Fact Sheet: Winter Driving, 2011

The leading cause of death during winter storms is transportation accidents. Preparing your vehicle for the winter season and knowing how to react if stranded or lost on the road are the keys to safe winter driving.

State of Iowa Long-Term Economic Recovery Strategy Prepared for the Economic Development Administration, U.S. Department of Commerce, October 2010

The Rebuild Iowa Office (RIO) continues to coordinate the state‘s recovery effort from the storms, tornadoes and floods of 2008. Much has been accomplished since the Office‘s last quarterly report was issued in July 2010. State funding has been disbursed to help Iowans with unmet needs and housing. Local governments and entities are utilizing millions of federal dollars so thousands of disaster-impacted homeowners can be offered a buyout. More infrastructure projects are under construction and new neighborhoods are being built with mitigation efforts in mind. However, as Iowa continues to celebrate many successes along the road to recovery, it must also address the numerous challenges that are encountered along the path. Recovering from the state‘s largest disaster must be looked at as a marathon, not a sprint. Over the past three months, the RIO has especially remained focused on helping small business owners impacted by the 2008 disasters. Many disaster-affected businesses have reopened their doors, however their debt load continues to be overwhelming and many still struggle with the timeliness of the disbursement of funds. This report describes how programs and recent modifications are working to assist recovering businesses. This report contains updates on housing progress while outlining the complexities behind certain programs and the bottlenecks communities are facing due to strict federal guidelines for implementation. This following pages also describe how Iowa is implementing Smart Planning principles, publicizing flood awareness through outreach efforts and preparing a blueprint for the state to follow when future disasters occur. As always, the RIO recognizes and thanks the countless leaders and front-line workers from local, regional, state and federal government, businesses, non-profit organizations and private citizens that have provided input, support and leadership. Their dedication to Iowa‘s disaster recovery has made the plans and projects on the following pages possible.

Development of Self-Cleaning Box Culvert Design – Phase II, TR-619, 2013

Culverts are common means to convey flow through the roadway system for small streams. In general, larger flows and road embankment heights entail the use of multibarrel culverts (a.k.a. multi-box) culverts. Box culverts are generally designed to handle events with a 50-year return period, and therefore convey considerably lower flows much of the time. While there are no issues with conveying high flows, many multi-box culverts in Iowa pose a significant problem related to sedimentation. The highly erosive Iowa soils can easily lead to the situation that some of the barrels can silt-in early after their construction, becoming partially filled with sediment in few years. Silting can reduce considerably the capacity of the culvert to handle larger flow events. Phase I of this Iowa Highway Research Board project (TR-545) led to an innovative solution for preventing sedimentation. The solution was comprehensively investigated through laboratory experiments and numerical modeling aimed at screening design alternatives and testing their hydraulic and sediment conveyance performance. Following this study phase, the Technical Advisory Committee suggested to implement the recommended sediment mitigation design to a field site. The site selected for implementation was a 3-box culvert crossing Willow Creek on IA Hwy 1W in Iowa City. The culvert was constructed in 1981 and the first cleanup was needed in 2000. Phase II of the TR 545 entailed the monitoring of the site with and without the selfcleaning sedimentation structure in place (similarly with the study conducted in laboratory). The first monitoring stage (Sept 2010 to December 2012) was aimed at providing a baseline for the operation of the as-designed culvert. In order to support Phase II research, a cleanup of the IA Hwy 1W culvert was conducted in September 2011. Subsequently, a monitoring program was initiated to document the sedimentation produced by individual and multiple storms propagating through the culvert. The first two years of monitoring showed inception of the sedimentation in the first spring following the cleanup. Sedimentation continued to increase throughout the monitoring program following the depositional patterns observed in the laboratory tests and those documented in the pre-cleaning surveys. The second part of Phase II of the study was aimed at monitoring the constructed self-cleaning structure. Since its construction in December 2012, the culvert site was continuously monitored through systematic observations. The evidence garnered in this phase of the study demonstrates the good performance of the self-cleaning structure in mitigating the sediment deposition at culverts. Besides their beneficial role in sediment mitigation, the designed self-cleaning structures maintain a clean and clear area upstream the culvert, keep a healthy flow through the central barrel offering hydraulic and aquatic habitat similar with that in the undisturbed stream reaches upstream and downstream the culvert. It can be concluded that the proposed self-cleaning structural solution “streamlines” the area upstream the culvert in a way that secures the safety of the culvert structure at high flows while producing much less disturbance in the stream behavior compared with the current constructive approaches.

