently been installed on either side of this bridge. This safety measure will help provide drinking water if the bridge is destroyed again as it was in 1954 s Hurricane Carol. The main line of the South Kingstown South Shore Water System, which supplies water to Jerusalem, travels north to Snug Harbor across the Succotash Road Bridge. The bridge washed out in both the 1938 and 1954 hurricanes. In the 1938, 1944 and 1954 hurricanes, a storm-surge channel was re-established across Sand Hill Cove Beach. In each of these hurricanes, a storm surge channel into Potter Pond was also re-activated across East Matunuck Beach. Today such a channel could cause a break in the watermain that serves Jerusalem. Environmental Vulnerability (beach erosion) The south shore barrier beaches are sediment-starved and have an exceptionally narrow and low profile, which leaves them susceptible to storm-surge and overwash processes. 19 The town s beaches were severely damaged by both the 1938 and 1954 hurricanes and in many instances have been heavily redeveloped despite similar risks today. A hurricane would wash debris from these coastal structures A bicyclist braves the stormravaged asphalt parking lot at Narragansett Town Beach after Hurricane Bob. Photo courtesy: Providence Journal Company 19 RI CRMC, Salt Pond Region SAMP,

6 into the Galilee marsh, a major federal/state restoration site. Where seawalls have been constructed to protect property on the upland edge, there is no place for the beach to retreat and intertidal beach habitat will eventually be lost altogether. 2.3 The Process of Developing This Hazard Mitigation Plan Local government officials in Narragansett assessed the risks to the town and developed mitigation actions that address a mix of structural and non-structural initiatives to minimize the vulnerability of the town to effects of future hazards. Those actions are detailed in Section 3.0. Narragansett also developed a Risk Assessment Matrix (see Table 4) that summarizes the priority areas at risk from flooding and other hazards. 2.4 Maps The University of Environmental Data Center created two Geographic Information System (GIS) maps for Narragansett one for areas that were listed on the Risk Assessment Matrix (see Table 4), and the other for critical facilities in the town (see Maps 1 and 2). Map 1 shows two categories of barrier beaches that the Coastal Resources Management Council (RI CRMC) has categorized as moderately developed and developed. Moderately developed barrier beaches are essentially free of houses, commercial/industrial buildings and/or facilities (excluding utility lines), while developed barriers may also contain surfaced roads and structural shoreline protection facilities (RI CRMC 1998). The green circles on Map 2 are traffic control points where police will be located to help expedite evacuation procedures. Map 3 displays the locations of flood zone boundaries projected for parts of Narragansett in the year Recently, FEMA redesignated the B flood zone the X zone (500-year). A conservative sea level rise estimate of 125 cm above the National Geodetic vertical datum (NGVD) was used to model the location of flood zones in Capability Assessment The capability assessment examines the existing plans, programs and policies that that the town already has in place that incorporate hazard mitigation or other protective measures. Narragansett has initiated many studies and activities over the years that have laid the foundation for the development of this mitigation strategy. As a result of the hurricanes of 1938 and 1954, the escape route out of the Galilee/Jerusalem area was elevated above the 100-year flood level. In addition, a variety of hazard mitigation strategies were developed following the federal disaster declaration for Hurricane Bob in 1991 (these were mostly geared toward the Public Works Department for debris removal and clearing of roads for evacuation). The town implements and enforces the state building code and participates in the community rating system (CRS). Narragansett is rated a class of nine on a scale of 10 to 1 (with one being the best), which allows flood insurance policyholders a 5 percent discount on their premiums. Since the 1980s, Narragansett has actively worked on natural resource management issues, highlighted by RI CRMC s Salt Ponds Special Area Management Plan and the Narrow River Special Area Management Plan, and has incorporated various recommendations into town ordinances and public education campaigns. In addition, private and municipal land trusts have recently been active in protecting valuable natural open space (which can help minimize flood damage). Other efforts include a study Narragansett did with the U.S. Army Corps of Engineers on coastal flooding. The study s findings and recommendations can aid natural disaster planning, 18

7 response and recovery. The Narragansett Harbor Management Commission s Harbor Management Plan (Section Storm Management) identifies the need for pre-storm preparations such as storm safety education and hurricane preparedness plans for recreational boaters and commercial users of the harbor (such as the fishing fleet, Block Island Ferry, sightseeing boats and charter boat fleets). The town has a special flood hazard area overlay district where mobile homes and any other high risk structures are prohibited. The fire chief and the building inspector both have public education programs. As part of these programs, FEMA brochures are mailed to local residents and placed in public buildings and selected stores at least twice a year. The fire chief has worked with local real estate agents on fire issues to develop pamphlets with emergency numbers and evacuation tips. The fire chief also produces a quarterly one-page newsletter, which is also placed in public buildings and privately-owned stores. Some of these brochures are included in the local housing authority s newsletter. 2.6 Amending Comprehensive Plan Policies and Goals The LHMC has drafted mitigation actions to address the town s risks and vulnerabilities (Section 3.0) and has recommended that they be implemented into the Town Facilities and Services element of the comprehensive plan (see Appendix A). The comprehensive plan outlines goals, policies, issues and actions to provide a framework for everyday operations within the town. Narragansett recognized that inclusion of mitigation initiatives both pre-disaster and post-disaster would not only benefit the community by reducing human suffering, damages and the costs of recovery, but would also help build and maintain the sustainability and economic health of the community over time. These proposed amendments recognize the impact of natural hazard events and provide guidance on what various departments can do to protect life, property, natural resources and the economic health of the town. 2.7 Coordination with Neighboring Municipalities While drafting this strategy, Narragansett worked closely with the town of South Kingstown (particularly on the recommended hazard mitigation actions), because both towns share common concerns, such as evacuating residents and restoring and repairing the bridges that connect the towns. During a regional CRS meeting, both towns agreed to work together to produce an educational video on flood hazards that could be aired on a local cable station. A mutual aid agreement is being created that would allow both towns to use a tub grinder to help with debris removal following a storm event. 19