Erosion and sediment control are necessary for environmental protection, water quality, and safety. Uncontrolled erosion and sediment runoff during highway construction may cause harmful impacts on receiving waters and habitats, drainage structures, and surrounding lands, and could be subject to public criticism and complaints. Best management practices (BMPs), which incorporate E&SC measures, are a set of procedures and controls installed at a construction site to help prevent soil erosion and reduce or eliminate water pollution and sedimentation problems during construction. These techniques also can minimize the need for contractors to take corrective actions during construction operations. To assist with E&SC practices, state DOTs have stormwater management programs (SWMPs), approaches, and guidelines that help address water quality degradation and minimize erosion and sediment runoff associated with highway construction activities. These SWMPs also guide the implementation of planning, construction, and proper installation and maintenance of BMPs as construction proceeds.

Although state DOTs have managed environmental and water quality issues associated with highway construction for years, information about the current state of the practice in construction stormwater management is needed to understand processes that work as well as existing challenges to managing stormwater permit and compliance requirements. In addition, gaps in knowledge and approaches can be identified for future research. Overall, a need exists to understand how state DOTs manage compliance with stormwater and environmental permit requirements for stormwater and E&SC for highway construction work.

Synthesis Objectives

The objectives of this synthesis are to investigate and document DOT practices, tools, and approaches for managing compliance with state and federal construction stormwater permit requirements. Specifically, this synthesis performs the following:

• Identifies the current state of the practice for managing construction stormwater programs, including BMPs and E&SC measures; tracking, monitoring, and reporting permit requirements; inspections and compliance; and other related aspects.
• Documents processes for preparing and managing SWPPPs from state DOTs.
• Reports qualifications and training information for designers and inspectors in the NPDES permitting program as well as the responsible parties for developing standards and specifications for stormwater management and E&SC practices.
• Documents the benefits and challenges of stormwater management for the construction of highways based on information provided by state DOTs.

Based on the objectives, the following areas were considered for data collection:

• Current practices, approaches, and processes used by state DOTs to manage, monitor, track, and record information for proper stormwater management during construction
• Types of BMPs and control measures used on DOT highway projects that are designed, installed, maintained, and inspected during construction
• Formal and informal tools, guidelines, and training that DOTs have in place for executing stormwater management according to specifications and permit requirements
• Information about the development and execution of the SWPPP for construction

Synthesis Approach

The literature review provided information about the current state of the practice for construction stormwater management, as well as the Clean Water Act (CWA), permits, BMPs, control measures, and inspections. Various reports, documents, manuals, journal articles, and websites

from state DOTs, the FHWA, and the EPA were consulted that address stormwater management and control measures for highway construction projects. The findings of the literature review are in Chapter 2.

A survey questionnaire was developed using the literature review and that follows the scope of work developed for this project. The survey questionnaire captured the state of the practice in construction stormwater program management. The survey was developed using the Qualtrics online survey platform and was electronically distributed to the AASHTO Committee on Construction voting members. This distribution included representatives from all 50 state DOTs and the Washington, DC, and Puerto Rico DOTs. The survey findings are presented in Chapter 3 based on 42 state DOT respondents (81% response rate). The survey questionnaire is presented in Appendix A. Individual state DOT survey question responses are provided in Appendix B.

Following the analysis of the survey responses, case example interviews were conducted to gather detailed information from DOTs about construction stormwater program management, SWPPPs, BMPs, and training. Initially, nine state DOTs were identified as candidates for case example interviews and were contacted. In total, six state DOTs participated: Colorado (AASHTO Region 4), Florida (AASHTO Region 2), Iowa (AASHTO Region 3), New York State (AASHTO Region 1), Pennsylvania (AASHTO Region 1), and Texas (AASHTO Regions 3/4). Details of the state DOT case example interviews are outlined in Chapter 4. The interview questions used for the case examples are provided in Appendix C.

Synthesis Organization

This synthesis includes five chapters.

• Chapter 1: Introduction to the subject area and description of the synthesis scope, objectives, and methodology
• Chapter 2: Literature review of the CWA, permitting, E&SC and BMPs, and inspections for stormwater management of highway construction
• Chapter 3: Current construction stormwater program management practices collected through the state DOT survey questionnaire
• Chapter 4: Case examples of construction stormwater management and associated factors conducted with six state DOTs (Colorado, Florida, Iowa, New York State, Pennsylvania, and Texas)
• Chapter 5: Key findings, current practices, and suggested future research to address knowledge gaps identified by the synthesis

The synthesis also includes the following sections:

• References: a list of sources cited within the synthesis
• List of Abbreviations and Acronyms used within the synthesis
• Appendix A: Survey Questionnaire
• Appendix B: Individual Survey Responses
• Appendix C: Case Examples Questionnaire
• Appendix D: Oklahoma DOT Clean Water Inspection Form
• Appendix E: West Virginia DOT Division of Highways Environmental Construction Inspection Form
• Appendix F: Colorado DOT Form 1176: Stormwater Field Inspection Report
• Appendix G: Florida DOT SWPPP Template
• Appendix H: Iowa DOT QA Inspection Form
• Appendix I: New York State DOT SPDES Stormwater Inspection Report Form
• Appendix J: Pennsylvania DOT Summary of Compliance Response Policy Table
• Appendix K: Texas DOT Form 2118: Field Inspection and Maintenance Report