Friday Facts, March 26, 2010, Vol. 54

Bureau of Nutrition and Health Promotion part of the Iowa Department of Public Health produces of weekly newsletter about the Iowa WIC Program for the State of Iowa citizen.

Council Bluffs Interstate System Improvements Project Pottawatomie County, Iowa and Douglas County, Nebraska Project Number: IM-029-3(62)54-13-78, November 2004

The Iowa Department of Transportation (Iowa DOT), Nebraska Department of Roads (NDOR), and the Federal Highway Administration (FHWA) are proposing to improve the interstate system around Council Bluffs with improvements extending across the Missouri River on I-80 to east of the I-480 interchange in Omaha, Nebraska, see Figure 1-1. The study considers long-term, broad-based transportation improvements along I-80, I-29, and I-480, including approximately 18 mainline miles of interstate and 14 interchanges (3 system1, 11 service), that would add capacity and correct functional issues along the mainline and interchanges and upgrade the I-80 Missouri River Crossing. These improvements, once implemented, would bring the segments of I-80 and I-29 up to current engineering standards and modernize the roadway to accommodate future traffic needs. In 2001, Iowa DOT and FHWA initiated the Council Bluffs Interstate System (CBIS) Improvements Project. The agencies concluded that the environmental study process would be conducted in two stages; that is, a tiered approach would be applied. The project is being conducted pursuant to the National Environmental Policy Act (NEPA) regulations issued by the Council on Environmental Quality (CEQ), 40 Code of Federal Regulations (CFR) Part 1502.20, and FHWA 23 CFR Part 771.111, that permit tiering for large, complex NEPA studies. Tier 1 is an examination of the overall interstate system improvement needs, including a clear explanation of the area’s transportation needs, a study of alternatives to satisfy them, and broad consideration of potential environmental and social impacts. The Tier 1 evaluation is at a sufficient level of engineering and environmental detail to assist decision makers in selecting a preferred transportation strategy. Tier 1 includes preparation of a draft and final Environmental Impact Statement (EIS) that would disclose the potential environmental and social effects (evaluated at a planning level that considers a variety of conceptual designs) of the proposed improvements. The final EIS will conclude with a Record of Decision (ROD) that states the preferred plan for improvements to be implemented. Essentially, the Tier 1 document will establish the planning framework for the needed improvements. Because the scope of the overall system improvements is large, the interstate improvements would be implemented as a series of individual projects that fit into the overall planning framework. The Tier 1 Area of Potential Impact, which is discussed in detail in Section 4 is an alternative that considers a combination of the most reasonable concepts that have been developed, buffered by approximately 100 or more feet to ensure that any Tier 2 design modifications would remain inside the outer boundary.

Evaluation of High-Slump Concrete for Bridge Deck Overlays, TR-427, 2005

The Iowa Method for bridge deck overlays has been very successful in Iowa since its adoption in the 1970s. This method involves removal of deteriorated portions of a bridge deck followed by placement of a layer of dense (Type O) Portland Cement Concrete (PCC). The challenge encountered with this type of bridge deck overlay is that the PCC must be mixed on-site, brought to the placement area and placed with specialized equipment. This adds considerably to the cost and limits contractor selection, because not all contractors have the capability or equipment required. If it is possible for a ready-mix supplier to manufacture and deliver a dense PCC to the grade, then any competent bridge deck contractor would be able to complete the job. However, Type O concrete mixes are very stiff and generally cannot be transported and placed with ready-mix type trucks. This is where a “super-plasticizer” comes in to use. Addition of this admixture provides a substantial increase in the workability of the concrete – to the extent that it can be delivered to the site and placed on the deck directly out of a ready-mix truck. The objective of this research was to determine the feasibility of placing a deck overly of this type on county bridges within the limits of county budgets and workforce/contractor availability.

Water Summary Update, July 10, 2015, No. 54

A snapshot of water resource trends prepared by the Iowa DNR in collaboration with the Iowa Department of Agriculture and Land Stewardship, the U.S. Geological Survey, and The Iowa Homeland Security and Emergency Management Department.