Floods of July 19-25, 1999, in the Wapsipinicon and Cedar River Basins, Northeast Iowa, HR-140

Severe flooding occurred during July 19-25, 1999, in the Wapsipinicon and Cedar River Basins following two thunderstorms over northeast Iowa. During July 18-19, as much as 6 inches ofrainfall was centered over Cerro Gordo, Floyd, Mitchell, and Worth Counties. During July 20-21, a second storm occurred in which an additional rainfall of as much as 8 inches was centered over Chickasaw and Floyd Counties. The cumulative effect of the storms produced floods with new maximum peak discharges at the following streamflow-gaging stations: Wapsipinicon River near Tripoli, 19,400 cubic feet per second; Cedar River at Charles City, 31,200 cubic feet per second (recurrence interval about 90 years); Cedar River at Janesville, 42,200 cubic feet per second (recurrence interval about 80 years); and Flood Creek near Powersville, 19,000 cubic feet per second. Profiles of flood elevations for the July 1999 flood are presented in this report for selected reaches along the Wapsipinicon, Cedar, and Shell Rock Rivers and along Flood Creek. Information about the river basins, rain storms, and flooding are presented along with information on temporary bench marks and reference points in the Wapsipinicon and Cedar River Basins.

Floods of May 17-20, 1999, in the Volga and Wapsipinicon River Basins, Northeast Iowa, HR-140

Record flooding occurred May 17-20, 1999, in the Volga and Wapsipinicon River Basins following thunderstorm activity over northeast Iowa. On Sunday, May 16, between 6 and 8 inches of rain fell during a 24- hour period over portions of Bremer, Butler, and Fayette Counties. Highest rainfall during this 24-hour period was 8.3 inches recorded north of Oelwein in southwest Fayette County. A peak discharge of 29,800 cubic feet per second in the Volga River at Mederville, 53,900 cubic feet per second in the Turkey River at Garber, and 31, 100 cubic feet per second in the Wapsipinicon River at Independence set new peak discharge records. The peak discharge at Garber was greater than a theoretical 500-year flood, and the peak discharge at Independence was the equivalent of a 90- year flood. Information about the basins, rain storms, flooding, and a profile of high water marks are presented for selected intervals along the Volga River, Wapsipinicon River, Crane Creek, Little Wapsipinicon River, and Otter Creek.

Flood of June 15-17, 1998, Nishnabotna and East Nishnabotna Rivers, Southwest Iowa, HR-140

Record flooding occurred June 15-17, 1998, in the Nishnabotna and East Nishnabotna River basins following severe thunderstorm activity over southwest Iowa. More than 8 inches of rain fell over a large part of Cass County. The rain gage at Atlantic, Iowa recorded a 24-hour total rainfall of 13.18 inches, which established a new official State record for the greatest amount of rainfall in a 24-hour period. The peak discharge was 41,400 cubic feet per second in the East Nishnabotna River near Atlantic, 60,500 cubic feet per second in the East Nishnabotna River at Red Oak, and 65,100 cubic feet per second in the Nishnabotna River above Hamburg. The peak discharge at Atlantic was greater than the theoretical 200-year flood and the peak discharges at Red Oak and Hamburg were greater than the respective theoretical 500-year floods. Information about the basin, the rain storms, the flooding, and a profile of high water marks at selected intervals along the Nishnabotna and East Nishnabotna Rivers are presented in this report.

Evaluation of Brisco Scour Monitors, HR-551, 1993

Two Brisco Scour Monitors were installed on pier MS1 of the Mississippi River at Burlington in August 1991. No problems were encountered during the installation. The monitors consist of a probe resting on the river bottom fastened to a cable that wraps around a reel. An electrical system monitors the movement of the reel which transmits to a digital readout which shows whether scour has occurred. The intent was to monitor the digital readout twice a year during a four-year evaluation period. The scour monitor digital readouts malfunctioned frequently due to electrical storms. The scour monitor performance was completely unacceptable.

