Drainage Study. When authorized, conduct a detailed study to explore alternative design concepts concerning drainage for the PROJECT. Present the findings in writing identifying recommendations to the CITY, including preliminary cost estimates, prior to development of field check plans. Such written findings and recommendations must be in a format which is self-explanatory and readily un- derstood by persons with average backgrounds for the technology involved.
Drainage Study. 1. Perform a drainage study of the project watershed
1. Determine the drainage requirements for the project.
1. The study will consider the location of retention ponding areas for storing runoff from the project. The study will be documented in a bound Drainage Study report signed and sealed by a Registered Professional Engineer in the State of Texas .
2. The study will identify any right of way requirements for locating and constructing new ponding areas and/or other drainage appurtenances required for the project..
2. Coordinate with the County, TxDOT, and adjoining developers to check that all proposed drainage systems accommodate the proposed construction.
3. Design services will include the following:
1. Prepare drainage area maps.
2. Prepare culvert plan and elevation sheets.
3. Prepare plan/profile sheets for storm drain systems and outfall ditches.
4. Select standard details from County or TxDOT list of standards for items such as inlets, manholes, junction boxes and end treatment, etc.
5. Prepare details for non-standard inlets, manholes and junction boxes.
6. Prepare drainage details for outlet protection, outlet structures and utility accommodation structures.
7. Identify pipe strength requirements.
8. Prepare drainage facility quantity summaries.
9. Identify potential utility conflicts and design around them, wherever possible.
10. Take into consideration drainage impacts to pedestrian facilities, utilities, driveways, retaining walls and concrete traffic barriers.
11. If applicable, prepare Hydraulic Data Sheets for any bridge or cross drainage structures at outfall channel. (Indicate site location such as name of creeks and stations)
12. Develop plans for all temporary drainage facilities necessary to allow staged construction of the project and to conform with the phasing of adjacent construction projects without significant impact to the hydraulic capacity of the area. • Prepare design layouts, drainage area maps, and design of all drainage components. The Engineer shall design all conventional storm drainage and cross drainage in conformance with El Paso County design guidelines. • Storm drain design will be performed using WinStorm or GEOPAK Drainage. Cross drainage design will be performed using WINSTORM, HY 8 or HEC RAS • Three copies of the bound Drainage Study report.
Drainage Study. At the City’s written request, the Consultant shall: Prepare a drainage study for the project in addition to the work provided in exhibit A.
Drainage Study. The Consultant will prepare, submit, and obtain approval of a Drainage Impact Analysis. This analysis will identify the changes in peak flows due to the proposed roadway improvements and recommend drainage measures to mitigate the impacts associated with the proposed improvements. This study will include the evaluation of the existing storm sewer systems and recommend preliminary size detention basin or an enlarged storm sewer system so as not to impact the receiving streams or the abutting property. The purpose of this task is to prepare a Drainage Mitigation Impact Analysis Study to determine the 100-year storm impacts resulting from construction of the project and to develop and analyze alternatives to mitigate these impacts. The following tasks describe the work to be performed: Prepare 100-year storm drainage area maps for existing and proposed conditions, which includes the southbound lanes, within the project right of way (ROW) and any off-site areas draining into the ROW. Compute existing and proposed peak flows with standard TxDOT methodology within the ROW. The Rational Method will be used to compute these flows for drainage areas less than 200 acres and the Small Watershed Method will be used to evaluate the impacts of the ultimate conditions. HEC- HMS modeling will be used for drainage areas equal to or greater than 200 acres. Compute required 100-year storage volumes within the ROW using the average end area method to determine mitigation requirements for the proposed condition versus existing conditions. Prepare existing and proposed hydrographs at each outfall location to develop mitigation alternatives to implement the required 100-year mitigation. Alternatives may include increasing storm sewer sizes beyond what is required for the design 10-year storm or improving existing roadside ditches/ or providing a detention site required within the vicinity. The location of the detention site may vary and further analysis depending on the location will be needed. Prepare construction cost estimates for mitigation alternatives developed in the previous task to assist in selecting the most cost effective mitigation methods. Prepare a Drainage Mitigation Study report to summarize and document the findings of this study. The report will include the following items at a minimum: o Conceptual and generic discussions of mitigation alternatives considered o Comparative costs associated with each alternative o Recommended mitigation solutions o...
Drainage Study a. HYDROLOGIC/HYDRAULIC MODELING (1 major channel crossing, 7 cross drainage structures assumed): • Prepare hydrologic and hydraulic models or modify existing models (FEMA, drainage districts, river authorities, cities, etc.) if available, to define the drainage infrastructure required for the project. Detail the methodologies employed and recommendations. The analysis will include: preparation of a preliminary design of the right of way drainage system; preliminary sizing of cross drainage structures and major channel crossings to reflect the existing and proposed conditions; recommended minimum pavement elevations based on cross drainage flood elevations; right-of-way requirements; identify potential needs for FEMA Coordination. HEC-RAS shall be utilized for all stream modeling. HY-8 shall be used for non-bridge class culverts. • Develop existing channel cross sections based on data collection. • Exhibits and analysis will be prepared in the GIS environment to the extent practical. • Onsite parallel drainage for ditch and/or storm sewer sizing will only be analyzed to determine project ROW needs. Detailed inlet level calculations are not included in this scope. • Coordinate with the Upper Brushy Creek Water Control Improvement District (UBCWCID) as necessary throughout the project.
b. FEMA COORDINATION: • Coordinate with Local Floodplain Administrator as necessary throughout the project.
Drainage Study. 1. Perform a drainage study of the Project watershed to determine the drainage requirements for the Project.
1. The study will consider the location of retention ponding areas for storing runoff from the project. The study will be documented in a bound Drainage Study report.
2. Prepare layouts, drainage area maps, and design of all drainage components. The Engineer shall design all conventional storm drainage and cross drainage in conformance with El Paso County design guidelines.
3. Storm drain design will be performed using WinStorm or GEOPAK Drainage. Cross drainage design will be performed using WINSTORM, HY 8 or HEC RAS.
4. Coordinate with the County, TxDOT, and adjoining developers to check that all proposed drainage systems accommodate the proposed construction.
5. Design services will include the following: • Prepare drainage area maps. • Take into consideration drainage impacts to pedestrian facilities, utilities, driveways, retaining walls and concrete traffic barriers.
Drainage Study. Analyze the existing pre-development and post- development stormwater runoff calculations and determine the potential capacity and adequacy of the receiving system. Design stormwater treatment, infiltration chamber system, and infiltration and peak flowrate control devices. Prepare a drainage study to be submitted to the City of Nashua.
Drainage Study. Drainage studies will not be a part of this scope.
Drainage Study. In support of the need for a City floodplain permit, Xxxxxxx will evaluate the existing flood model for Village Creek. As the intent is to construct the new parking lot at the same elevation as the existing ground, it is anticipated that this study will be used to confirm no net rise. The study will be provided to the City as part of the floodplain permit process. It is assumed that the City will be able to provide the FEMA model for Village Creek. The deliverable will be a technical memo and submittals to FEMA for CLOMR/LOMR are not included. Proposal for Professional Services Oak Valley - South Xxxxx Street Trailhead Page 4
Drainage Study. Insight agrees that prior to development of an Insight Parcel, Insight shall prepare and submit for approval an updated hydrologic and hydraulic drainage study for the applicable Insight Parcel (the “Applicable Drainage Study”), and agrees that development of the applicable Insight Parcel shall be in compliance with the Applicable Drainage Study.
