Browsing by Subject "Floods"

Now showing 1 - 7 of 7
  • Thumbnail Image
    Item
    2012 Northeast and Central Minnesota Flooding
    (2015) Curtice, Brian
    This three-page pdf is a FEMA proclamation issued on July 6 2012 concerning the June 14-21 2012 floods in the Duluth area. All of Minnesota's coastal counties and communities were included in the declaration, along with the Fond du Lac, Mille Lacs and Grand Portage bands of Ojibwe. The declaration includes public assistance and disaster mitigation in the affected areas totaling $44.7 million. Also noted is emergency legislation totaling $167 million passed by a special session of the Minnesota Legislature and signed by Governor Mark Dayton.
  • Thumbnail Image
    Item
    Climate Change Adaptation of Urban Stormwater Infrastructure
    (Minnesota Department of Transportation, 2023-06) Erickson, Andrew J.; Herb, William R.; Gallagher, Noah D.; Weiss, Peter T.; Wilson, Bruce N.; Gulliver, John S.
    The final analysis of historical (TP-40), current (Atlas 14), and future predicted storm events for three watersheds in Minnesota (Duluth, Minneapolis, Rochester) has shown that current design philosophy is not sufficient to prevent flooding from 10-year and larger design storm events and that flood depth and duration will increase given current climate projections. Several stormwater infrastructure adaptation strategies were assessed for reducing flood depth and duration: Baseline (existing conditions), adding rain gardens (aka, Infiltration Basins), adding new wet ponds, retrofitting existing stormwater ponds to be ?Smart Ponds, adding new Smart Ponds while also converting existing ponds into Smart Ponds, or upsizing of stormwater pipes to convey more water. In watersheds that are mixed urban, suburban, and rural like Rochester?s Kings Run or Duluth?s Miller Creek sub-watersheds, the most cost-effective climate change adaptation strategy was to build new stormwater wet ponds (Extra Ponds strategy) to treat the impervious surfaces not currently treated by existing wet ponds and other stormwater BMPs. In the fully developed urban 1NE watershed in Minneapolis, the most cost-effective (excluding land costs) climate change adaptation strategy was building wet ponds (Extra Ponds). Securing property for building new stormwater infrastructure in fully developed urban watersheds like 1NE may be a substantial cost compared to other watersheds. Smart Ponds do not require additional land for implementation and thus represent a relatively low-cost alternative that will be more beneficial in watersheds with numerous existing wet ponds.
  • Thumbnail Image
    Item
    Encroaching Tides: How Sea Level Rise and Tidal Flooding Threaten U.S. East and Gulf Coast Communities over the Next 30 Years
    (2014) Spanger-Siegfried, Erika; Fitzpatrick, Melanie; Dahl, Kristina
    This recent study examined coastal flooding along the Eastern and Gulf coasts of the US, and did not include the Great Lakes. However, the report concludes that extreme weather events and floods are occurring nationwide, and that other coastal communities are also at higher risk. Coastal communities and states, and the nation as a whole, need to prepare for near-term changes in tidal flooding, while working hard to minimize longer-term losses through efforts to both adapt to these changes and limit their extent. The report outlines steps to ensure more resilient coastal communities, which are extracted and reproduced below. “BUILDING COASTAL RESILIENCE IS A LOCAL IMPERATIVE . . . Over the next few decades—the time frame of our analysis—changes set in motion by our past and present heat-trapping emissions will largely drive the pace of sea level rise. The lag of several decades between the release of carbon into the atmosphere and the response of the ocean means that more tidal flooding is virtually guaranteed, and that communities need to act with urgency. Locally, there are many things we can do to help ensure enduring coastal communities, including: • Upgrade the built infrastructure in harm’s way. With help, communities can prioritize and incentivize flood-proofing of homes, neighborhoods, and key infrastructure, such as sewer and stormwater systems. • Avoid putting anything new in harm’s way. Communities can use a range of regulatory and planning tools to curtail new development in coastal locations subject to tidal flooding now and in the future. • Consider the risks and benefits of adaptation measures. Some measures to limit the impact of coastal flooding can provide multiple benefits, while others can alter shoreline dynamics and damage neighboring areas and ecosystems. Decision makers need to ensure that a rush to protect coastal communities builds broad-based resilience, rather than helping some areas while putting others at risk. • Develop a long-term vision. Communities that create a vision for both near-term protection and long-term resilience in the face of sea level rise—and craft plans for building better, safer, and more equitably—will be best positioned to thrive in the years ahead. . . . AND A NATIONAL ONE But local communities can’t go it alone—coastal challenges are too great, the costs are too steep, and too many people are at risk. Instead, we need a coordinated, well-funded national response to our country’s coastal vulnerability involving federal, state, and local collaboration. Federal and state governments can help build local resilience by supporting, incentivizing, regulating, and even mandating action. They can: • Build and maintain a coastal monitoring and data-sharing system equal to the threat. Key federal agencies can sustain and expand efforts to monitor and project sea level rise and flooding, and ensure that local decision makers have access to the data. • Encourage or mandate the use of good scientific information. Agencies can require that communities and other applicants for state and federal funds use the best available data, and demonstrate that new development and redevelopment projects can withstand projected tidal flooding and storm surges. • Support planning. More federal support for state and local planning and collaboration can accelerate efforts to build coastal resilience. • Mobilize funding. Adapting to sea level rise will require major, sustained investment. Federal policy makers need to develop new funding sources to support resilience-building efforts at the state and local level. • Improve risk management. The true costs of living on the coast are not reflected in the price of flood insurance and other risk management tools. But big increases in the cost of insurance are hard for many to bear. Federal incentives to reduce some property owners’ risks and costs can aid the transition to a more solvent flood insurance system and better risk management. • Ensure equitable investments. Federal investments in coastal resilience can prioritize households and communities with the greatest needs. • Reduce heat-trapping emissions. A near-term increase in sea level rise and tidal flooding may be locked in, but changes later this century and beyond are not fixed. To slow the rate of sea level rise—and enable coastal communities to adapt in affordable and manageable ways— we must reduce our global warming emissions.”