Wind Tunnel Analysis of the Effects of Planting at Highway Grade Separation Structures, HR-202, 1979

Blowing and drifting snow has been a problem for the highway maintenance engineer virtually since the inception of the automobile. In the early days, highway engineers were limited in their capability to design and construct drift free roadway cross sections, and the driving public tolerated the delays associated with snow storms. Modern technology, however, has long since provided the design expertise, financial resources, and construction capability for creating relatively snowdrift free highways, and the driver today has come to expect a highway facility that is free of snowdrifts, and if drifts develop they expect highway maintenance crews to open the highway within a short time. Highway administrators have responded to this charge for better control of snowdrifting. Modern highway designs in general provide an aerodynamic cross section that inhibits the deposition of snow on the roadway insofar as it is economically feasible to do so.

Are You Prepared? A Guide to Emergency Preparedness, October 24, 2013

Being prepared means making an emergency plan, building an emergency kit and being aware of the hazards that can impact you. Whether you are at home or at work, emergencies like tornadoes, flooding or winter storms can occur quickly and without warning. We can’t prevent emergencies, but we can prepare for them.

Crisis Kit for Teacher and Administrators, January 17, 2012

Whether it’s tornadoes, flooding, winter storms or an act of terrorism, emergencies can occur quickly and without warning. Although we cannot prevent emergencies, we can prepare for them. Teachers and administrators need to take special care as they are responsible for the students in their care. Putting together and having on hand a crisis kit can be invaluable in times of emergency.

Winter Driving A Guide for Your Safety, January 17, 2012

The leading cause of death during winter storms is transportation accidents. Preparing your vehicle for the winter season and knowing how to react if stranded or lost on the road are the keys to safe winter driving.

Winter Weather A guide for Your Safety, January 17, 2012

A major winter storm can be lethal. Preparing for cold weather conditions and responding to them effectively can reduce the dangers caused by winter storms.

Optimization of Snow Drifting Mitigation and Control Methods for Iowa Conditions Part II, TR-626, 2015

Blowing and drifting of snow is a major concern for transportation efficiency and road safety in regions where their development is common. One common way to mitigate snow drift on roadways is to install plastic snow fences. Correct design of snow fences is critical for road safety and maintaining the roads open during winter in the US Midwest and other states affected by large snow events during the winter season and to maintain costs related to accumulation of snow on the roads and repair of roads to minimum levels. Of critical importance for road safety is the protection against snow drifting in regions with narrow rights of way, where standard fences cannot be deployed at the recommended distance from the road. Designing snow fences requires sound engineering judgment and a thorough evaluation of the potential for snow blowing and drifting at the construction site. The evaluation includes site-specific design parameters typically obtained with semi-empirical relations characterizing the local transport conditions. Among the critical parameters involved in fence design and assessment of their post-construction efficiency is the quantification of the snow accumulation at fence sites. The present study proposes a joint experimental and numerical approach to monitor snow deposits around snow fences, quantitatively estimate snow deposits in the field, asses the efficiency and improve the design of snow fences. Snow deposit profiles were mapped using GPS based real-time kinematic surveys (RTK) conducted at the monitored field site during and after snow storms. The monitored site allowed testing different snow fence designs under close to identical conditions over four winter seasons. The study also discusses the detailed monitoring system and analysis of weather forecast and meteorological conditions at the monitored sites. A main goal of the present study was to assess the performance of lightweight plastic snow fences with a lower porosity than the typical 50% porosity used in standard designs of such fences. The field data collected during the first winter was used to identify the best design for snow fences with a porosity of 50%. Flow fields obtained from numerical simulations showed that the fence design that worked the best during the first winter induced the formation of an elongated area of small velocity magnitude close to the ground. This information was used to identify other candidates for optimum design of fences with a lower porosity. Two of the designs with a fence porosity of 30% that were found to perform well based on results of numerical simulations were tested in the field during the second winter along with the best performing design for fences with a porosity of 50%. Field data showed that the length of the snow deposit away from the fence was reduced by about 30% for the two proposed lower-porosity (30%) fence designs compared to the best design identified for fences with a porosity of 50%. Moreover, one of the lower-porosity designs tested in the field showed no significant snow deposition within the bottom gap region beneath the fence. Thus, a major outcome of this study is to recommend using plastic snow fences with a porosity of 30%. It is expected that this lower-porosity design will continue to work well for even more severe snow events or for successive snow events occurring during the same winter. The approach advocated in the present study allowed making general recommendations for optimizing the design of lower-porosity plastic snow fences. This approach can be extended to improve the design of other types of snow fences. Some preliminary work for living snow fences is also discussed. Another major contribution of this study is to propose, develop protocols and test a novel technique based on close range photogrammetry (CRP) to quantify the snow deposits trapped snow fences. As image data can be acquired continuously, the time evolution of the volume of snow retained by a snow fence during a storm or during a whole winter season can, in principle, be obtained. Moreover, CRP is a non-intrusive method that eliminates the need to perform man-made measurements during the storms, which are difficult and sometimes dangerous to perform. Presently, there is lots of empiricism in the design of snow fences due to lack of data on fence storage capacity on how snow deposits change with the fence design and snow storm characteristics and in the estimation of the main parameters used by the state DOTs to design snow fences at a given site. The availability of such information from CRP measurements should provide critical data for the evaluation of the performance of a certain snow fence design that is tested by the IDOT. As part of the present study, the novel CRP method is tested at several sites. The present study also discusses some attempts and preliminary work to determine the snow relocation coefficient which is one of the main variables that has to be estimated by IDOT engineers when using the standard snow fence design software (Snow Drift Profiler, Tabler, 2006). Our analysis showed that standard empirical formulas did not produce reasonable values when applied at the Iowa test sites monitored as part of the present study and that simple methods to estimate this variable are not reliable. The present study makes recommendations for the development of a new methodology based on Large Scale Particle Image Velocimetry that can directly measure the snow drift fluxes and the amount of snow relocated by the fence.

