Common use of Drainage Report Clause in Contracts

Drainage Report. 1. The Engineer shall prepare a single comprehensive drainage study and report of the project area. The report shall be divided into two (2) phases: a. Obtain existing HEC-2 or HEC-RAS models from applicable drainage authorities to the extent possible, for use in analysis and determination of the existing 2, 5, 10, 25, 50, 100 and 500 year (if available), water surface elevations at bayous, creeks, and ditch crossings along the project. This data will be utilized in the development of design roadway profiles. b. Profile of natural ground along each proposed grade line of the roadway. c. Profile of tentative proposed grade line of the roadway. d. Profile of existing roadway. e. Identify the existing drainage outfalls. f. Identify the names of existing creeks, bayous and ditches within the project limits. 2. These profiles shall be superimposed on a drawing along with the 2, 5, 10, 25, 50, 100 and 500 year (if available) water surface elevations. The profile drawing will provide an overall view of the roadway/existing ground elevations with respect to the various storm design frequencies for the length of the project. This will enable the State to determine the most feasible proposed roadway profile. These profiles must be submitted to the State and approved before continuing with the preparation of the comprehensive drainage report. NOTE: THE ENGINEER SHALL COORDINATE WITH ALL GOVERNMENT AGENCIES THROUGH THE STATE’S DISTRICT OFFICE. a. Manhole head losses shall be computed as per the State’s direction. Also, THYSYS (WINSTORM) computations are not needed for hydraulic grade line investigations. The head losses shall be computed with a pressure flow equation generally applicable to pipe running full flow. A hydraulic grade line starting at the outfall channel will be determined for each storm sewer system in order to obtain a design tailwater for each existing system. The design tailwater shall be the starting basis for the design of the proposed storm sewer system. b. For drainage areas, the Engineer shall limit the outfalls into existing storm sewer to existing capacity flows, which will be determined by the Engineer. Alternate flow routes, if feasible, shall be looked into for relieving storm sewer overload. The amount of the total detention storage to control storm sewer runoff for the design frequency shall be determined based on hydrograph routing, as well as a rough estimate of the available on-site volume. c. Drainage areas and flows for cross culvert drainage systems shall be determined as part of the comprehensive drainage report. Once determined, the sizing of the drainage crossings, hydrologic and hydraulics information will be provided to the State. DocuSign Envelope ID: 6D01D1D9-6E7F-481D-80FF-D7092F6A0AEE d. The Engineer shall prepare a report signed, sealed and dated by a registered/licensed engineer and shall include the preliminary findings of the storm sewer capacities, requirement for line rerouting, preliminary detention storage volumes based on hydrograph and initial recommendations on how to mitigate the storm impact on the receiving streams. The report shall also include preliminary sizing of the trunk line for the proposed gravity storm sewer within the limits of the project, conceptual and generic discussions of the alternatives considered, a comparative cost associated with each alternative and a recommended solution. e. Recommendations at this point should be generic and conceptual in nature, mainly for discussions with the State and the local government entities. An impact analysis is required on bayous, creeks and ditches as related to the State and FEMA criteria 10 and 100 year storm. The State’s required approach for impact prediction is as follows: a. Drainage areas for the existing and proposed conditions. b. Identify the existing drainage outfalls. c. Compute right of way corridor 100 year flood plain volumes for existing and proposed roadway elevations. A decrease in 100 year flood plain volumes is not allowed by the State or other governmental agencies, without adequate offsite mitigation. d. Compute existing and proposed peak flows by using hydraulics and hydrologic methodology and computer models. The additional lanes should be accounted for by increasing percent development. e. Storage computations will be based on hydrograph calculations and peak flows obtained in the item above. A mitigation volume for the 100 year storm will be computed. f. Analyze existing and proposed drainage system and quantify the increase in 100 year peak flows resulting from the roadway improvements. g. Hand calculations shall be provided which quantify the cut and fill within the 100 year flood plain, if any occur. h. Prepare conceptual 100 year sheet flow analysis for project utilizing existing and proposed conditions. i. Obtain current hydrologic and hydraulic computer models from government agencies and review and comment on the models. j. Current models will be updated to existing condition using the available State aerial photographs, and submitted to governmental agencies as the revised existing condition model. k. Analyze proposed roadway and outfall drainage improvements to quantify impacts to revised existing condition model. This contract does not include the detailed design of outfall improvements outside of the right of way, except for ditch outfall transitions of cross drainage culvert structures to the existing ditch.