  • Thumbnail Image
    Item
    Floods of June 2012 in Northeastern Minnesota
    (2012) Czuba, Christiana R; Fallon, James D; Kessler, Eric W
    This report is a summary description of the 2012 flooding in the Fond du Lac region of Lake Superior from a meteorological and hydrologic perspective. The report notes that the extent and depth of flooding in communities can be used for flood recovery efforts. Key points are reproduced below. Abstract: “During June 19–20, 2012, heavy rainfall, as much as 10 inches locally reported, caused severe flooding across northeastern Minnesota. The floods were exacerbated by wet antecedent conditions from a relatively rainy spring, with May 2012 as one of the wettest Mays on record in Duluth. The June 19–20, 2012, rainfall event set new records in Duluth, including greatest 2-day precipitation with 7.25 inches of rain. The heavy rains fell on three major watersheds: the Mississippi Headwaters; the St. Croix, which drains to the Mississippi River; and Western Lake Superior, which includes the St. Louis River and other tributaries to Lake Superior. Widespread flash and river flooding that resulted from the heavy rainfall caused evacuations of residents, and damages to residences, businesses, and infrastructure. In all, nine counties in northeastern Minnesota were declared Federal disaster areas as a result of the flooding. Peak-of-record streamflows were recorded at 13 U.S. Geological Survey stream gages as a result of the heavy rainfall. Flood-peak gage heights, peak streamflows, and annual exceedance probabilities were tabulated for 35 U.S. Geological Survey stream gages. Flood-peak streamflows in June 2012 had annual exceedance probabilities estimated to be less than 0.002 (0.2 percent; recurrence interval greater than 500 years) for five stream gages, and between 0.002 and 0.01 (1 percent; recurrence interval greater than 100 years) for four stream gages. High-water marks were identified and tabulated for the most severely affected communities of Barnum (Moose Horn River), Carlton (Otter Creek), Duluth Heights neighborhood of Duluth (Miller Creek), Fond du Lac neighborhood of Duluth (St. Louis River), Moose Lake (Moose Horn River and Moosehead Lake), and Thomson (Thomson Reservoir outflow near the St. Louis River). Flood-peak inundation maps and water-surface profiles were produced for these six severely affected communities. The inundation maps were constructed in a geographic information system by combining high-water-mark data with high-resolution digital elevation model data. The flood maps and profiles show the extent and depth of flooding through the communities and can be used for flood response and recovery efforts by local, county, State, and Federal agencies.”
  • Thumbnail Image
    Item
    Northeast Minnesota Flash Flood Disaster - Economic Development Impact Study
    (2013) Arrowhead Regional Development Commission
    ARDC conducted a study to determine economic development impacts of the 2012 flood. ARDC collected information from all levels of government and held small group interviews to analyze gaps in data and identify lessons learned. Recommendations are paraphrased and summarized below. “A. Develop and Mobilize Micro Loans and Micro Grants for Disaster Response and Recovery. Micro loans and micro grants have been identified as a best practice for providing quick assistance to small businesses. The Northland Foundation’s Business Flood Recovery Fund has been cited as one of the most successful local response efforts following the 2012 floods. The program should be evaluated to learn how the region can keep the basic infrastructure of this program in place and how other groups can duplicate it or enhance it so that it can be remobilized even quicker in the aftermath of a future disaster. Micro loans should be explored as a source of assistance immediately following a disaster. Regional economic development funds, revolving loan funds and additional commercial lenders should examine their capacity and adopt disaster recovery lending programs that could be enacted immediately after future disasters. B. Maximize Planning and Zoning for Disaster Mitigation, Response, Recovery and Resiliency. 1. Land Use Planning: Decisions made before and after a disaster affect the resiliency and recovery of a community in the event of a disaster. Communities that integrate disaster resiliency into land use planning and development decisions can mitigate potential disaster impacts by: a. Integrating a hazard element into Comprehensive Plans, either as a stand-alone section or in discussion of other plan sections such as housing, infrastructure, and economic development. b. Assessing disaster vulnerability of sites in development plans. c. Encouraging development in less hazardous areas. d. Minimizing or mitigating vulnerable types of development in hazardous areas. e. Reducing disaster vulnerability through land use and zoning regulations. 2. Economic Development Planning. Recovery dictates long term success. The return of jobs, tourism, and capital investments are dependent on housing recovery, infrastructure restoration, environmental restoration, and social service provision. Communities should integrate disaster resiliency into economic development planning by: a. Assessing the unique needs and challenges for small businesses, large employers, economic diversification, and workforce/residents in the face of a disaster. b. Prioritizing economic development projects that are disaster resilient and fill a need in the post disaster community. c. Encouraging all physical projects to address disaster resiliency in the planning stage. 