Sauer, Andrew

Andy is the National Stormwater Management Practice Leader at Burns & McDonnell Water Global Practice, specializing in innovative wet‑weather and green infrastructure solutions for complex urban environments. Andy serves as Chair of the WEF Stormwater Policy & Governance Subcommittee and is a frequent lecturer on urban stormwater design and practical implementation approaches. His work focuses on advancing resilient, cost‑effective wet weather solutions that enhance community value and long‑term system performance.

Titles from this speaker

Description: Cost Effective Urban Flooding Solutions: Advancing a 1D/2D Modeled Concept to...

Cost Effective Urban Flooding Solutions: Advancing a 1D/2D Modeled Concept to Implementation Through Progressive Design Build in Kansas City’s Westport District

Abstract

Kansas City, Missouri, initiated a comprehensive flood mitigation effort in the Westport district to address recurring urban flooding within a dense, highly constrained combined sewer basin. The 2022–2023 study phase employed InfoWorks ICM with fully integrated 1D pipe network modeling and 2D surface flow routing to simulate historical rainfall events and quantify both existing hydraulic deficiencies and the performance of alternative improvement strategies. The modeling framework supported evaluation of multi objective green–gray infrastructure configurations, including distributed surface collection, subsurface storage, controlled conveyance, and streetscape modifications. The preferred concept demonstrated substantial flood volume reduction and level of service improvements while reducing projected capital costs by tens of millions of dollars compared to traditional conveyance only solutions. To accelerate delivery and maintain design intent, the City advanced the project using a progressive design build (PDB) approach. This delivery method enabled early contractor involvement, iterative model based optimization, and collaborative risk management for challenges including limited right of way, multimodal corridor reconstruction, utility conflicts, and integration of underground storage within an active urban entertainment district. The design incorporates modular storage units with continuous monitoring and adaptive controls, pervious paver systems for distributed infiltration and storage, and a rebuilt multimodal Mill Street corridor that balances hydraulic performance with operational and urban design requirements. Construction began in February 2025 and is scheduled for substantial completion before the 2026 World Cup. This presentation will detail the hydraulic modeling methodology, design optimization enabled by PDB delivery, and the integrated stormwater, transportation, and urban realm improvements that allowed Kansas City to move from concept to implementation in under two years while achieving significant cost savings and enhanced system resilience.

This paper was presented at WEFTEC 2026 in New Orleans, Louisiana.

Presentation time

09:30:00

10:00:00

Session time

8:30:00

10:00:00

SessionManaging Urban Flood Risk in Constrained Systems

Session locationErnest N. Morial Convention Center

TopicClimate Change Adaptation and Metrics, Collection Systems, Stormwater and Green Infrastructure, Watershed Management, Water Quality, and Groundwater

Author(s)

Sauer, Andrew, Moore, Lauren

Author(s)A. Sauer1, L. Moore1

Author affiliation(s)Burns & McDonnell Engineering Company, Inc., 1Burns & McDonnell Engineering Company, Inc., 1

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Sep 2026

DOI10.2175/193864718825160555

Volume / Issue

Content sourceWEFTEC

Word count22

Description: Creating Affordable Multi-benefit Flood Solutions Within a CSO Basin Requires Bigger...

Creating Affordable Multi-benefit Flood Solutions Within a CSO Basin Requires Bigger Thinking

