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Danee McGee, PE, CFMStormwater Rehabilitation and XPSWMMCrystal Williams, PE, CFM, LEED APCameron Long, PE,

Stormwater Improvement Projects Charlotte Mecklenburg Stormwater Services2 | Stormwater Rehabilitation and XPSWMMOctober 29, 2015Process:SurveyExisting ConditionsCity Design StandardAlternative AnalysisSelected AlternativeDesignReal EstateBidConstruction

Goal: To provide a storm drainage system that is safe, clean, and cost effective

Hill Street SDIPExisting Conditions3 | Stormwater Rehabilitation and XPSWMM October 29, 2015

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Hill Street SDIP4 | Stormwater Rehabilitation and XPSWMM October 29, 2015Urban Environment Drains 25% of downtown CharlotteExisting Environmental ConcernsExtensive Existing Utilities to avoid or relocateExisting systems underneath buildings

Hill Street SDIP Urban Environment5 | Stormwater Rehabilitation and XPSWMM October 29, 2015

XPSWMM was determined to be the best option for modeling this system due to the limited open channels, and highly urban nature of the watershed. XPSWMM is a dynamic hydraulic and hydrologic modeling software thatcombines 1D calculations for pipe flow with 2D overland flow calculations in order to fully understand the project area storm system and flooding issues.Hill Street SDIPExisting Conditions Modeling Software6 | Stormwater Rehabilitation and XPSWMM October 29, 2015

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Hill Street SDIPExisting Conditions Creating the Model7 | Stormwater Rehabilitation and XPSWMM October 29, 2015Base ModelLoad in TIN surfaceSet Rain Data and Area (SCS Method or Rain on Grid)Load in Grid Extents (everywhere you want water to flow), set Grid cell size and orientation.Set Land Use/Roughness

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Hill Street SDIPExisting Conditions Creating the Model8 | Stormwater Rehabilitation and XPSWMM October 29, 2015

Inlets and Pipes Linked to Surface

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Hill Street SDIPExisting Conditions Creating the Model9 | Stormwater Rehabilitation and XPSWMM October 29, 2015

ChannelsPull Cross Sections directly from SurfaceLink Channel to Surface1D/2D Interface 1D/2D Connections

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Hill Street SDIPExisting Conditions Creating the Model10 | Stormwater Rehabilitation and XPSWMM October 29, 2015Buildings (& roof drainage)

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Interactive InterfaceDepthsVelocitiesFlowsExportingTablesProfileVideosImages

Hill Street SDIPExisting Conditions Viewing the Results11 | Stormwater Rehabilitation and XPSWMM October 29, 2015

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A significant storm event occurred on August 5, 2011 where photos and videos of the flooding in the project area were taken and providedRain data was obtained from nearby rain gauge, and the storm event was run through the Existing Conditions XPSWMM Model for Hill StreetThe validation storm event produced results similar to field observationsHill Street SDIPExisting Conditions Validation Storm12 | Stormwater Rehabilitation and XPSWMM October 29, 2015

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Hill Street SDIPExisting Conditions Validation Storm13 | Stormwater Rehabilitation and XPSWMM October 29, 2015

Hill Street SDIPExisting Conditions Validation Storm14 | Stormwater Rehabilitation and XPSWMM October 29, 2015

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Hill Street SDIPExisting Conditions 100yr6hr Storm15 | Stormwater Rehabilitation and XPSWMM October 29, 2015

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Hill Street SDIPExisting Conditions Deficiencies 17 | Stormwater Rehabilitation and XPSWMM October 29, 201575% of pipes are deficient40% of channels are deficient100% of culverts are deficient40% of inlets are deficient70% of buildings are potentially flood-prone

Hill Street SDIPProposed Conditions 18 | Stormwater Rehabilitation and XPSWMM October 29, 2015

Realign New Storm System

Realign New Storm SystemSystem Improvements to Reduce Flooding/Repair Infrastructure

Increase Pipe and Culvert Size for SystemRealign New Storm System Along Morehead St.Convert Open System to Closed System

Utility Repair/ Relocate Throughout ProjectAdd Inlets Along Morehead St. and Throughout Project

Hill Street SDIPProposed Conditions 19 | Stormwater Rehabilitation and XPSWMM October 29, 2015Based on nearly 20 different criteria for pipes, channels, inlets, etc., the following improvements are necessary: 4.1 miles of Proposed Storm System 459 Proposed Storm Drainage Structures Approximately 4000 LF of Utility Relocations

Hill Street SDIPProposed Conditions 100yr6hr Storm20 | Stormwater Rehabilitation and XPSWMM October 29, 2015

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Questions?21 | Stormwater Rehabilitation and XPSWMM October 29, 2015