Schmidt, Michael

Michael Schmidt is the Global Water Resource Infrastructure and Resilience Practice Leader for CDM Smith with 40 years of experience in sustainable and resilient stormwater, green infrastructure, coastal and ecosystem programs for more than 500 projects in 35 US States and in nine countries on six continents.

Titles from this speaker

A Resilient Stormwater and Coastal Management Plan for Hollywood Florida

Abstract

INTRODUCTION & BACKGROUND The City of Hollywood, Florida, developed a Stormwater Master Plan (SWMP) to evaluate and model the City's watersheds and identify resilient stormwater and flood prevention capital investments for today, tomorrow, and decades to come. The master plan includes modeling the effects of sea level rise (SLR), rising groundwater tables, and increased rainfall intensities. It also considers anticipated development growth and climate change data, providing the tools necessary for the City to create a forward-thinking capital plan that anticipates and prioritizes funding and infrastructure needs. Program goals were established to create a vision and metrics for the future. Topics include:

*Flood control

*Water quality protection

*Aquifer recharge and water supply

*Conservation and stormwater harvesting

*Operation and maintenance

*Long-term financing

*Community acceptance The City of Hollywood encompasses approximately 45 square miles (Figure 1). The stormwater service area is divided naturally by elevation, topography, and infrastructure into three major basins. These basins interact with Broward County, Central Broward Water Control District (CBWCD), South Broward Drainage District (SBDD), Florida Department of Transportation (FDOT), City of Hallandale Beach, City of Dania Beach, and South Florida Water Management District (SFWMD) stormwater systems. APPROACH Using the United States Environmental Protection Agency's (EPA) Storm Water Management Model (SWMM), the SWMP hydrologic and hydraulic models were developed for the City's primary stormwater management system (PSMS). The models included a study area of 29,000 acres, 2,228 sub-basins, consideration of offsite basin and major canal contributions, 80 backflow preventers, 12 stormwater pump stations, 217 miles of stormwater pipes, 29 miles of canals, 15 bridges, 33 miles of exfiltration trench, 250 outfalls, and a one-year tidal stillwater elevation of 2.5 feet North American Vertical Datum (NAVD). The SWMP involved coordinating the City's geographic information system (GIS) to update the existing stormwater atlas, populating an asset management database. Simultaneously, a city-wide stormwater model was developed, accounting for pervious and impervious areas in the urban landscape. The data collection effort included a survey of stormwater structures and the development of a Digital Elevation Model (DEM) based on Light Detection and Ranging (LiDAR) topographic data. The data collected was validated with the City's existing infrastructure and bathymetric data to develop a City-wide model for the major watersheds that accounts for varying rainfall events, tidal and groundwater influences, and future SLR impacts in coordination with Broward County, SBDD, CBWCD, Dania Beach, Hallandale Beach, FDOT, and SFWMD stormwater systems. Modeling inputs and parameters required extensive manipulation and analyses using GIS tools such as the Geographic Watershed Information System (GWIS) schema and ArcHydro. The modeling provides a comprehensive basin-by-basin analysis of the flood control level of service (LOS) for existing and proposed stormwater systems. It also considers the effects of projected climatological conditions for the future. The City conducted a series of public meetings for citizens to provide locations of reported problems. The input, combined with the City's stormwater complaint system records and Federal Emergency Management Agency (FEMA) Flood Insurance Rate Maps (FIRM), defined flooding problem locations and system connectivity (Figure 2). The project team used SWMM to estimate flood stages and inundation maps (Figure 3). They evaluated the flow rates and volumes for storage, conveyance, exfiltration, recharge wells, and potential pumping. The plan included conditions for the April 2023 flood event, ranging from a five-to-1,000-year event. Individual neighborhood capital improvement projects were tailored, specifically in areas most susceptible to flooding. Swales, detention systems, and exfiltration systems were evaluated, along with time-varying storage operations and recharge wells. The team is also considering seawall height extensions for the City's 140 miles of shoreline and backflow prevention for the 250 outfalls. SUMMARY This paper will present the results of the SWMP focusing on coastal resilience. It encompasses hydrologic and hydraulic models, historical storm tidal surge evaluations, LOS evaluations, cost-effective alternatives assessments, and associated Capital Improvement Program (CIP). This presentation includes a summary discussion on stakeholder coordination and prioritization strategies.

