NCHRP 2017 Annual Report (2017)

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18 STAFF NEWS New NCHRP Manager In late 2016, TRB was pleased to announce Lori Sundstrom as the new manager of NCHRP. In this role, she is responsible for the overall opera- tion and oversight of NCHRP. Sundstrom has been with TRB since 2007, serving as senior program officer prior to this position. Before joining TRB, Sundstrom held management and executive positions with the Oregon DOT, the Portland (Oregon) Development Commission, and the city of Phoenix, Arizona. She holds a Master of Public Administra- tion from Arizona State University and a Bachelor of Science in Business Administration from the University of Arizona.

FOCUS ON: NCHRP Research Report 840 August 2017 R E A D Y R E S U L T S Next Steps to Put NCHRP Research into Practice EVALUATE Communicate with state regulatory agencies to evaluate whether the watershed approach is a viable option in your state. COLLABORATE Many agencies within a state have an interest in water quality. Work with these other agencies to develop practices that align with each agency’s mission, goals, and responsibilities. REVIEW To help determine watershed priorities, review existing planning documents from federal, state, and local entities. NETWORK Contact other states that have considered or implemented a watershed approach. PARTNER Apply for NCHRP implementation funding. See trb.org/nchrp. NEXT STEPS Put It into Practice REAL-WORLD NEED Most DOTs manage stormwater runoff from highway facilities on a project-by-project basis. Typically, this means using stormwater best management practices (BMPs), such as vegetated swales and retention ponds, near construction sites. But many locations, particularly in urban areas, have limited space in the right-of-way, which can make constructing stormwater facilities difficult and expensive. As a cost-effective alternative to traditional stormwater BMPs, agencies are increasingly interested in using a watershed approach, which takes into account the ecosystem of an entire area drained by a single waterway. By installing stormwater facilities not just on project sites but elsewhere in the watershed, DOTs can achieve the same and sometimes better environmental benefits for the same or lower costs. However, it is not always clear which BMPs to use—or where to place them within the watershed—to achieve the maximum benefit. RESEARCH SOLUTION NCHRP Project 25-37 developed a Microsoft Excel–based tool, the Watershed- Based Stormwater Mitigation Toolbox, to help transportation agencies compare and select stormwater BMPs. The Toolbox takes into account the overall impact on watershed health of both runoff facilities that are on specific project sites and those elsewhere within the watershed. Agencies can customize the tool to their environmental priorities and local conditions. The Toolbox also provides scientific support for a watershed-based approach that agencies can use as they work with regulators to make stormwater management decisions. New Tool Supports Watershed- Based Stormwater Management Where road construction sites do not allow for use of stormwater treatment methods such as the vegetated swale shown here, a watershed-wide approach to stormwater runoff can be a cost-effective and environmentally beneficial alternative. Im ag e co ur te sy o f M in ne so ta D O T

