Highway Hydraulic Engineering State of Practice (2020)

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35 Survey Summary How each state collects information is summarized in this chapter. A survey was sent via an electronic questionnaire to state hydraulic engineers of DOTs across the nation, including Puerto Rico and Washington, D.C. The survey was distributed in February 2019 and reminders were sent in March. Thirty-eight responses were received, for a 73% response rate. To assess updates to the state of practice, “10 years” was added to define the time frame during which the change occurred. At least one or more agencies responded yes in every category when asked, “Has your agency’s policy or guidance changed within the last 10 years” in regard to the topic. The data acquired included specific information relating to each topic by the carefully structured questions. The response “policy pending” was included as an answer choice so that the responder could indicate that a policy is being created. Although the pending policy was most likely not located during the literature review, this could be helpful so the reader can locate the policy in the future. The response “previously included” was included as an answer choice so that the responder could indicate that a policy exists but was not changed recently; the response “no” was intended to indicate that no policy exists, but in some cases it could also indicate that a policy exists but was not changed recently; a blank cell indicates no response. Question logic was used throughout the survey. Question logic presents the respondent with a general question, and if the condition was met or a response of “yes” or “previously included” was given, the reader was directed to one or more detailed questions about the same topic. If the condition was not met, or a “no” response was given, the survey skipped to the next general question pertaining to the topic (SurveyGizmo 2017). It should be noted that due to question logic, responding states may not have answered each question. An example of question logic used in the survey is as follows: A question in topic area 2, Roadway Drainage, is presented to the reader as follows: “c. Has your agency’s policy/guidance or the policy/guidance your agency follows changed within the last 10 years to include spread calculations for temporary construction?” If the response is “yes” or “previously included,” the respondent is directed to the following question: “d. Do the limits for temporary construction differ from permanent max allowable spread?” If the response is “no,” the respondent is directed to the next survey section as there are no more questions in the Roadway Drainage section. Two previous studies were referenced when developing the survey questions, although each of these studies had a different scope than the analysis herein. The FHWA Highway Hydraulics State of Practice Report (FHWA 2012a), which included an extensive survey, was referenced when developing the advanced hydraulic modeling questions in this survey. In addition, the Synthesis of Hydrologic and Hydraulic Impacts: Technical Report (University of Texas, San Antonio 2012) was referenced when developing this survey with focus on floodplain management. C H A P T E R 3 Survey Questionnaire

36 Highway Hydraulic Engineering State of Practice In addition to reporting statistics on responses, regional observations were investigated for apparent trends using the EPA Standard Federal Regions (chosen as most appropriate regional divisions in a geographical context), as shown in Figure 10 (EPA 2018). Regional trends in spe- cific subject areas are discussed later in this chapter, and a complete list of regional observations is included in Appendix B. The entities in each EPA Standard Federal Region are shown below. Those in parentheses did not provide a response to the survey questionnaire. Region 1: Connecticut, New Hampshire, Maine, Rhode Island, Vermont, (Massachusetts) Region 2: New York, (Puerto Rico, New Jersey) Region 3: Delaware, Maryland, Pennsylvania, Virginia, West Virginia, (D.C.) Region 4: Georgia, North Carolina, Tennessee, (Alabama, Florida, Kentucky, Mississippi, South Carolina) Region 5: Illinois, Indiana, Michigan, Minnesota, Ohio, Wisconsin Region 6: Arkansas, New Mexico, Oklahoma, Texas, (Louisiana) Region 7: Iowa, Missouri, Nebraska, (Kansas) Region 8: Colorado, Montana, North Dakota, South Dakota, Utah, Wyoming Region 9: California, Hawaii, (Arizona, Nevada) Region 10: Alaska, Oregon, Washington, (Idaho) Roadway Drainage Of the 38 states that responded, 13 (34%) indicated that their hydraulic policy or guidance changed within the past 10 years with respect to maximum allowable spread in travel lanes and/or the design event frequency for permanent/final designs. Only three states, North Carolina, Utah, and Wisconsin, indicated a change to include spread calculations for temporary construction, Figure 10. EPA Standard Federal Regions (EPA 2018).

