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Mitigating Flooding in Gays Mills, Wisconsin
Quantifying Success
Village History
The Village of Gays Mills is nestled in the Kickapoo River Valley, in Crawford County in the Driftless Region of southwestern Wisconsin. The village was named after civil engineer James B. Gay, who settled there in 1847 and built a dam, sawmill, and flour mill.
Villagers soon discovered that the area's soil conditions were ideal for growing apples. Apple orchards have since become central to the village's industry. Over a thousand acres of orchards surround the area and the annual Apple Festival draws tourists from across Wisconsin.
Although located in one of the most scenic areas in the state, the village’s flood-prone geography has proven challenging for many of its homes and businesses. The Kickapoo River, a tributary of the Wisconsin River, is named for an Algonquian word meaning "one who goes here, then there," a fitting description of its meandering path. Gays Mills’ location in the Kickapoo River watershed and low elevation have led to major flood events in the community, which have devastated livelihoods and caused expensive property damage.
This map shows Gays Mills' position adjacent to the Kickapoo River in the southern third of the Kickapoo River watershed. Large precipitation events can cause flooding when the volume of water exceeds the river’s capacity. Flooding is intensified in this area due to the river's creation of steep ridges and low valleys within the unglaciated terrain.
A History of Flooding in Gays Mills
Gays Mills has experienced 34 "action stage" flood events (river crests over 11 feet) since 1950.
Six of these were "major flood stage" events (crests over 17 feet).
Five of these six "major flood stage" events occurred during or after 2007.
A History of Mitigation Efforts
Throughout the history of Gays Mills, the community has made efforts to mitigate flooding and its effects on residents and businesses.
The US Army Corps of Engineers conducted studies and surveys in the area during the late 1930s and early 1940s. In 1962, a dam project was nearly completed before environmental and cost issues prevented its construction from continuing. Several additional levee projects were proposed during the 1970s, but ultimately were never carried out.
Due to hazard mitigation efforts over the past 20 years, however, many future losses from flooding will be avoided. Beginning in 2001, through a series of grants, Wisconsin Emergency Management (WEM) helped the Village to acquire properties that had sustained flood damage in the past. The structures were then demolished and the land was deed-restricted to open space in perpetuity.
Acquisition/demolition solutions are often used in hazard mitigation for properties located in a floodplain when those properties repeatedly sustain damages. These projects are more cost-effective in the long run than simply repairing damage to structures that are likely to flood again. Acquisition projects offer a more permanent solution than elevation projects, in which structures are raised above a potential future flood level. Both of these project types require voluntary participation from property owners.
Although FEMA initially approved the elevation of 17 properties in a 2007 grant, after further flooding occurred, some homeowners elected to have their properties bought out instead. In total, the Village acquired and demolished structures on 35 properties in Gays Mills.
The first acquisition/demolition project in Gays Mills began in 2001 after two flood events. The flooding significantly impacted the Crawford County Highway Shop, which provided emergency services during flooding including closing roads and performing rescues. Damage to the shop prevented employees from effectively carrying out these responsibilities because employees spent additional hours protecting their own equipment from devastation.
With a grant from Wisconsin Emergency Management through FEMA’s Hazard Mitigation Grant Program, the County was able to relocate the shop to an area of high elevation. The project was completed in 2003 and when major flooding occurred again several years later, the new building remained safely out of reach of high water.
Crawford County's new Highway Shop, now located outside of the floodplain in Seneca, WI
Two more major flood events led to the implementation of large-scale mitigation projects and flood recovery efforts.
In August 2007, the Kickapoo River crested at nearly its highest point ever recorded: 19.79 feet. Only one recorded flood had been higher: a 1978 flood with a 19.80-foot crest.
Downstream view of flooding in Gays Mills, August 23, 2007 (left image) and October 21, 2014 (right image)
Upstream view of flooding in Gays Mills, August 23, 2007 (left image) and October 21, 2014 (right image)
Then, in June of 2008, Gays Mills recorded the highest ever flood event of its history, with a crest of 20.44 feet. 90% of the village was affected, and the event received a Federal Disaster Declaration.