The City of Hollywood Florida faces challenges of dense development impacted by sea level rise, tidal surge events, and varying precipitation. The Stormwater Master Plan is a holistic program that accounts for changes in these areas to manage flooding while protecting and enhancing water quality and aquifer recharge. A multi-faceted approach to modeling current/future conditions was used to guide cost effective capital improvements and policies for current/future stormwater and resilience.

SpeakerSchmidt, Michael

Presentation time

09:00:00

09:30:00

Session time

08:30:00

10:00:00

SessionResilient Development: Insights from Urban and Coastal Areas

Session number512

Session locationRoom 243

TopicAdvanced Level, Stormwater and Green Infrastructure, Sustainability and Climate Change

Author(s)

Schmidt, Michael, Goldman, Jonathan, Nye, Thomas, Jiang, Feng (Jeff), Morello, Vincent

Author(s)M.F. Schmidt1, J. Goldman1, T.E. Nye1, F. jiang2, V. Morello2

Author affiliation(s)1CDM Smith Inc., 1CDM Smith Inc., 2City of Hollywood

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Oct 2024

DOI10.2175/193864718825159714

Volume / Issue

Content sourceWEFTEC

Word count11

Description: How the City of Miami is Using Technology to Help Plan for Management of Urban...

How the City of Miami is Using Technology to Help Plan for Management of Urban Flooding in the Face of Sea Level Rise

Abstract

The City of Miami faces unique climate change-related challenges. With a sea level that is projected to rise significantly over the next 40 years, the City needed a plan to protect public safety and vulnerable assets and provide a strategy to combat the ever-increasing impacts of climate change. The City of Miami developed an innovative SWMP and climate change strategy that included an extensive Geographic Information System (GIS) data development, dynamic stormwater models, and innovative engineering solutions. The City of Miami's Stormwater Master Plan was developed as a holistic effort to digitize and model existing infrastructure with anticipated development and climate data to allow the City to identify cost-effective existing and future stormwater capital investments. From a technology perspective, the City's SWMP and climate change strategy involved: -Implementation of an extensive stormwater GIS environment that provided the foundation for the modeling process. This process involved digitization of more than 30,000 pages of existing as-builts drawings, extensive Global Positioning Satellite (GPS) data location and subsurface mapping, and development of GIS and integrated asset management databases. -Acquisition of LiDAR topographic data using digital sensors and completion of high-accuracy topographic field survey of critical assets including more than 90 miles of coastal perimeter for seawalls and the primary stormwater management system (PSMS) which consists of pipes and channels greater than 24 inches in size or equivalent. -Implementation of web, mobile, and dashboard solutions to support the data collection process, visualization of data, and sharing of information between the City and the project team. -Development of a city-wide United States Environmental Protection Agency (USEPA) Storm Water Management Model (SWMM) for hydrology and hydraulics that takes into consideration pervious and impervious areas of the urban landscape. This model was used to plan and prioritize future stormwater infrastructure investments in response to chronic flooding and an ever-changing climate. -Application of the Federal Emergency Management Agency (FEMA) Hazards United States (HAZUS) tool for benefit-cost analyses using GIS data to enumerate flood damages and flood damage reduction and confirm cost-effectiveness Once the data collected was validated, models were developed for the City's eight major stormwater basins. These models incorporated data from the City's PSMS and account for tidal and groundwater influence and two future seal level rise scenarios. Modeling inputs and parameters required extensive manipulation and analyses using GIS tools such as the Geographic Watershed Information System schema (GWIS) and ArcHydro. When completed, by blending several technology environments the models and resultant data provided a comprehensive basin-by-basin analysis of the level of service (LOS) for both existing and proposed stormwater systems, with consideration of the effects of future projected climatological conditions. The City's project team then evaluated alternative conceptual solutions for individual neighborhood capital improvement projects, specifically in areas found to be most susceptible to flooding. The plan provides the City: -A new detailed, dynamic, and comprehensive city-wide stormwater model to simulate predicted rainfall flooding and the effects of sea level rise and storm surge on the existing and proposed stormwater management system. The model can be modified and enhanced in the future as new projects come online or system conditions change. -A city-wide CIP to cost-effectively mitigate flooding issues for two alternative levels of service and a prioritized list of project areas and improvements with planning-level budgets at the neighborhood scale. -Increased aquifer recharge to reduce saltwater intrusion for future potable water supply and water quality treatment improvements to protect Biscayne Bay. -A benefit-cost analysis for the proposed improvement alternatives. -A modern GIS database with digital mapping and metadata to archive and access the City's vast stormwater assets and record document plans linked to the stormwater model. -A foundation and roadmap plan for stormwater and coastal resiliency in the future. -A series of comprehensive stormwater management strategies which are permittable and can be implemented in a prioritized, phased program. These strategies help address the City's chronic flooding, improve stormwater and coastal resiliency, and provide strategies for sea level rise. During this presentation the process for how the City used modeling, GIS, dashboard, mobile, and web technologies to develop an evolving strategy that will help the City combat flooding and the effects of sea level rise will be presented and evaluated.