About the Research WHAT WE LEARNED Four stormwater factors are critically important to watershed health: (1) total suspended solids; (2) nutrient content, which can encourage algae blooms that deplete oxygen for other aquatic species; (3) runoff volume; and (4) increased stream power, which can contribute to erosion and sediment transport. However, these factors don’t affect all watersheds in the same way, and their relative importance varies with local conditions. The Toolbox allows users to prioritize the four performance measures by assigning specific weights to them. The tool then ranks stormwater BMPs based on how effective they are at improving the conditions that best support local priorities. WHY IT MATTERS The Toolbox provides a starting point for taking a holistic watershed approach to stormwater management and comparing on- and off-site treatment options. During the planning phase of transportation projects, agencies can use the Toolbox to help characterize watersheds and prioritize potential stormwater BMPs. Every state’s regulatory environment is unique, and state regulators’ ability to consider a watershed approach will vary. Consequently, the Toolbox can also provide agencies with valuable scientific support for taking a watershed approach to meet regulatory requirements. NCHRP PROJECT 25-37 FINAL PRODUCTS NCHRP Research Report 840: A Watershed Approach to Mitigating Stormwater Impacts trb.org/Main/Blurbs/175861.aspx Watershed-Based Stormwater Mitigation Toolbox trb.org/Main/Blurbs/175861.aspx NCHRP SENIOR PROGRAM OFFICER Lori Sundstrom | lsundstrom@nas.edu PRINCIPAL INVESTIGATOR Neil Weinstein | nweinstein@lidcenter.org ADDITIONAL RESOURCES EnviroAtlas, U.S. Environmental Protection Agency epa.gov/enviroatlas Web Soil Survey, Natural Resources Conservation Service websoilsurvey.sc.egov.usda.gov National Centers for Environmental Information weather and climate data ncdc.noaa.gov/data-access/quick-links August 2017 N C H R P R E A D Y R E S U L T S RESEARCH STRATEGY Investigators began by identifying watershed data from national agencies that could be used to assess the baseline health of a watershed. Investigators then identified the performance measures most critical to watershed health and the relative effectiveness of various BMPs in maintaining or improving such measures. Using this information, researchers developed a methodology for evaluating and comparing BMPs. This methodology departs from a project-based approach, which generally focuses on specific pollutants. Instead, it analyzes ecosystem services, or the benefits and uses that a watershed provides to its community, such as providing a drinking water supply or a habitat for a commercial fishery. Inves- tigators incorporated that methodology into the Watershed-Based Stormwater Mitigation Toolbox. RESOURCES The Transportation Research Board’s National Cooperative Highway Research Program (NCHRP) produces ready-to-implement solutions to the challenges facing transportation professionals. NCHRP is sponsored by the individual state departments of transportation of the American Association of State Highway and Transportation Officials (AASHTO), in cooperation with the Federal Highway Administration (FHWA). Any opinions and conclusions expressed or implied in resulting research products are those of the individuals and organizations who performed the research and are not necessarily those of TRB; the National Academies of Sciences, Engineering, and Medicine; or NCHRP sponsors. Im ag e co ur te sy o f W as hi ng to n St at e D O T (C C BY -N C- N D 2 .0 ) TRANSPORTATION RESEARCH BOARD Downstream wetland restoration is an off-site BMP that can be used as part of a watershed- scale approach to mitigating pollution impacts from construction activities. Im ag e co ur te sy o f U .S . F ish a nd W ild lif e Se rv ic e

FOCUS ON: NCHRP Project 12-100 July 2017 R E A D Y R E S U L T S Next Steps to Put NCHRP Research into Practice REVIEW Consult the guidelines developed through this project for guidance on small-movement expansion joint (SMEJ) installation, evaluation, and repair. EVALUATE Consider incorporating SMEJs into your state’s existing bridge-element inspection practices. SELECT Use performance metrics to select replacement joint types based on a bridge’s traffic levels, environmental conditions, and expected service life. COLLABORATE Review procedures and bridge design and inspection manuals used by other states, and share practices when appropriate. PARTNER Apply for NCHRP implementation funding. See trb.org/nchrp. NEXT STEPS Put It into Practice REAL-WORLD NEED Small-movement expansion joints (SMEJs) are a small part of short-span bridges, but they have a big impact on the bridge’s life cycle. SMEJs let the bridge accommodate movements caused by temperature changes and rotation, while also directing water and deicing chemicals off the deck and away from the bridge. However, without proper maintenance, SMEJs can develop defects that allow deicers to leak into the bridge superstructure and substructure. These chemicals can cause serious problems that are expensive to repair, such as steel girder corrosion and embankment erosion. Improper sizing of the joint seal, poor substrate preparation, and improper application have been cited as some of the reasons for expansion joint failures. To overcome these failure mechanisms, bridge owners need clear guidelines for evaluating the performance of bridge expansion joints and maintaining them. RESEARCH SOLUTION Investigators used a literature review, surveys of stakeholders, and the expertise of the project panel to develop SMEJ maintenance, repair, and replacement guidelines. These guidelines cover all five common SMEJ types, providing illustrated repair and installation procedures, formulas to help select and install joints, and a method to test the watertightness of joints. Agencies can use these guidelines to improve SMEJ maintenance procedures and reduce bridge damage caused by joint defects. Extending Bridge Life by Maintaining Expansion Joints Expansion joints help bridges accommodate small movements caused by temperature changes. Proper maintenance keeps the joints watertight, which prevents deicers from leaking into the bridge and causing corrosion. So ur ce : W ik ip ed ia