Abstract

The Westport Regional Business League (WRBL) in conjunction with the City of Kansas City, Missouri (City) is finally addressing frequent and severe flooding within the Westport district of the Brush Creek combined sewer overflow (CSO) basin. This project is applying a multi-objective approach to design a more affordable and valuable solution. The overall objective was to significantly reduce flood depths at a more affordable cost within a combined sewer basin. The project team achieved this objective by first developing a detailed 2D stormwater model that accurately simulated historical flood depths and then used that model to inform the city and key stakeholders on the flood reduction benefit for a range of solutions. Overlaying the 2D model results over parcel and street information served as a clear communication tool to demonstrate the flood reduction benefit. Unlike typical stormwater designs the goal was not to eliminate flooding, but to reduce the flooding to a point that property was not damaged, and public roads could be passable. Westport's flooding problems have gone through numerous studies in the past. These efforts have ultimately resulted in solutions that were held to a traditional stormwater design standard that was not affordable or constructible within this highly developed and utilized area of the city. The City and WRBL are now interested in pursuing stormwater solutions that can improve their frequent flooding problems, outside of a traditional stormwater design standard. The project team approached this effort using available rainfall data for two recent rain events and targeted stormwater improvement solutions that would alleviate flooding for these historical events using an Infoworks ICM 2-Dimensional Model. This tool was developed to accurately reflect observed flooding conditions for the recent rain events to understand how much reduction in flood depth the proposed improvements could provide. While "solving" flooding problems in Westport for all storm events is not a feasible goal, the project seeks to significantly improve the flooding conditions for the more frequent rainfall events. Reducing flood depths from over 1.22 m (> 4 feet) to less than 0.15 m (< 6 inches) can transform what has historically been expensive flood damage to buildings and vehicles to short-term ponding contained mostly within the street right-of-way. The 2D watershed model was then utilized to evaluate both green and gray stormwater improvement solutions. Gray stormwater improvement solutions included curb and grate inlets, collection piping to underground storage, and conveyance piping. Green stormwater improvement solutions included pervious pavements, bioretention, vegetated swales, and tree planters. A combination of green and gray stormwater improvement alternatives was evaluated with the 2D stormwater model for a range of rainfall events. Stormwater improvements were sized and located to align with the Westport District plan which included parking improvements, streetscape enhancements, increased pedestrian safety and connectivity while maintaining the historical significance of the area. Using this multiple objective integrated approach, the design team was able to develop a preferred improvement alternative that provided a flood reduction benefit, addressed the Westport District plan requirements, and was cost-effective. The preferred stormwater alternative is a system solution that collects, stores, and conveys stormwater at multiple locations. The preferred improvement solution is tens of millions of dollars less than previous solutions, which makes this project fundable by the city. The city plans to move this project forward to design and construction to finally solve this frequent and severe flooding in Westport. In addition, this integrated flood reduction project will have a significant impact on reducing the CSO volume discharged downstream to Brush Creek. During the design phase other project performance improvements will be evaluated including real-time controls of the storage volume, stormwater reuse opportunities, and integration of this project with another green infrastructure project downstream to increase the performance and maximize the benefit of both projects. Thinking bigger than just solving the flooding problems has resulted in a project that a broad range of stakeholders can support at a more affordable price.

Addressing frequent and severe flooding within the Westport district of the Brush Creek CSO basin required a 2D model to evaluate a range of events. Applying a multi-objective approach resulted in a more affordable and resilient solution. The overall objective was to significantly reduce flood depths at a more affordable cost within a combined sewer basin. A detailed 2D stormwater model accurately simulated historical flood depths which was used to demonstrate the flood reduction benefits.

SpeakerSauer, Andrew

Presentation time

16:30:00

16:50:00

Session time

15:30:00

17:00:00

SessionPredicting Flooding Before It Happens

Session locationRoom S504c - Level 5

TopicIntelligent Water, Intermediate Level, Stormwater and Green Infrastructure

Author(s)

Sauer, Andy

Author(s)A. Sauer 1; L. Moore 1 ; A. Sauer 1;

Author affiliation(s)Burns & McDonnell 1; Burns & McDonnell 1 ; Burns & McDonnell 1;

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Oct 2023

DOI10.2175/193864718825159132

Volume / Issue

Content sourceWEFTEC

Word count13

Creating Smart Stormwater Solutions in a Digital World

Abstract

Today we have the benefit of having digital data available at our fingertips. However, in the stormwater profession, are we ready to maximize the use of that data? Each project presents opportunities to maximize the application of this data and how we can best collect stormwater data today to further the digital world we live in. When we collect stormwater data are we thinking about how that data can be used in models to address watershed solutions? Are we thinking about how our modeling results can be used to engage stakeholders? We have the technical resources to keep up with the rapidly changing digital world; the challenge is applying those technical resource efficiently to maximize the use of the data. Ultimately, it is using data to create more sustainable and resilient solutions that reduce costs and increases public benefit while managing the risk associated with a changing climate. Our toolbox includes stormwater models. Stormwater models are used every day to simulate design and historical rainfall events. We use them to demonstrate the impacts and the benefit those stormwater solutions given our assumed inputs. We use models to map floodplains, to evaluate enclosed systems, and to predict future flooding based on land cover changes or increases in rainfall intensities. The potential uses are endless, but do we get the full benefit of the resources put into developing these models over time? Are we building an adaptable and transforming digital platform or are we just developing a list of static projects? For stormwater solutions to advance and be more adaptive, resilient, and sustainable we need to have a plan and a vision of how stormwater data should be collected, how that data is maintained, what that data is going to be used for, and, who is using the data. We can't keep doing stormwater modeling in a black box every 15-20 years. Stormwater data and the subsequent models need to be living and growing digital systems that are refined and updated regularly with an eye towards smarter stormwater solutions that provide greater long term public benefit. This presentation will address these issues using the City of Lawrence, Kansas as a case study. The City of Lawrence 20-years ago went through a typical stormwater master planning process that resulted in a list of projects. Many of those projects have been completed but stormwater issues remain and, in some cases, are worse. Instead of going through another typical stormwater master planning process, the City is fully understanding their stormwater system through comprehensive field evaluation of their assets; developing the processes and procedures for using digital data in comprehensive watershed models; using the results of the watershed models to define improvement projects and engage stakeholders; and to create a holistic, dynamic stormwater improvement plan. The field data was collected using the latest technology, organized within a stormwater asset management system, and delivered as geodatabases, shapefiles, and digital photos and videos to the modeling team. The modeling team then used that data with recent LiDAR to develop stormwater models of the enclosed system, the 2D overland flow, and the 2D open channels and streams. The stormwater models include PC-SWMM with 2D and HEC-RAS 6.0 2D. The model files were spatially referenced and fully integrated with the City's GIS. The model inputs and outputs were easily mapped and overlaid with other City GIS data. This resulted in digital stormwater data and model simulation results that formed the foundation for the development of an adaptive and dynamic stormwater improvement process. This process will allow the City to use the models to make decisions, update stormwater improvement plans periodically, and provide watershed visualization materials to educate and engage stakeholders on stormwater issues. This presentation will focus on stormwater modeling in the digital world and how the latest field data collection technology, asset management systems, and stormwater improvement projects can be done more effectively. Lessons learned in using digital data for model inputs, 2D modeling, and linking enclosed storm sewer models with open channel models will also be presented. And finally, a process will be presented of how this can be accomplished on a watershed scale to drive innovation, improve the resiliency of stormwater solutions, and reduce a city's overall stormwater improvement cost.