This paper was presented at the WEF/AWWA Utility Management Conference, February 21-24, 2022.

SpeakerSchmidt, Michael

Presentation time

09:30:00

10:00:00

Session time

08:30:00

10:00:00

SessionResilience

Session number28

Session locationHyatt Regency Grand Cypress, Orlando, Florida

TopicCapital Planning, Climate Change Adaptation, Climate Change Mitigation, Decision Making, Flooding, GIS, Resiliency, Stormwater, Water Resources

Author(s)

J. BrennenM. SchmidtC. BennettJ. Goldman

Author(s)J. Brennen 1; M. Schmidt 2; C. Bennett 3; J. Goldman 4

Author affiliation(s)CDM Smith 1; CDM Smith 2; City of Miami 3; UMC Speaker 4

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Feb 2022

DOI10.2175/193864718825158222

Volume / Issue

Content sourceUtility Management Conference

Word count24

Miami Forever: Resilient Stormwater and Coastal Management for a Changing Climate

Abstract

Miami faces challenges with dense development being impacted by sea level rise, tidal surge events, and varying precipitation. The Stormwater Master Plan is a holistic plan that accounts for changes in sea levels and tidal surge, groundwater, and rainfall patterns to manage flooding while protecting and enhancing water quality and aquifer recharge. A multi-faceted approach to modeling current and future conditions allows the city to plan for current and future climate stormwater and coastal resilience needs. This paper presents the SWMP challenges, opportunities, methodology, level of service for the stormwater system, benefit-cost analyses, and considerations for implementation.

The City of Miami faces challenges with built-out urban conditions being impacted by sea level rise, tidal surge events, and varying precipitation. The Stormwater Master Plan is a comprehensive program to manage stormwater with changes in sea levels and tidal surge, groundwater, and rainfall patterns to manage flooding while protecting and enhancing water quality and aquifer recharge. The holistic approach to modeling current and future conditions allows the city to plan for current and future climate stormwater and coastal resilience needs. This paper presents the challenges, opportunities, methodology, levels of service for the stormwater system, benefit-cost analyses, and considerations for implementation.

SpeakerSchmidt, Michael

Presentation time

16:22:00

16:37:00

Session time

16:00:00

17:30:00

SessionWhen the Rain Comes Down and the Seas Go Up

Session number320

TopicStormwater, Green Infrastructure, and Wet Weather, Sustainability and Climate Change

Author(s)

Michael Schmidt

Author(s)M.F. Schmidt1; C. Bennett2;A. Dodd3;J. Goldman4;T. Nye5;

Author affiliation(s)CDM Smith, Jacksonville, FL1City of Miami, Department of Resilience and Public Works2,3CDM Smith, Boca Raton, FL4,5