Survey Questionnaire 37 with Wisconsin having a policy pending. North Carolina, Utah, and Washington State each have different limits for temporary construction and permanent maximum allowable spread. Shown in Figure 11 are percentages of those states that changed policies with respect to reduced inlet efficiency to account for debris build up. Twenty states responded regarding inlets, and 19 states responded regarding pipe culverts/headwalls (Table 2). In Region 5, Minnesota, Wisconsin, and Michigan previously included policies for the design of reduced inlet efficiency, and all West Coast states (not including Alaska) reported a policy change for inlets. Most states within Region 8 indicated a policy change regarding Maximum Allowable Spread. Culvert Aquatic Organism Passage Of the 38 states that responded, 17 (45%) have noted changes made in the last 10 years to include coordination with regulatory agencies for assistance in identifying aquatic organism passage and habitats (Table 3). In addition, 9 (24%) noted some changes made previously, while two states (5%) have policies pending. Regarding changes to include sensitive aquatic organism passage and habitats in culvert reha- bilitation, 11 (29%) denoted changes in the last 10 years, three (8%) mentioned previous changes, and four (11%) have policies pending. Of the 28 states that gave sources of information for changes in practices to include sen- sitive aquatic organism passage and habitats for culvert rehabilitation, 12 (41%) use a state hydraulics manual, 15 (54%) use FHWA HEC-26, 3 (11%) use USDA USFS Stream Simulation, 17 (61%) use HDS 5, and 9 (32%) use another source (Table 4). New Mexico Yes No Oregon Previously Included N/A Pennsylvania Previously Included Previously Included South Dakota Yes No Tennessee Previously Included Previously Included Texas Previously Included No Utah Yes Yes Virginia Yes No Washington Previously Included Previously Included Wisconsin Previously Included No State Inlets Pipe Culverts/Headwalls Alaska No Previously Included California Previously Included Previously Included Colorado Yes No Delaware Previously Included No Indiana Yes No Michigan Previously Included No Minnesota Previously Included No Missouri Previously Included No North Carolina Previously Included No Nebraska Previously Included Previously Included Table 2. Summary of responses: states that introduced a policy to include design for reduced inlet efficiency for inlets and pipe culverts/headwalls.

38 Highway Hydraulic Engineering State of Practice Of the 28 states that gave sources of information for changes in practices to include sensitive aquatic organism passage and habitats for culvert replacement, 18 (64%) use a state hydraulics manual, 20 (71%) use FHWA HEC-26, 8 (29%) use USDA USFS Stream Simulation, 20 (71%) use HDS 5, and 12 (43%) use another source (Table 5). Shown in Figure 12 are percentages of those states responding to the survey who changed poli- cies to include coordination with regulatory agencies or to include aquatic organism passage in culvert rehabilitation or replacement. The number of responses for each is as follows: Coordina- tion with regulatory agencies: 32; Rehabilitation: 29; Replacement: 29. Of the 28 states responding, 11 (39%) provided details on their sources for aquatic organism passage and habitats (Table 6). In Region 3, all states indicated a change in rehabilitation or replacement practice to include aquatic organism passage. Bridge Scour Computations and Countermeasures Of the 38 states that responded, 20 (53%) reported a change to either their scour calculation method or their scour countermeasure selection or design method (Table 7). Reasons for the changes include lack of data, uncertainties in rock characteristics and sediment size to input into scour equations, suspected over-prediction of scour, countermeasure failure, and uncertainty dealing with cohesive soils. Of the 19 states that responded regarding their scour countermeasure design methods, 1 (5%) uses USGS, 14 (74%) report using FHWA HEC-23, 2 (11%) use USACE, four (21%) use ASCE, three (16%) use USBR, one (5%) uses Isbash, five (26%) use Caltrans, and four (21%) use another method (Table 8). 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Policy change for inlets Policy change for pipe culverts/headwalls Yes No Previously Figure 11. States that introduced a policy change with regard to reduced inlet efficiency for inlets and pipe culverts/headwalls.