These floods, only 10 months apart, prompted discussion over relocating the village and led to visits from FEMA and WEM involvement. The Village created the Flood Recovery Committee in 2007, which worked with a consultant to develop grant applications for acquisition/demolition and elevation projects. Following the 2008 event, FEMA activated the Long-Term Community Recovery (LTCR) program under Emergency Support Function #14. This program was designed to help coordinate state and federal recovery assistance and support community response and discussion. Using the LTCR program, the Village completed a plan by October 2008 which served as a basis for both short-term and long-term recovery planning.
Villagers faced difficult options. They could choose to relocate their entire village as the neighboring town of Soldier's Grove had done, or they could partially relocate.
Opinions on the decision were divided. Because the relocation process was voluntary, partial relocation proved most feasible. The Village purchased land out of the Kickapoo floodplain to construct new homes and relocate local businesses. New structures included the Mercantile Center and Community Hall.
Gays Mills Loss Avoidance Study
A good indication of the effectiveness of a mitigation project is the return on investment (ROI). When flood events occur after a property has been acquired, the monetary losses from the event can be calculated using floodplain and river crest data, as well as information like residential displacement costs. The total losses avoided from the event, divided by the project's cost, give the return on investment. A return on investment of over 100% means that the project was cost-effective.
Data analyzed in a Loss Avoidance Study (LAS) from the six major flood events surrounding these mitigation projects (from 2007-2018) totaled an estimated 533% return on investment during this time period. This amount will continue to grow as additional flood events occur.
Interestingly, commercial properties showed a significantly higher return on investment than residential properties.
Structures with only one story also show higher returns on investment than structures with two or more stories. In addition, structures with a lower first floor elevation had greater returns on investment, perhaps because more elevated structures are less likely to be impacted by flooding.
Disaster Declarations
Acquisition/demolition projects are funded by grants through programs like the Hazard Mitigation Grant Program. To qualify for one of these grants, a community must apply for federal assistance after a disaster is declared. Major disasters are declared by the President when it is determined that damage exceeds the capacity of both local and state government resources. Disaster declarations are numbered and have the prefix "DR-."
Five separate disaster declarations, along with several other funding sources, allowed WEM to buy out the 35 properties in Gays Mills.
The following maps show properties acquired in Gays Mills during each disaster declaration for which the community received grant funding for buyouts.
- Note: dollar values in the following slides are adjusted for inflation to 2018 values.
DR-1369
Declared May 11, 2001, this disaster declaration was a response to spring flooding after severe storms. The Crawford County Highway Shop was relocated following this disaster.
1 commercial property
Cost of Property Acquisitions: $755,975.5
Total Losses Avoided: $9,437,924.30
Total Return on Investment (ROI): 1248.44%
DR-1719
Declared August 26, 2007. Tornadoes, storms and flooding over a two-week period in August led many Wisconsin communities to seek federal assistance.
18 residential properties, 1 commercial property
Cost of Property Acquisitions: $1,265,378.77
Total Losses Avoided: $4,193,555.05
Total Return on Investment (ROI): 331.41%
DR-1768
Declared June 14, 2008, after heavy rains, storms, tornadoes and flooding impacted 1,081 Wisconsin residences. 27 homes were destroyed in the disaster.
8 residential properties, 3 commercial properties
Cost of Property Acquisitions: $1,067,908.24
Total Losses Avoided: $1,702,483.43
Total Return on Investment (ROI): 159.42%
DR-4076
Declared August 2, 2012, after flash flooding caused significant property damage and resulted in three lives lost in nearby Clark County.
1 residential property
Cost of Property Acquisitions: $48,459.03
Total Losses Avoided: $158,511.02
Total Return on Investment (ROI): 327.1%
DR-4141
Declared August 8, 2013, after severe storms over a period of eight days resulted in historic rainfall in 11 Wisconsin counties.