This paper was presented at the WEF Stormwater Summit in Minneapolis, Minnesota, June 27-29, 2022.

SpeakerSauer, Andrew

Presentation time

16:15:00

16:45:00

Session time

13:30:00

16:45:00

Session number14

Session locationHyatt Regency Minneapolis

TopicGIS, Hydrology & Hydraulics, Stormwater Management Design And Analysis

Author(s)

A. Sauer

Author(s)A. Sauer1; M. Bond2; M. Goedeken3

Author affiliation(s)Burns & McDonnell1; City of Lawrence, Kansas2; Burns & McDonnell3;

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Jun 2022

DOI10.2175/193864718825158482

Volume / Issue

Content sourceStormwater Summit

Word count9

Description: Green Infrastructure Maintenance. Applying the New Urban Stormwater Controls...

Green Infrastructure Maintenance. Applying the New Urban Stormwater Controls Operations & Maintenance Manual

Abstract

The effectiveness of stormwater control measures (SCMs), or green infrastructure, over time depends on how well it is established and then how it is maintained over time. Nationwide, the largest weakness of stormwater programs is assuring initial and long-term performance of SCMs. As more SCMs have been implemented the challenges of operation and maintenance of these facilities still remains. However, much can be learned by sharing and understanding the function of these facilities so that effective maintenance activities can be proactively scheduled to ensure the performance. Successful implementation of SCMs requires good design with maintenance in mind, proper construction, and long-term maintenance. Therefore, WEF and ASCE identified the need for a comprehensive book that describes the importance of incorporating maintenance considerations in the design and construction of SCMs. The Operations & Maintenance of Stormwater Control Measures Manual of Practice (MOP) responds to the need to address program and regulatory requirements and includes a description of the elements of an inspection and maintenance program, as well as the skill sets needed in modern maintenance crews. The MOP includes a chapter focused on utility/local programs and department of transportation programs to highlight the differences and special requirements of these programs. This session will provide an interactive session that will focus on the three sections of the Urban Stormwater Control Operations & Maintenance MOP (WEF Manual of Practice No. 39; ASCE/EWRI Manuals and Reports on Engineering Practice No. 153) that cover the maintenance requirements of SCMs from design through construction and then to long-term maintenance. Specifically, these three sections include: 3.0 Design & Construction Maintenance Considerations, 4.0 Conventional SCMs and Green Infrastructure Maintenance, and 5.0 Inspection and Maintenance During and after Construction. The session will provide real-world examples from KC Water's green infrastructure program along with examples from other cities. Participants will be asked to first define their biggest maintenance challenges and then discuss what works and doesn't work. The top three maintenance challenges will then be discussed in detail using information from the MOP and other participants examples to best address each maintenance challenge.

This paper was presented at the WEF Stormwater Summit, June 27-29, 2023.