Survey Questionnaire 39 State Coordination with Regulatory Agencies Change in Rehabilitation Practice to Include Aquatic Organism Passage Change in Replacement Practice to Include Aquatic Organism Passage Alaska Previously Included Previously Included Previously Included Arkansas No No No California Previously Included Previously Included Previously Included Connecticut Yes No No Delaware Yes Yes Yes Georgia Yes No Yes Iowa Yes No Yes Illinois Yes No Yes Maryland Yes Policy Pending Policy Pending Maine Yes Yes Yes Michigan Previously Included No Previously Included Minnesota Previously Included Yes Yes Missouri No No Yes Montana Previously Included No Yes North Carolina Previously Included Policy Pending Previously Included North Dakota Yes Yes Yes Nebraska Previously Included No No New Hampshire Yes Yes Yes New York Yes Yes Yes Oklahoma Yes No No Oregon Yes Previously Included Previously Included Pennsylvania Yes Yes Yes South Dakota No No Yes Tennessee Policy Pending Policy Pending Policy Pending Texas Yes No No Utah Yes Yes Yes Virginia Yes Yes Yes Washington Yes Yes Yes Wisconsin Policy Pending Policy Pending Policy Pending West Virginia Previously Included Yes Yes Wyoming Previously Included No Previously Included Table 3. States that made a change to include coordination with regulatory agencies or consideration of aquatic organism passage in rehabilitation or replacement of culverts.

40 Highway Hydraulic Engineering State of Practice Source State State Hydraulic Manual FHWA HEC-26 USDA USFS Stream Simulation HDS 5 Other Alaska X X X California X X Colorado X Connecticut Recommendations from regulatory agency (Fisheries) Delaware X X Maryland Presently, a case-by-case design as agreed upon with environmental agencies; future designs to be based on policy guidelines being developed by the Michigan DOT SHA/MDE Hydraulics Panel. Maine X X Michigan X Minnesota X Minnesota DOT AOP Manual (published 2019), technical assistance from Minnesota DNR, and DNR general permit North Carolina X X North Dakota X Nebraska X X X New Hampshire X X New York X X X Ohio X X Oklahoma X X Oregon X X Hydraulic Method and/or Stream Simulation Pennsylvania X Publication 13M (DM-2) Rhode Island X X South Dakota X X X Tennessee X Texas X X X Utah X Virginia X X Culvert countersinking (prescriptive regulatory requirements) Vermont X Vermont ANR Guidance, not strictly followed Wisconsin X HEC-RAS culvert and channel velocity evaluation West Virginia X X Wyoming FishXing Table 4. Sources of information used for practices for sensitive aquatic organism passage and habitats for culvert rehabilitation.

Survey Questionnaire 41 State State Hydraulic Manual FHWA HEC-26 USDA USFS Stream Simulation HDS 5 Other Alaska X X X X California X X X X Connecticut X X X X X Delaware X X Georgia X X X X Hawaii X X Iowa X X Illinois X Maryland X Michigan X X Minnesota X X Missouri X Montana X North Carolina X X North Dakota X Nebraska X X X New Hampshire X X X New Mexico New York X X X Ohio X X Oklahoma X X Oregon X X X X Pennsylvania X X Rhode Island X X X X X South Dakota X X X Tennessee X Texas X X X Utah X Virginia X X X Vermont X X Washington X X Wisconsin X X X West Virginia X X X X Wyoming X Table 5. Sources of information used for practices for sensitive aquatic organism passage and habitats for culvert replacement.

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Coordination with Regulatory Agencies Change in Rehabilitation Practice to Include Aquatic Organism Passage Change in Replacement Practice to Include Aquatic Organism Passage Yes Previously IncludedNo Policy Pending Figure 12. States that made a change in dealing with regulatory agencies, rehabilitation, or replacement regarding aquatic organism passage in culverts. State Design Method URL Connecticut Recommendations from regulatory agency (Fisheries) Maryland 1. Presently, a case-by-case design as agreed upon with environmental agencies; 2. Future designs to be based on policy guidelines being developed by the Michigan DOT SHA/MDE Hydraulics Panel. http://gishydro.eng.umd.edu/hydrauli cs_panel.htm Minnesota Minnesota DOT AOP Manual (published 2019), technical assistance from Minnesota DNR, and DNR general permit http://www.dot.state.mn.us/research /reports/2019/201902.pdf New Hampshire https://www.des.nh.gov/organization /divisions/water/wetlands/streams_cr ossings.htm Oregon Hydraulic Method and/or Stream Simulation Pennsylvania Publication 13M (DM-2) http://www.dot.state.pa.us/public/pu bsforms/Publications/PUB%2013M/Se ptember%202018%20Change%20No. %203.pdf Virginia Culvert countersinking (prescriptive regulatory requirements) http://www.virginiadot.org/business/r esources/LocDes/DrainageManual/dra in-manual-chapter-08.pdf Vermont Vermont ANR Guidance, not strictly followed https://vtfishandwildlife.com/conserv e/aquatic-habitat- conservation/aquatic-organism- passage-at-road-stream-crossings Washington https://wdfw.wa.gov/sites/default/file s/publications/01501/wdfw01501.pdf Wisconsin HEC-RAS culvert and channel velocity evaluation Wyoming FishXing https://www.fs.fed.us/biology/nsaec/f ishxing/ Table 6. Sources of information for aquatic organism passage in culverts.