Drainage Report. 1. The Engineer shall prepare a single comprehensive drainage study and report of the project area. The report shall be divided into two (2) phases: a. :  Obtain existing HEC-2 or HEC-RAS models from applicable drainage authorities to the extent possible, for use in analysis and determination of the existing 2, 5, 10, 25, 50, 100 and 500 year (if available), water surface elevations at bayous, creeks, and ditch crossings along the project. This data will be utilized in the development of design roadway profiles. b. .  Profile of natural ground along each proposed grade line of the roadway. c. .  Profile of tentative proposed grade line of the roadway. d. .  Profile of existing roadway. e. .  Identify the existing drainage outfalls. f. .  Identify the names of existing creeks, bayous and ditches within the project limits. 2. These profiles shall will be superimposed on a drawing along with the 2, 5, 10, 25, 50, 100 and 500 year (if available) water surface elevations. The profile drawing will provide an overall view of the roadway/existing ground elevations with respect to the various storm design frequencies for the length of the project. This will enable the State to determine the most feasible proposed roadway profile. These profiles must be submitted to the State and approved before continuing with the preparation of the comprehensive drainage report. NOTE: THE ENGINEER SHALL COORDINATE WITH ALL GOVERNMENT AGENCIES THROUGH THE STATE’S DISTRICT OFFICE. a. .  Manhole head losses shall be computed as per the State’s direction. Also, THYSYS (WINSTORM) computations are not needed for hydraulic grade line investigations. The head losses shall will be computed with a pressure flow equation generally applicable to pipe running full flow. A hydraulic grade line starting at the outfall channel will be determined for each storm sewer system in order to obtain a design tailwater for each existing system. The design tailwater shall will be the starting basis for the design of the proposed storm sewer system. b. .  For drainage areas, the Engineer shall limit the outfalls into existing storm sewer to existing capacity flows, which will be determined by the Engineer. Alternate flow routes, if feasible, shall will be looked into for relieving storm sewer overload. The amount of the total detention storage to control storm sewer runoff for the design frequency shall will be determined based on hydrograph routing, as well as a rough estimate of the available on-site volume. c. .  Drainage areas and flows for cross culvert drainage systems shall will be determined as part of the comprehensive drainage report. Once determined, the sizing of the drainage crossings, hydrologic and hydraulics information will be provided to the State. DocuSign Envelope ID: 6D01D1D9-6E7F-481D-80FF-D7092F6A0AEE d.  The Engineer shall prepare a report signed, sealed and dated by a registered/licensed engineer and shall include the preliminary findings of the storm sewer capacities, requirement for line rerouting, preliminary detention storage volumes based on hydrograph and initial recommendations on how to mitigate the storm impact on the receiving streams. The report shall will DocuSign Envelope ID: A33CD0F3-7A97-41CC-9FAE-FCF24754E948 Contract No. 88-6IDP5100 PS Contract No. 4682 Supplemental Agreement No. 3 also include preliminary sizing of the trunk line trunkline for the proposed gravity storm sewer within the limits of the project, conceptual and generic discussions of the alternatives considered, a comparative cost associated with each alternative and a recommended solution. e. .  Recommendations at this point should be generic and conceptual in nature, mainly for discussions with the State and the local government entities. An impact analysis is required on bayous, creeks and ditches as related to the State and FEMA the Federal Emergency Management Agency (FEMA) criteria 10 and 100 year storm. The State’s State required approach for impact prediction is as follows: a. :  Drainage areas for the existing and proposed conditions. b. Identify .  The Engineer shall identify the existing drainage outfalls. c. .  Compute right of way corridor 100 year flood plain volumes for existing and proposed roadway elevations. A decrease in 100 year flood plain volumes is not allowed by the State or other governmental agencies, without adequate offsite mitigation. d. .  Compute existing and proposed peak flows by using hydraulics and hydrologic methodology and computer models. The additional lanes should be accounted for by increasing percent development. e. .  Storage computations will be based on hydrograph calculations and peak flows obtained in the item above. A mitigation volume for the 100 year storm will be computed. f. .  Analyze existing and proposed drainage system and quantify the increase in 100 year peak flows resulting from the roadway improvements. g. .  Hand calculations shall be provided which quantify the cut and fill within the 100 year flood plain, if any occur. h. .  Prepare conceptual 100 year sheet flow analysis for project utilizing existing and proposed conditions. i. .  Obtain current hydrologic and hydraulic computer models from government agencies and review and comment on the models. j. .  Current models will be updated to existing condition using the available State aerial photographs, and submitted to governmental agencies as the revised existing condition model. k. .  Analyze proposed roadway and outfall drainage improvements to quantify impacts to revised existing condition model. This contract does not include the detailed design of outfall improvements outside of the right of way, except for ditch outfall transitions of cross drainage culvert structures to the existing ditch.