Performance Measurement for Highway Winter Maintenance Operations, TR-491, 2009

The goal of this research project was to develop a method to measure the performance of a winter maintenance program with respect to the task of providing safety and mobility to the travelling public. Developing these measures required a number of steps, each of which was accomplished. First, the impact of winter weather on safety (crash rates) and mobility (average vehicle speeds were measured by a combination of literature reviews and analysis of Iowa Department of Transportation traffic and Road Weather Information System data. Second, because not all winter storms are the same in their effects on safety and mobility, a method had to be developed to determine how much the various factors that describe a winter storm actually change safety and mobility. As part of this effort a storm severity index was developed, which ranks each winter storm on a scale between 0 (a very benign storm) and 1 (the worst imaginable storm). Additionally a number of methods of modeling the relationships between weather, winter maintenance actions and road surface conditions were developed and tested. The end result of this study was a performance measure based on average vehicle speed. For a given class of road, a maximum expected average speed reduction has been identified. For a given storm, this maximum expected average speed reduction is modified by the storm severity index to give a target average speed reduction. Thus, if for a given road the maximum expected average speed reduction is 20 mph, and the storm severity for a particular storm is 0.6, then the target average speed reduction for that road in that storm is 0.6 x 20 mph or 12 mph. If the average speed on that road during and after the storm is only 12 mph or less than the average speed on that road in good weather conditions, then the winter maintenance performance goal has been met.

1245-02IJ West Tarkio Final Report

Initiated in 2001, the West Tarkio Creek Watershed Project has a proven track record of implementing an enormous amount of structural conservation practices. To date, over $925,000 has been spent to build 69 miles of terraces on 63 cooperators' land. The success of the Project was due in large part to the conservation ethic of the landowners to improve their farms, preserve the productivity of the land, and protect West Tarkio Creek. This has been made possible through funding from DSC Watershed Protection Funds (WSPF) which has provided $1,362,592 in cost share funds since 2001 but is has been severely limited in recent years due to shortages within the State’s budget. The original project goals called for the construction of 750,000 feet (142 miles) of terraces to effectively treat the watershed. In order to meet these goals and bring the project to a successful endpoint, another 153,000 feet (29 miles) remain to be constructed by the landowners with the help of the SWCD staff. Severe rain events in recent years have caused an enormous amount of damage throughout the region, these storms were helpful in identifying where watershed work remains to be completed. Scars on the landscape in the aftermath of the storms clearly etched out the specific location where additional practices are needed in addition to those proposed in the original project work plan. Project supporters are confident that the WIRB Program can unlock this potential and pave the way for what can become known as one of the most effective land treatment projects in Iowa.