State Comp Method Change? Scour Countermeasure Change? California Yes Yes Colorado Yes Yes Delaware Yes Yes Iowa Yes Yes Illinois Yes Yes Indiana Yes No Maryland Yes Yes Maine No Yes Montana Yes Yes North Dakota No Yes New Hampshire Yes Yes New Mexico Yes No New York Yes Yes Oregon Yes Yes Pennsylvania Yes Yes Texas Yes Yes Utah Yes Yes Virginia Yes Yes Wisconsin Yes Yes West Virginia Yes No Table 7. States that made a change to either bridge scour calculation method or countermeasure selection Scour Countermeasure State FHWA HEC-23 USACE ASCE USBR USGS Isbash Caltrans Other Alaska X X Arkansas X California X Delaware X Georgia X Iowa X Iowa DOT Indiana X Maryland X X ABSCOUR 10 Maine X Nebraska X X New Mexico X X New York X Oklahoma X X Proven maintenance methods Pennsylvania X Publication 15M (DM-4)* Rhode Island X X South Dakota X Tennessee X X X X Texas X Washington X X X *Note: Publication 15M (DM-4): https://www.dot.state.pa.us/public/PubsForms/Publications/PUB%2015M.pdf Table 8. Bridge scour countermeasure methods employed by each state.

44 Highway Hydraulic Engineering State of Practice Four states shared information regarding scour countermeasure design (Table 9). In Region 3, all states indicated a change in their policy regarding scour computations in the past decade. In contrast, no states in Region 4 reported policy changes for bridge scour computa- tions or countermeasures. Advanced Hydraulic Modeling Of the 38 states that responded to the question regarding policy or guidance change within the last 10 years to use unsteady flow modeling for some projects, 21 (55%) replied “some” or “few” projects for 2D unsteady flow for bridge design, one (3%) replied “few” for 3D unsteady flow for bridge design, 16 (42%) replied “some” or “few” for 2D unsteady flow for culvert design, and one (3%) replied “few” for 3D unsteady flow for culvert design. For other methods, when asked to list the agency’s preferred design method for advanced hydraulic modeling, two states (5%) use 2D steady flow for bridge design and one (3%) specified use of SRH-2D. (Table 10). In the 2012 FHWA Highway Hydraulics State of Practices Report (FHWA Resource Center Hydraulics Technical Service Team 2012), 33 out of 51 respondents reported routinely or occasionally using 2D steady flow models for bridge design, 15 out of 50 respondents reported routinely or occasionally using 2D unsteady flow models for bridge design, and four reported routinely or occasionally using 3D steady/unsteady flow models. A similar question was not asked pertaining to culvert modeling. No states responding from Regions 5 or 9 require unsteady flow modeling for projects. In Regions 3, 4, 7, 8, and 10, no states reported sediment transport models being implemented within the last ten years. Shown in Figure 13 are percentages of those states that indicated using advanced hydraulic modeling methods. The number of responses for each model type are as follows: 2D unsteady— bridge design: 26; 3D unsteady—bridge design: 24; 2D unsteady—culvert design: 25; 3D unsteady—culvert design: 24. Regulatory Requirements Of the 38 states that responded to changing policy or guidance in the past 10 years regarding state oversight for FHWA National Environmental Policy Act (NEPA), eight (21%) reported a change, eight (21%) reported no change, and 21 (55%) indicated they have programmatic agreements. Of the 38 states that responded to changing policy or guidance in the past 10 years regarding Section 404 of the Clean Water Act (CWA), 11 (29%) reported a change, 14 (37%) reported no change, and 11 (29%) said they have programmatic agreements. State Countermeasure Design Iowa https://iowadot.gov/bridge/policy/03-02-02PrelimC.pdf Maryland http://gishydro.eng.umd.edu/sha_soft.htm Oklahoma https://www.ok.gov/odot/Doing_Business/Pre- Construction_Design/Bridge_Design/Hydraulics_Operations/ Pennsylvania http://www.dot.state.pa.us/public/PubsForms/Publications/PUB%2015M.pdf Table 9. Bridge scour countermeasure design methods shared by select states.