Drainage Report. 1. The Engineer shall prepare a single comprehensive drainage study and report of the project area. The report shall be divided into two (2) phases: a. : WAs Used DocuSign Envelope ID: 56C9F445-711D-4155-8CAC-4A873A2298E4  Collect as-built drawings and complete field investigations  Obtain existing HEC-2 or HEC-RAS models from applicable drainage authorities to the extent possible, for use in analysis and determination of the existing 2, 5, 10, 25, 50, 100 and 500 year (if available)year, water surface elevations at bayous, creeks, and ditch crossings along the project. This data will be utilized in the development of design roadway profiles. b. .  Profile of natural ground along each proposed grade line of the roadway. c. .  Profile of tentative proposed grade line of the roadway. d. .  Profile of existing roadway. e. .  Identify the existing drainage outfalls. f. .  Identify the names of existing creeks, bayous bayous, ditches and ditches reservoirs within the project limits. 2. These profiles shall be superimposed on a drawing along with the 2, 5, 10, 25, 50, 100 and 500 year (if available) water surface elevations. The profile drawing will shall provide an overall view of the roadway/roadway and existing ground elevations with respect to the various storm design frequencies for the length of the project. This will shall enable the State to determine the most feasible proposed roadway profile. These profiles must be submitted to the State and approved before continuing with the preparation of the comprehensive drainage report. NOTE: THE ENGINEER SHALL COORDINATE WITH ALL GOVERNMENT AGENCIES THROUGH THE STATE’S DISTRICT OFFICE. a. Manhole head losses shall be computed as per the State’s direction. Also, THYSYS (WINSTORM) computations are not needed for hydraulic grade line investigations. The head losses shall be computed with a pressure flow equation generally applicable to pipe running full flow. A hydraulic grade line starting at the outfall channel will be determined for each storm sewer system in order to obtain a design tailwater for each existing system. The design tailwater shall be the starting basis for the design of the proposed storm sewer system. b. For drainage areas, the Engineer shall limit the outfalls into existing storm sewer to existing capacity flows, which will be determined by the Engineer. Alternate flow routes, if feasible, shall be looked into for relieving storm sewer overload. The amount of the total detention storage to control storm sewer runoff for the design frequency shall be determined based on hydrograph routing, as well as a rough estimate of the available on-site volume. c.  Drainage areas and flows for cross culvert drainage systems shall be determined as part of the comprehensive drainage report. Once determined, the sizing of the drainage crossings, hydrologic and hydraulics information will shall be provided to the State. DocuSign Envelope ID: 6D01D1D9-6E7F-481D-80FF-D7092F6A0AEE d.  The Engineer shall prepare a report signed, sealed and dated by a registered/licensed engineer and shall include the preliminary findings of the storm sewer cross culvert and ditch capacities, requirement for line rerouting, preliminary detention storage volumes based on hydrograph and initial recommendations on how to mitigate the storm impact on the receiving streams. The report shall also include preliminary sizing of the trunk line for the proposed gravity storm sewer within the limits of the project, conceptual and generic discussions of the alternatives considered, a comparative cost associated with each alternative and a recommended solution. e.  Recommendations at this point should shall be generic and conceptual in nature, mainly for discussions with the State and the local government entities. An impact analysis is required on bayous, creeks and ditches as related to the State and FEMA criteria 10 and 100 year storm. The State’s State required approach for impact prediction is as follows: a. :  Drainage areas for the existing and proposed conditions. b. Identify .  The Engineer shall identify the existing drainage outfalls. c. . WAs Used DocuSign Envelope ID: 56C9F445-711D-4155-8CAC-4A873A2298E4  Compute right of way corridor 100 year flood plain volumes for existing and proposed roadway elevations. A decrease in 100 year flood plain volumes is not allowed by the State or other governmental agencies, without adequate offsite mitigation. d. .  Compute existing and proposed peak flows by using hydraulics and hydrologic methodology and computer models. The additional lanes should be accounted for by increasing percent development. e. .  Storage computations will be based on hydrograph calculations and peak flows obtained in the item above. A mitigation volume for the 100 year storm will be computed. f. .  Analyze existing and proposed drainage system and quantify the increase in 100 year peak flows resulting from the roadway improvements. g. Hand calculations shall be provided which quantify the cut and fill within the 100 year flood plain, if any occur. h. .  Prepare conceptual 100 year sheet flow analysis for project utilizing existing and proposed conditions. i. .  Obtain current hydrologic and hydraulic computer models from government agencies and review and comment on the models. j. .  Current models will be updated to existing condition using the available State aerial photographs, and submitted to governmental agencies as the revised existing condition model. k. .  Analyze proposed roadway and outfall drainage improvements to quantify impacts to revised existing condition model. This contract does not include the detailed design of outfall improvements outside of the right of way, except for ditch outfall transitions of cross drainage culvert structures to the existing ditch.

