Town of agawam hazard mitigation plan
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- River Road
- Upper Suffield Street (Route 75)
- North Street
FloodsHazard DescriptionThere are three major types of storms that can generate flooding in Agawam:
A floodplain is the relatively flat, lowland area adjacent to a river, lake or stream. Floodplains serve an important function, acting like large “sponges” to absorb and slowly release floodwaters back to surface waters and groundwater. Over time, sediments that are deposited in floodplains develop into fertile, productive farmland like that found in the Connecticut River valley. In the past, floodplain areas were also often seen as prime locations for development. Industries were located on the banks of rivers for access to hydropower. Residential and commercial development occurred in floodplains because of their scenic qualities and proximity to the water. Although periodic flooding of a floodplain area is a natural occurrence, past and current development and alteration of these areas will result in flooding that is a costly and frequent hazard. LocationThere are approximately 1022 acres of land within the FEMA mapped 100-year floodplain and 262 acres of land within the 500-year floodplain within the Town of Agawam. Most of this area is located adjacent to the Connecticut River. This includes Bondi's Island where the Springfield Water and Sewer Commission operates its wastewater treatment plan and to which numerous sewer pipes flow. Based on these locations, flooding has a “medium” location of occurrence, with 10 to 50 percent of land affected. The following specific locations are prone to flooding: River RoadThe River Road neighborhood is located in the floodplain. It consists of 37 streets and approximately 370 residential homes northwest of River Road. Lower Suffield Street (Route 75)Localized flooding has occurred in the past on lower Suffield Street at the crossing with Westfield Brook. Flooding has occurred in this area in recent years due to inadequate culvert capacity. Approximately 3 residential structures could be affected by localized flooding. There is potential for damage to Route 75. Upper Suffield Street (Route 75)Portions of upper Suffield Street have experienced localized flooding in the past. Flooding has occurred in this area in recent years due to inadequate culvert capacity and is exacerbated by beaver dams. There are no structures in the area where the flooding occurs, though there is potential for damage to Route 75. North StreetThe road has experienced minor flooding, due to culvert problems over White Brook. There is no record of major flooding in this area. Approximately 4 residential structures and a sewer pump station could be affected by flooding at this location. Leonard PondA 75-year storm in the 1980s caused significant damage to residential homes along Kathy Terrace. Approximately 15 residential structures could be affected by a flood incident at this location. Beaver issues contribute to flooding in this location. Extent Floods can be classified as one of two types: flash floods and general floods.
The average annual precipitation for Agawam and surrounding areas in western Massachusetts is 46 inches. Previous Occurrences Historically, the majority of flooding in Agawam has been localized, affecting particular neighborhoods or areas containing small ponds or wetlands that overflow when the town receives heavy rainfall. The locations in the previous section (lower and upper Suffield Street, North Street, and Leonard Pond) are places in Agawam at which flooding has occurred. Suffield Street experiences annual flooding due to inadequate culvert capacity and beaver dams, while North Street receives minor flooding on an annual basis and Leonard Pond flooded due to a storm in 1983. The one major flood event on record occurred in March of 1936, when an unusually cold and snowy winter, followed by a spell of warm and rainy weather, turned the normal spring rising of the Connecticut River into an unprecedented natural catastrophe. The flood inundated Agawam, as well as Hadley, Hatfield, Northampton, and Springfield. In Massachusetts, the flood resulted in 10 deaths and left 50,000 people homeless. Estimated damage statewide was $200 million in 1936 dollars, or $3.4 billion in 2014 dollars. Flooding during Tropical Storm Irene in 2011 caused sheet piling in a 250' section of levy along the Westfield River to erode and fold. The Army Corps of Engineers has since worked with Agawam to reinforce the levy in this location, but there are already signs of slope failure. This is especially concerning because a sewer line runs within this section of slope. Relocation of the sewer line away from the river is a high priority. The DPW has allocated funding in the coming fiscal year budget to pursue design work toward this end, but will need funding for implementation. The Town of Agawam has a gauge on the Connecticut River to indicate height of river at the Campbell Road pump stations. The National Weather Service monitors flooding crests for the Connecticut River, at the nearest National Weather Service station located directly upstream from Agawam in Springfield, Massachusetts. There is also a station located in Westfield, Massachusetts to monitor the Westfield river. The NWS has various flooding classifications based on water level. These classifications and their definitions are: Action Stage - the stage which, when reached by a rising stream, represents the level where the NWS or a partner/user needs to take some type of mitigation action in preparation for possible significant hydrologic activity. The type of action taken varies for each gage location. Gage data should be closely monitored by any affected people if the stage is above action stage. Minor Flooding is defined to have minimal or no property damage, but possibly some public threat. A Flood Advisory product is issued to advise the public of flood events that are expected not to exceed the minor flood category. Examples of conditions that would be considered minor flooding include:
Moderate Flooding is defined to have some inundation of structures and roads near the stream. Some evacuations of people and/or transfer of property to higher elevations may be necessary. A Flood Warning is issued if moderate flooding is expected during the event. Examples of conditions that would be considered moderate flooding include:
Major Flooding is defined to have extensive inundation of structures and roads. Significant evacuations of people and/or transfer of property to higher elevations are necessary. A Flood Warning is issued if major flooding is expected during the event. Examples of conditions that would be considered major flooding include:
The flood categories for the Connecticut River at the Springfield station are:
The previous occurrences of these flooding categories being reached by the Connecticut River in Springfield are as follows:
Source: National Weather Service, http://water.weather.gov/ahps2/hydrograph.php?wfo=box&gage=spgm3 The flood categories for the Westfield River at the Westfield station are:
The previous occurrences of these flooding categories being reached by the Westfield River in Westfield, Massachusetts are as follows:
Source: National Weather Service, http://water.weather.gov/ahps2/hydrograph.php?wfo=box&gage=wsfm3 Probability of Future Events Based upon previous data, there is a moderate probability (10 to 40 percent in any given year) of flash flooding or general flooding occurring in Agawam. Flooding frequencies for the various floodplains in Agawam are defined by FEMA as the following:
Climate scientists predict that in the next few decades, climate change will increase the frequency and intensity of all storms that can cause flooding. Currently, floods are the most costly natural hazard in the United States, and climate change will only increase this damage. More information about the effect of Climate Change can be found in the Pioneer Valley Planning Commission’s Climate Action Plan, available at www.sustainableknowledgecorridor.org. The Massachusetts State Climate Change Adaptation Report has additional information about the impact of climate change and can be accessed at www.mass.gov/eea/air-water-climate-change/climate-change/climate-change-adaptation-report.html. Impact The town faces a “critical" impact, with 25 percent of property in the affected area damaged or destroyed, from flooding. Based on the town's median home value of $230,500 and an estimated 25 percent of damage to 100 percent of affected structures, the following are the estimated impacts from flooding:
The cost of repairing or replacing the roads, bridges, utilities, and contents of structures is not included in this estimate. Vulnerability Based on the above analysis, Agawam has a hazard index rating of "2 - High Risk" for flooding. Directory: filestorage filestorage -> M. E. M. A. (Managed Emergency Mass Allocation) filestorage -> Carver Pool and Spray Park (1023 S. McKinley- albany, ga) Summer 2014 filestorage -> 20 Chapter Programming 3d graphics with OpenGL filestorage -> - filestorage -> 24 Chapter Exploring Text to Speech filestorage -> Subject: City Manager’s Report Download 0.54 Mb. Share with your friends:
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