State c. Other Alaska No Some None Some None Arkansas No Few None Few None California No Few None Few None Colorado No Some None Some None Connecticut No Few None Few None Delaware No Some None Some None Georgia No Some None Few None Iowa No Few None Some None 2D Steady Bridge Design Illinois No Few None None None Maryland Yes Few Few Maine None None None None SRH-2D Michigan No None None None None Minnesota No Few None None None Montana No None None None None 2D Steady Bridge Design North Carolina Policy Pending Few None None None Nebraska Yes Most studies None Few None New Hampshire Previously Required Some Few Few Few New Mexico Policy Pending Some None None None New York Yes Few a. Has your agency's policy or guidance changed within the last 10 years to require unsteady flow modeling for some projects? b. What methods are used? 2D unsteady – bridge design: b. What methods are used? 3D unsteady – bridge design: b. What methods are used? 2D unsteady – culvert design: b. What methods are used? 3D unsteady – culvert design: Oregon No Few None Few None South Dakota Yes None None None None Tennessee Policy Pending Some None Some None Texas Yes Few None Few None Utah Yes Some None Few None Vermont Some None None None Washington Yes Some None Some None Table 10. States that have changed their advanced hydraulic modeling policy for, or report use of, 2D or 3D hydraulic modeling. 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 2D unsteady – bridge design: 3D unsteady – bridge design: 2D unsteady – culvert design: 3D unsteady – culvert design: Most Some Few None Figure 13. States that indicated using advanced hydraulic modeling methods.

46 Highway Hydraulic Engineering State of Practice Of the 38 states that responded to changing policy or guidance in the past 10 years to comply with local floodplain requirements, 11 (29%) reported a change, 17 (47%) reported no change, eight (21%) said they have programmatic agreements. Of the 38 states that responded to changing policy or guidance in the past 10 years regarding requiring the National Pollutant Discharge Elimination System (NPDES), 18 (47%) said “yes,” nine (24%) said “no,” and nine (24%) said they have programmatic agreements. Of the 38 states that responded to changing policy or guidance in the past 10 years regarding requiring LID, 13 (34%) said “yes,” 20 (53%) said “no,” and four (11%) said they have program- matic agreements. Individual state responses are found in Table 11. Georgia No Yes No Yes Yes Hawaii No Yes No No Yes Iowa Has Programmatic Agreement No Yes Yes Yes Illinois Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Indiana No Maryland No No Yes No Yes Maine No No No No No Michigan Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Programmatic Agreement Pending No Minnesota Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Missouri Has Programmatic Agreement Has Programmatic Agreement No Has Programmatic Agreement No State State oversight for FHWA National Environmental Policy Act (NEPA): Clean Water Act (CWA) Section 404: To comply with local floodplain requirements: Requirements for National Pollutant Discharge Elimination System (NPDES): Requirements for Low Impact Development (LID) (e.g., bioretention, permeable pavement, etc.): Alaska Has Programmatic Agreement Programmatic Agreement Pending Yes Yes No Arkansas No No No No No California Has Programmatic Agreement No No Yes No Colorado No No Yes Yes No Connecticut Has Programmatic Agreement No Yes Yes Yes Delaware Yes Yes Yes Yes Yes Table 11. State responses to programmatic agreement questions: Agency’s policy or guidance changed within the last 10 years (to include):

Survey Questionnaire 47 Vermont No No No No No Washington Yes Yes Yes Yes Yes West Virginia Has Programmatic Agreement Has Programmatic Agreement No Yes No Wyoming Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement No Oklahoma Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Oregon No No No No No Pennsylvania Yes Yes Yes Yes Yes Rhode Island Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement South Dakota Has Programmatic Agreement Yes No No No Tennessee Yes Yes No Yes No Texas Has Programmatic Agreement Yes No Has Programmatic Agreement No Utah Yes Yes Yes Yes Yes Agreement Agreement Virginia Has Programmatic Has Programmatic No Yes Yes State State oversight for FHWA National Environmental Policy Act (NEPA): Clean Water Act (CWA) Section 404: To comply with local floodplain requirements: Requirements for National Pollutant Discharge Elimination System (NPDES): Requirements for Low Impact Development (LID) (e.g., bioretention, permeable pavement, etc.): North Carolina Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement North Dakota Has Programmatic Agreement Yes Yes No No Wisconsin Has Programmatic Agreement No No No No Montana Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Has Programmatic Agreement Yes Nebraska Yes No No Yes No New Hampshire Has Programmatic Agreement No No Yes No New Mexico Has Programmatic Agreement No No Yes Yes New York Yes Yes Yes Yes No Ohio Yes No Yes Yes Yes Table 11. (Continued).