Drainage Report. 1. The Engineer shall prepare a single comprehensive drainage study and report of the project area. The report shall be divided into two (2) phases: a. Obtain existing HEC-2 or HEC-RAS models from applicable drainage authorities to the extent possible, for use in analysis and determination of the existing 2, 5, 10, 25, 50, 100 and 500 year (if available), water surface elevations at bayous, creeks, and ditch crossings along the project. This data will be utilized in the development of design roadway profiles. b. Profile of natural ground along each proposed grade line of the roadway. c. Profile of tentative proposed grade line of the roadway. d. Profile of existing roadway. e. Identify the existing drainage outfalls. f. Identify the names of existing creeks, bayous and ditches within the project limits. 2. These profiles shall be superimposed on a drawing along with the 2, 5, 10, 25, 50, 100 and 500 year (if available) water surface elevations. The profile drawing will provide an overall view of the roadway/existing ground elevations with respect to the various storm design frequencies for the length of the project. This will enable the State to determine the most feasible proposed roadway profile. These profiles must be submitted to the State and approved before continuing with the preparation of the comprehensive drainage report. NOTE: THE ENGINEER SHALL COORDINATE WITH ALL GOVERNMENT AGENCIES THROUGH THE STATE’S DISTRICT OFFICE. a. Manhole head losses shall be computed as per the State’s direction. Also, THYSYS (WINSTORM) computations are not needed for hydraulic grade line investigations. The head losses shall be computed with a pressure flow equation generally applicable to pipe running full flow. A hydraulic grade line starting at the outfall channel will be determined for each storm sewer system in order to obtain a design tailwater for each existing system. The design tailwater shall be the starting basis for the design of the proposed storm sewer system. b. For drainage areas, the Engineer shall limit the outfalls into existing storm sewer to existing capacity flows, which will be determined by the Engineer. Alternate flow routes, if feasible, shall be looked into for relieving storm sewer overload. The amount of the total detention storage to control storm sewer runoff for the design frequency shall be determined based on hydrograph routing, as well as a rough estimate of the available on-site volume. c. Drainage areas and flows for cross culvert drainage systems shall be determined as part of the comprehensive drainage report. Once determined, the sizing of the drainage crossings, hydrologic and hydraulics information will be provided to the State. DocuSign Envelope ID: 6D01D1D9CCC15E4F-025E-45ED-8647-6E7F-481D-80FF-D7092F6A0AEE4B6C2DCF3710 d. The Engineer shall prepare a report signed, sealed and dated by a registered/licensed engineer and shall include the preliminary findings of the storm sewer capacities, requirement for line rerouting, preliminary detention storage volumes based on hydrograph and initial recommendations on how to mitigate the storm impact on the receiving streams. The report shall also include preliminary sizing of the trunk line for the proposed gravity storm sewer within the limits of the project, conceptual and generic discussions of the alternatives considered, a comparative cost associated with each alternative and a recommended solution. e. Recommendations at this point should be generic and conceptual in nature, mainly for discussions with the State and the local government entities. An impact analysis is required on bayous, creeks and ditches as related to the State and FEMA criteria 10 and 100 year storm. The State’s required approach for impact prediction is as follows: a. Drainage areas for the existing and proposed conditions. b. Identify the existing drainage outfalls. c. Compute right of way corridor 100 year flood plain volumes for existing and proposed roadway elevations. A decrease in 100 year flood plain volumes is not allowed by the State or other governmental agencies, without adequate offsite mitigation. d. Compute existing and proposed peak flows by using hydraulics and hydrologic methodology and computer models. The additional lanes should be accounted for by increasing percent development. e. Storage computations will be based on hydrograph calculations and peak flows obtained in the item above. A mitigation volume for the 100 year storm will be computed. f. Analyze existing and proposed drainage system and quantify the increase in 100 year peak flows resulting from the roadway improvements. g. Hand calculations shall be provided which quantify the cut and fill within the 100 year flood plain, if any occur. h. Prepare conceptual 100 year sheet flow analysis for project utilizing existing and proposed conditions. i. Obtain current hydrologic and hydraulic computer models from government agencies and review and comment on the models. j. Current models will be updated to existing condition using the available State aerial photographs, and submitted to governmental agencies as the revised existing condition model. k. Analyze proposed roadway and outfall drainage improvements to quantify impacts to revised existing condition model. This contract does not include the detailed design of outfall improvements outside of the right of way, except for ditch outfall transitions of cross drainage culvert structures to the existing ditch.