3. Infrastructure and Public Facilities: Restoration of infrastructure and public facilities is a prerequisite for recovery. Communities should prioritize long term infrastructure needs to take advantage of opportunity to upgrade, mitigate, or relocate infrastructure following a disaster. In the rush to rebuild, communities should be prepared to avoid repeating mistakes or missing opportunities to develop systems that will serve their residents and businesses better in the future. A disaster resiliency factor should be added to routine capital project planning. 4. Planning and Recovery Facilitation: To support community planning for and recovery from disasters, ARDC is available to work with communities on a project basis to: a. Offer a forum to convene diverse stakeholders and facilitate discussion and planning initiatives around the issues of economic resiliency and preparedness. b. Provide communities and businesses with regional demographic and economic data, hazard vulnerability and mitigation data, and disaster impact data. c. Establish familiarity with economic and community recovery funding sources and programs. d. Explore how ARDC’s revolving loan fund can be used to assist disaster impacted businesses. C. Improve information cataloging for long - term recovery and resiliency ARDC found that a lack of a one - stop portal for information on the evolving economic impact of the disaster is a challenge to long term planning and recovery efforts. A one - stop data repository may be best set up at the county and state levels. An up – to - date data repository can be useful for: • Developing and securing funding for recovery and resiliency programs and assessing the effectiveness of mitigation programs. (TIF districts, redevelopment programs, business continuity planning) • Establishing baseline to assess the long -term issues presented by future disasters in the region or elsewhere in the state. • Developing new local, regional, and state policies and programs. • Developing disaster profiles for use in community planning. • Developing tools and metrics for evaluating progress against set goals, objectives and milestones.
  • Thumbnail Image
    Item
    Three-Dimensional Simulation of Bridge Foundation Scour on Mississippi River Bridges 9321 & 27801
    (Center for Transportation Studies, University of Minnesota, 2016-02) Sotiropoulos, Fotis; Khosronejad, Ali
    We present data-driven numerical simulations of 100- and 500-year floods events in the Mississippi River at its intersection with the Highway I-694 by coupling coherent-structure resolving hydrodynamics with bed morphodynamics under live-bed conditions. The study area is about 1.7 miles long and 220 yard wide reach of the Upper Mississippi River, near Minneapolis MN, which contains several natural islands and man-made hydraulic structures. We employ the large-eddy simulation (LES) and bed-morphodynamic modules of the Virtual Flow Simulator (VFS-Rivers) model, a recently developed in-house code, to investigate the flow and bed evolution of the river along the reach and near the bridge piers BR 27801 and BR 932. We integrate data from airborne Light Detection and Ranging (LiDAR), sub-aqueous sonar apparatus on-board a boat and total station survey to construct a digital elevation model of the river bathymetry and surrounding flood plain, including islands and bridge piers. A field campaign under base-flow condition is also carried out to collect mean flow measurements via Acoustic Doppler Current Profiler (ADCP) to validate the hydrodynamic module of the VFS-Rivers model. Our simulation results for the bed evolution of the river under the 100- and 500-year flood reveal complex sediment transport dynamics near the bridge piers consisting of both scour and refilling events due to the continuous passage of sand dunes. A brief description of the findings in terms of maximum scour depth around individual bridge piers can be found in the executive summary of the report.
  • Thumbnail Image
    Item
    Urban Flooding in the Great Lakes States: A Municipality/Utility Survey Report
    (2012-07) Center for Neighborhood Technology
    As part of our Smart Water for Smart Regions initiative, the Center for Neighborhood Technology (CNT) is working with communities across Great Lakes states to alleviate urban flooding. The purpose of this survey is to develop an understanding of the effect of flooding on Great Lakes cities and to identify strategies to manage the problem. By providing a baseline of practices and policies among municipal stormwater/sewer utilities, the survey results are intended to support collaborative initiatives for dealing with flooding. Our survey, the first of its kind in the Great Lakes, found that municipalities and stormwater utilities face significant challenges. The 30 survey respondents serve 330 municipalities with a population of approximately 19.7 million people—nearly 23 percent of the total population of the Great Lakes states and province.4 All 30 respondents received flooding complaints, with 80 percent characterizing the annual number of complaints as medium or large. Stormwater is flooding into people’s backyards, streets, and parking lots (90 percent of respondents said), into the interior of buildings through sewer backups (83.3 percent), and through the walls of homes and buildings (46.7 percent).