48 Highway Hydraulic Engineering State of Practice Shown in Figure 14 are percentages of states responding (N = 37) that changed policies with respect to state oversight of the NEPA, CWA Section 404, compliance with local floodplain requirements, requirements for the NPDES, and requirements for LID (e.g., bioretention, per- meable pavement). Floodplain Impacts and Mitigation Of the 24 states that responded to changing policy or guidance for floodplain impacts within the last 10 years, four (17%) reported a change with respect to design flood frequency, two (8%) have a policy pending, and 18 (75%) indicated either no change or that they are following previous policy or guidance. In regard to mitigation, three (12.5%) reported policy or guidance change, three (12.5%) have policy pending, and 18 (75%) indicated no change or following previous policy/guidance. For no adverse impact/zero rise, three (12.5%) reported a change, two (8%) have policy pending, and 19 (79%) indicated no change or following previous policy/ guidance. Results are summarized in Table 12. When asked what is included in the “no adverse impact or zero rise” policy or guidance, all 21 responders indicated that water surface elevation matching is included. Approximately half of the states (11, or 52%) indicated they also include peak flow matching, while only 4 (19%) include volumetric matching. In addition, 10 (48%) of the states responding indicated inclusion of tolerance levels, while no states reported having different policy requirements for unsteady flow modeling. Two states (8%) reported including requirements other than those mentioned in the survey. Results are summarized in Table 13. Shown in Figure 15 are percentages of the responding states (N = 24) that changed policies with respect to flood frequency, mitigation, and no adverse impact/zero rise. Shown in Figure 16 are percentages of the responding states (N = 21) where policy includes peak flow matching, volumetric matching, water surface elevation matching, tolerance levels, 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% State oversight for FHWA National Environmental Policy Act (NEPA): Clean Water Act (CWA) Section 404: To comply with local floodplain requirements: Requirements for National Pollutant Discharge Elimination System (NPDES): Requirements for Low Impact Development (LID) (e.g. bioretention, permeable pavement, etc.): Has Programmatic Agreement Programmatic Agreement Pending Yes No Figure 14. Regulatory requirements.

State Flood Frequency Mitigation No Adverse Impact/Zero Rise Alaska Yes No Yes California Previously included Previously included No Colorado Previously included Yes Yes Connecticut No Policy Pending Policy Pending Delaware Policy Pending Policy Pending No Iowa Yes No No Illinois Previously included No Previously included Michigan Previously included No Previously included Minnesota Previously included Previously included Previously included Missouri Previously included Previously included Previously included Montana Previously included No Policy Pending North Carolina Policy Pending Policy Pending Previously included New Mexico Previously included Previously included Previously included New York Yes Yes No Ohio No No Yes Oklahoma Previously included Previously included Previously included Oregon Previously included Previously included Previously included Pennsylvania Yes Yes Previously included Rhode Island Previously included Previously included Previously included Tennessee Previously included Previously included Previously included Utah Previously included No Previously included Virginia Previously included Previously included Previously included West Virginia Previously included Previously included Previously included Wyoming Previously included Previously included Previously included Table 12. States that made a change in floodplain impact policy/guidance. State Peak Flow Matching Volumetric Matching Water Surface Elevation Matching Tolerance Levels Different Policy Requirements for Unsteady Flow Other Alaska Yes No Yes No No Colorado Yes No Yes Yes No Yes Connecticut No Yes Yes Yes No No Illinois Yes No Yes No No No Michigan Yes No Yes Yes No No Minnesota No No Yes Yes No Yes Missouri No No Yes No No Montana Yes No Yes Yes No North Carolina Yes No Yes Yes No No New Mexico No No Yes Yes No New York Yes Yes Yes Ohio Yes Oklahoma Yes Yes Yes No No No Oregon No No Yes Yes No No Pennsylvania Yes Yes Yes No No No Rhode Island Yes Yes Yes Tennessee No No Yes No No No Utah Yes Virginia No No Yes No No No West Virginia No No Yes Yes No Wyoming Yes No Yes No No No Table 13. What is included in the “no adverse impact or zero rise” policy or guidance.