About the Research WHAT WE LEARNED Strip seals are the most widely used type of SMEJ today, although asphalt plug joints, compression and bonded joints, pourable joints, and open joints are also common. Researchers compiled repair, maintenance, and re- placement procedures for all five joint types. The literature review identified a life-cycle cost analysis method, but its data requirements may make it imprac- tical for current usage. Additionally, survey respondents viewed life-cycle cost as a difficult-to-use performance measure, even if potentially valuable. Consequently, researchers proposed a flexible system for measuring perfor- mance based on joint opening, joint movement, skew, expected service life, installed cost, constructability, lead time, location, traffic, and durability. WHY IT MATTERS Preventing SMEJ failures will help avoid more serious damage to bridges, but doing so requires quality installation by trained crews. To help agencies maintain and replace SMEJs effectively, researchers developed a stand-alone document, Guidelines for Maintaining Small Movement Bridge Expansion Joints, which the AASHTO Subcommittee on Maintenance is currently reviewing for publication. In addition to illustrated repair and installation procedures, the guidelines include practices for evaluating joint condition and selecting replacement joints, formulas for calculating joint movement, a method for testing the watertightness of joints, and a simple procedure for calculating a benefit–cost ratio when comparing replacement joint options. NCHRP PROJECT 12-100 FINAL PRODUCTS Guidelines for Maintaining Small Movement Bridge Expansion Joints is under review for publication by the AASHTO Subcommittee on Maintenance. Contractor’s final report apps.trb.org/cmsfeed/TRBNetProject Display.asp?ProjectID=3651 NCHRP SENIOR PROGRAM OFFICER Waseem Dekelbab | wdekelbab@nas.edu PRINCIPAL INVESTIGATOR Tripp Shenton | shenton@udel.edu ADDITIONAL RESOURCES Simplifying Bridge Expansion Joint Design and Maintenance, South Carolina DOT report ntl.bts.gov/lib/46000/46200/46245/ SPR_677.pdf AASHTO Subcommittee on Maintenance, Bridges Technical Working Group maintenance.transportation.org July 2017 N C H R P R E A D Y R E S U L T S RESEARCH STRATEGY Investigators began by performing a comprehensive literature review and conducting surveys of bridge owners, bridge consultants, contractors, and SMEJ manufacturers. Using this information, the investigators determined the state of the practice in joint installation and maintenance, including the types of joints used, trends in joint usage, typical failure modes, and available maintenance guidelines. The surveys also included feedback on the effectiveness and ease of use of performance metrics for selecting replacement joints. RESOURCES The Transportation Research Board’s National Cooperative Highway Research Program (NCHRP) produces ready-to-implement solutions to the challenges facing transportation professionals. NCHRP is sponsored by the individual state departments of transportation of the American Association of State Highway and Transportation Officials (AASHTO), in cooperation with the Federal Highway Administration (FHWA). Any opinions and conclusions expressed or implied in resulting research products are those of the individuals and organizations who performed the research and are not necessarily those of TRB; the National Academies of Sciences, Engineering, and Medicine; or NCHRP sponsors. Im ag es o n th is pa ge fr om c on tra ct or ’s fin al re po rt TRANSPORTATION RESEARCH BOARD Step-by-step photos in the guidelines demonstrate the installation of several types of expansion joints, including this bonded joint seal.