1 commercial property
Cost of Property Acquisitions: $87,557.77
Total Losses Avoided: $1,719,707.16
Total Return on Investment (ROI): 1964.08%
Floodplain Maps
Flood events that occurred after the completion of these acquisition projects indicate the positive impact the projects have had on the Gays Mills community, and the losses avoided. Since the impactful events of 2007 and 2008, more significant flooding has occurred, including the highest crest yet at 22.31 feet (2018) and crests of 15.43 feet (2010), 18.10 feet (2016), and 18.08 feet (2017).
FEMA's National Flood Hazard Layer or Flood Insurance Rate Map (FIRM) designates the flood hazard zones of a community. At the right, the Kickapoo River is surrounded by the floodway in red stripes and the 1%-annual-chance floodplain in light blue.
The losses avoided due to the Gays Mills acquisitions were calculated by modeling the estimated area that flooded based on the crest height of each flood event. The dark blue outlines on the map show the modeled area flooded that will be seen in the following maps. Structure damages were then estimated based on the area and depth of each flood.
2007 modeled flooding, flood crest height: 19.79 feet
Only the Crawford County Highway Shop had been acquired.
2008 modeled flooding, flood crest height: 20.44 feet
6 additional properties had been acquired and demolished.
2010 modeled flooding, flood crest height: 15.43 feet
25 more buyouts had occurred, for a total of 32 acquisition/demolitions completed.
2016 modeled flooding, flood crest height: 18.10 feet
All 35 properties had been bought out.
2017 modeled flooding, flood crest height: 18.08 feet
2018 modeled flooding, flood crest height: 22.31 feet
Future Mitigation Efforts
Future flooding in Gays Mills is inevitable due to the steep valleys of the Kickapoo River's path. After a disaster was declared in the wake of the August 2018 flood event, the Village received grants for several additional acquisitions. Similar projects will continue in Gays Mills as more flooding occurs, to ensure the safety of lives and property.
The mitigation efforts in Gays Mills have proven enormously beneficial to the community by preventing millions of dollars in losses. Studies of the acquisition projects in Gays Mills show that certain structure attributes – number of stories and first floor elevation in particular – can affect the return on investment. This information could be used to help determine optimal future projects in Gays Mills, and perhaps in other areas of Wisconsin.
Glossary
Acronyms
- FEMA: Federal Emergency Management Agency
- LAS: Loss Avoidance Study
- WEM: Wisconsin Emergency Management
Terms
- 1%-annual-chance flood zone: Also called the base flood zone or 100-year flood zone. The flood level in this zone has a 1% chance of reaching or exceeding this height each year.
- Acquisition/demolition: A process of voluntary acquisition of properties located in a floodplain. Structures on the property are demolished. Future uses of the property are then deed-restricted to ensure open space remains. For example, the land could be used for a greenspace or park.
- Action stage: The flood stage which, when reached by a rising stream, represents the level where the National Weather Service or a partner/user needs to take some type of mitigation action in preparation for possible significant hydrologic activity.
- Disaster Declaration: Disasters are declared by the US President when communities and states are unable to supply the funding necessary to recover from the event. Declaration requests are made by the Governor. The declaration process is a part of the Stafford Act.
- Elevation: A process of raising or elevating structures in a floodplain above the base flood elevation, or the 1%-annual-chance flood level, to mitigate future damages.
- Emergency Support Functions (ESFs): Groupings that create an organizational structure to coordinate support among federal agencies in response to emergencies.
- Flood crest: The highest stage or level of a flood wave as it passes a point.
- Floodway: A channel designated for base flooding that must remain cleared in order to prevent increases in water surface levels.
- Hazard Mitigation Grant Program (HMGP): A grant funded by FEMA which local, state, and tribal governments and certain private non-profits are eligible to apply for after a Federal Disaster Declaration, in order to mitigate future losses from a similar disaster.
- Long-Term Community Recovery (LTCR): A program designed to help coordinate state and federal recovery assistance for communities and to provide planning, technical, and other support to communities.
- Return on investment: The monetary returns from a project, calculated by dividing total losses avoided by total cost.