50 Highway Hydraulic Engineering State of Practice 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Flood Frequency Mitigation No Adverse Impact/Zero Rise Yes No Previously Included Policy Pending Figure 15. States that made a change in floodplain impact policy guidance. 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Peak Flow Matching Volumetric Matching Water Surface Elevation Matching Tolerance Levels Different Policy Requirements for Unsteady Flow Other Yes No N/A Figure 16. What is included in the “no adverse impact or zero rise” policy or guidance?

Survey Questionnaire 51 different policy requirements for unsteady flow, and other requirements in policies/guidance for zero rise or no adverse impact. Coastal Hydraulics Of the 38 states responding to the survey, 14 represented coastal states (excluding the Great Lakes region), and eight (57%) of these indicated that they have policies or procedures address- ing coastal hydraulics. With respect to the specific coastal protection measures addressed in the survey, two states (North Carolina, Oregon) currently address structure hydraulic response to waves; three (North Carolina, New Hampshire, Oregon) address armor protection loading response; one (Oregon) addresses foundation soil loads; and four (North Carolina, New Hamp- shire, New York, Oregon) address scour protection. Only New York reported that its policy or guidance for scour protection has changed in last 10 years. No states reported having measures in duplicate as redundant protection measures. However, Texas reports a policy pending to address redundant protection measures. Texas is also the one state with a coastal hydraulics policy pending. Five states (California, New Hampshire, New York, North Carolina, Texas) reported current or pending policy or guidance on design practices for flood protection of roadways from erosion due to waves or changes in water surface elevation. Specifically: • California reports that its policy or guidance for revetments has changed in the last 10 years; • New Hampshire reports that its policy or guidance for green or gray capture/filter/protection infrastructure for protection of roadways from erosion has changed in the last 10 years. New Hampshire also reports having previous policy or guidance on landscaped berms, flood/sea walls, revetments, and freeboard requirements; • New York reports that its policies or guidance for the following have changed in the last 10 years: landscape berms, flood closures, flood/sea walls, revetments, hardened dunes, green- way corridors/buffer areas, green/gray capture/filter/protection, freeboard and setback require- ments, more durable materials, and alternate alignments away from the coast; • North Carolina reports policy pending for freeboard requirements; • Texas reports policies pending for landscape berms, revetments, greenway corridors/buffer areas, freeboard requirements, more durable materials, and alternate alignments away from the coast, as well as measures in duplicate as redundant protection measures. Texas also has guidance pending on sea level rise, with publication currently planned for September 2019. These responses are summarized in the Table 14. State Structure Hydraulic Response to Waves Armor Protection Loading Response Foundation Soil Loads Scour Protection Revetments Vulnerability/ Other California Yes Yes North Carolina Previous Previous Previous Yes, Previous, Pending New Hampshire Previous Previous Previous New York Yes Yes Yes Oregon Previous Previous Previous Previous Texas Pending Pending Pending Pending Pending Pending Table 14. Reported changes in policy or guidance to include engineering response to coastal hazards.

52 Highway Hydraulic Engineering State of Practice Alternative Project Delivery Methods Of the 21 states that responded to changing policy or guidance within the last 10 years to include prescriptive alternative delivery policy for hydraulic aspects of projects, five (24%) reported new policy or guidance, four (19%) reported that policy or guidance previously included these, two (10%) have policy pending, and 10 (48%) indicated they did not change their policy or guidance to include these. Of the 21 states that responded to changing policy or guidance within the last 10 years to include RFQ language for hydraulic aspects of alternatively delivered projects, nine (43%) reported a change, three (14%) reported previous policy or guidance, two (10%) have policy pending, while seven (33%) indicated no change. Of the 21 states that responded to changing policy or guidance within the last 10 years to include RFP language for hydraulic aspects of alternatively delivered projects, 12 (57%) reported a change, 3 (14%) previously included these, three (14%) have policy pending, and three (14%) indicated no change. Table 15 summarizes these results. a. Has your agency's policy or guidance changed within the last 10 years to include? i. Prescriptive alternative delivery policy for hydraulic aspects of projects: ii. Standard request for qualifications (RFQ) language for hydraulic aspects of alternatively delivered projects: iii. Standard request for proposal (RFP) language for hydraulic aspects of …: Alaska No No Policy pending Colorado No No No Connecticut Policy pending Policy pending Policy pending Delaware No No Yes Georgia No Yes Yes Iowa No No Yes Indiana Yes Yes Yes Minnesota Previously included Previously included Previously included Montana No Yes Yes North Carolina No No No New Hampshire No No Yes New York Yes Yes Yes Ohio Yes Yes Yes Oregon Policy pending Policy pending Policy pending Pennsylvania Yes Yes Yes Rhode Island Previously included Previously included Previously included Tennessee No No No Texas Previously included Previously included Previously included Utah Yes Yes Yes Washington Previously included Yes Yes West Virginia No Yes Yes Table 15. States that made a change to include alternative project delivery methods.