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Oct 2021

DOI10.2175/193864718825158081

Volume / Issue

Content sourceWEFTEC

Word count12

Utilization of Computational Fluid Dynamics Modeling to Optimize Design

Abstract

The Nansemond Treatment Plant (NTP) Advanced Nutrient Reduction Improvements (ANRI) Phase II improvements project is a vital component of Hampton Roads Sanitation District's (HRSD) overall Sustainable Water Initiative for Tomorrow (SWIFT) Program to improve nutrient waste load reductions to the Chesapeake Bay watershed. This project consists of expanding the existing NTP facility to 50 MGD to accommodate the transfer of screened and equalized raw wastewater from the Boat Harbor (BH) service area. It also includes process improvements to prepare for the next phase of SWIFT improvements at the NTP. As part of the design, of these improvements Computational Fluid Dynamics (CFD) Modeling was utilized for several unit processes to optimize design and construction. These included:

*Influent Distribution Box (IDB) Mixing and Flow Distribution: A new IDB is being constructed to combine influent flows from the Nansemond service area and the BH service area and distribute them equally to the downstream primary clarifiers. CFD modeling was used to evaluate the effectiveness of mixing these flows completely prior to flow splitting. The results indicated the need for a mixing chamber followed by a perforated baffle wall to evenly distribute the flow and reduce the approach velocity of the combined flow prior to splitting flows to the primary clarifiers using proportional length weir gates. CFD modeling results for the IDB are shown in Figure 1.

*Backflow modeling for partial denitrification annamox (PdNA): The density difference between wastewater in anoxic and aerobic zones can cause buoyancy-driven counterflow (BDCF), potentially impacting biological nutrient removal and increasing methanol consumption for denitrification. BDCF is a hydraulic phenomenon that occurs due to a density difference between interfacing fluids, causing a pressure gradient and resultant counterflow between the liquid zones. CFD modeling was performed to understand the impact of BDCF at the first anoxic/aerobic zone and aerobic/second anoxic zone interfaces for the aeration tanks. Modeling indicated significant BDCF was likely occurring between the first anoxic and aerobic zones reducing process efficiency. A hood-shaped baffle system was designed to reduce BDCF while minimizing head loss across the system. Figures 2 and 3 show BDCF before and after implementation of the baffle system.

*AAA Basin Flow Distribution: Hydraulic modifications are being made to accommodate higher flow rates through the existing AAA basins. The AAA basins consist of 7 trains, each subdivided into six cells using baffle walls. The flow split to the basins is dictated by the hydraulics through the baffle walls. Maintaining similar hydraulic losses through each basin is critical to maintain even flow split. To accommodate higher flows through each basin due to the plant expansion, openings in the baffle walls needed to be added and/or widened. As each basin's modifications are completed sequentially, the hydraulic losses through the basins will differ causing a variation in the hydraulic flow split to occur. To maintain desired flow distribution to each basin throughout construction, CFD Modeling was performed to evaluate the expected flow split under various flows and operating conditions. Based on the results of the modeling, temporary modifications to the inlet of each basin using temporary orifice plates for each phase of construction were developed. This allows a more even distribution of flows to each of the basins will be maintained throughout construction. An example of the flow distribution is shown in Figure 4.

*Secondary Clarifier Influent Channel Flow Distribution: Two additional 160-ft secondary clarifiers are being added to the plant with this project, for a total of four 160-ft diameter clarifiers and three 85-ft diameter clarifiers. The flow from nine process trains discharge to a common flow distribution channel prior to overflowing flow splitting weirs to the clarifiers. The clarifier influent distribution channel extends over 500 ft with proportionally sized flow splitting weirs spread out along the distribution channel. However, proportional flow split at the weirs was not occurring due to the hydraulic conditions along the channel. CFD Modeling was performed to evaluate the expected flow split under various flows and operating conditions. Initial modeling indicated a significant deviation in flow split to the clarifiers. Modifications to inlet weir plates, installation of adjustable weir gates, and an operational strategy for operating the inlets to the clarifiers was developed based on the results of the modeling to more evenly distribute flows to the secondary clarifiers. The presentation will provide details of the various CFD Modeling performed, options that were developed to optimize the design, the results of those changes in the CFD models, and how these improvements were implemented in the design.

This paper was presented at the WEFTEC 2024 conference in New Orleans, LA October 5-9.

SpeakerHanson, Rachel

Presentation time

16:00:00

16:30:00

Session time

15:30:00

17:00:00

SessionOptimizing Design for Increased Capacity

Session number228

Session locationRoom 349

TopicFacility Operations and Maintenance, Intermediate Level, Municipal Wastewater Treatment Design