Survey Questionnaire 53 When asked about documentation of alternative delivery policy or guidance that includes provisions for hydraulic design, six states (29%) replied that provisions for hydraulic policy are combined in an alternative delivery project manual, and another six states (29%) reported that provisions for hydraulic policy are in a RFP template. No states replied that they had a separate hydraulic alternative delivery project manual or that the alternative delivery policy was docu- mented in the agency’s hydraulics manual, while eight states responded with “Other.” Table 16 summarizes these results. If a state responded “Other,” the location of the policy or guidance may be listed in Table 17. In addition, 12 states (57%) provided responses regarding the type of alternative project deliv- ery methods used and the location of provisions for hydraulic design. Table 17 outlines indi- vidual state responses. Shown in Figure 17 are percentages of those states who changed policies to include prescrip- tive alternative delivery policy for hydraulic aspects of projects, standard RFQ language for hydraulic aspects of alternatively delivered projects, or standard RFP language for hydraulic aspects of projects. Additionally, states were asked where the alternative delivery policy or guid- ance that includes provisions for hydraulic design is documented. Responses were that hydraulic policy is combined in an alternative delivery project delivery manual, or else it is included in the request for proposal template. No states reported a separate alternative delivery hydraulic policy manual. Hydraulic policy combined in alternative delivery project delivery manual Request for proposal template Other Colorado Yes No No Connecticut No No Yes Georgia No Yes No Indiana Yes No No Maryland No No Yes Maine No No Yes Minnesota Yes No No Missouri No Yes No North Carolina Yes Yes No New Hampshire No No Yes Ohio No No Yes Pennsylvania No No Yes Tennessee Yes No No Texas No Yes No Utah No Yes No Washington Yes Yes Yes West Virginia No No Yes Table 16. Location of the alternative delivery policy or guidance that includes provisions for hydraulic design location.

54 Highway Hydraulic Engineering State of Practice 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Yes No Previously Included Policy Pending N/A Figure 17. Alternative delivery policy for hydraulic aspects of projects. When asked to list the agency's design method for alternative delivery policy or guidance and the URL where it can be accessed, the following provided responses: Connecticut To be determined (work in progress) Indiana Technical provisions Maryland Case-by-case project specs Maine Design-Build https://www.maine.gov/mdot/cpo/apdm/#apdm1 Minnesota Design-Build Manual Section 4 RFQ/RFP and RFP template Book 2 Section 12 for drainage http://www.dot.state.mn.us/designbuild/resources.html North Carolina Design-Build process https://connect.ncdot.gov/letting/Pages/Design-Build-Resources.aspx New Hampshire https://www.nh.gov/dot/org/projectdevelopment/bridgedesign/manual.htm Ohio Specific for the project and the delivery type. http://www.dot.state.oh.us/Divisions/ConstructionMgt/design- build/Pages/Design_Build.aspx Pennsylvania Alternate delivery still followed all applicable Pennsylvania DOT publications Tennessee Hydraulic design is same whether traditional or alternative project delivery. https://www.tn.gov/tdot/tdot-construction-division/transportation- construction-alternative-contracting.html Utah Design-Build https://www.udot.utah.gov/main/f?p=100:pg:0:::1:T,V:4552,72396 Washington http://www.wsdot.wa.gov/Projects/delivery/designbuild/PDMSG.htm Table 17. Type and location of alternative project delivery methods with provisions of hydraulic design.