SpeakerSauer, Andrew

Presentation time

11:45:00

12:15:00

Session time

10:45:00

12:15:00

SessionSession 02: It Won't Work if it's Broke (O&M)

Session number02

Session locationKansas City Convention Center

TopicImplementation and Construction, Operations and Maintenance, Stormwater Asset Management

Author(s)

Sauer, Andrew

Author(s)A. Sauer1; F. Pasquel2; B. Macke1; M. Van Auken2;

Author affiliation(s)Burns & McDonnell1; Arcadis2;

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Jun 2023

DOI10.2175/193864718825158943

Volume / Issue

Content sourceStormwater

Word count14

Integrated Urban Wet Weather Solutions Save Money and Provide More Benefits

Abstract

Dense urban areas face unique stormwater challenges that require broader, more holistic wet weather solutions, especially in the face of climate changes. Applying an integrated urban wet weather approach can save millions of dollars, address both water quantity and quality issues, and create more visible tangible benefits back to the community. In many cities, the current stormwater design criteria result in solutions that are too costly, too big to construct, and may, in fact, worsen the situation when considering shorter more intense rainfall events caused by climate change. Furthermore, cities may be spending money on infrastructure that adversely impacts other infrastructure, causing more downstream impacts, or creating systems that are not resilient or sustainable long-term. With the current state of the practice 2D wet weather models, integrated wet weather solutions can be developed, refined, and tested across a range of stormwater events to obtain the most cost-effective, resilient solutions. Using this approach results in a system approach to capture, control, and convey stormwater in a way that optimizes existing systems, integrates more resilient green infrastructure solutions to store and slow down the runoff, constructs new systems that match conveyance requirements, and considers surface storage and overland flow paths to route water without damaging property. The use of 2D wet weather models provides the ability for a utility to demonstrate performance versus applying an outdated presumptive approach to meet an outdated design standard. In Kansas City, MO, integrated urban wet weather solutions were developed within two urban watersheds, resulting in cost-effective solutions that were supported by the public and the utility because the performance could be demonstrated through the use of 2D models; the solutions also provided multiple benefits. The first example is the Brookside watershed which is a historic single-family residential area with more dense commercial areas at the top and bottom of the watershed. Intense rainfall events cause flooding of streets, homes, and businesses. The previous solution developed over ten years ago was to construct a very large conveyance system to fully convey the 10-year, 24-hour rainfall event. This solution had an estimated cost of approximately $40 million which was not affordable, so nothing was done and flooding continued. Applying an integrated urban wet weather approach, a 2D model was developed. The model revealed that the flooding was actually caused by overland flow and that a system of collection areas, improved overland flow paths, storage, and smaller conveyance pipes could mitigate the flooding. This solution had an estimated cost of $28 million, saving the City almost $12 million. The second example is the Westport entertainment district, the oldest area in Kansas City. The Westport area experiences frequent and severe flooding, causing damage to parked cars and businesses. This area has been studied numerous times over the years but with a single focus on meeting a required level of service-not an integrated wet weather focus. Using an integrated wet weather focus and a 2D model, a range of storm events were evaluated to determine the best solution. The best solution was defined by the business stakeholders with the help of the 2D model to demonstrate the performance of the preferred solution using real rainfall data. Using real rainfall data with the 2D model resulted in the need for a system solution that utilized green infrastructure, underground storage, conveyance pipes, and real-time controls. This system approach resulted in not only a stormwater solution that will reduce future flooding but also a solution that invests in this entertainment district, creating a new multimodal corridor that will support parking, walking, and vehicular traffic. The solution also met the district's comprehensive plan and provided the opportunity for a forgotten neighborhood to be able to celebrate its history in a new park. The final design concept saved the City more than $30 million while creating more visible benefits and will reduce combined sewer overflows. This project is now moving forward as a progressive design-build project which will allow the City to meet an aggressive schedule for completion before the World Cup in 2026. This presentation will use these two case studies as examples of how to implement an integrated urban wet weather solution approach, the benefits of this approach, and outcomes and next steps. It is not easy to change firmly established stormwater design criteria in urban areas but through an integrated urban wet weather evaluation, more holistic cost-effective and resilient solutions can be achieved. As we look to the future, we cannot necessarily implement the solutions of the past to meet our new goals of creating cities that are more livable, sustainable, and resilient to changes in climate.

This paper was presented at the WEF/AWWA Utility Management Conference, February 13-16, 2024.

SpeakerSauer, Andrew

Presentation time

09:00:00

09:30:00

Session time

08:30:00

10:00:00

SessionIntegrated Water Management

Session number31

Session locationOregon Convention Center, Portland, Oregon

TopicIntegrated Water Management / One Water

Author(s)

Sauer, Andrew

Author(s)A. Sauer1, A. Shively2

Author affiliation(s)Burns & McDonnell 1; Kansas City Water 2;

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Feb 2024

DOI10.2175/193864718825159262

Volume / Issue

Content sourceUtility Management Conference

Word count12

Modernizing Stormwater Design Criteria for Today's Multi-Benefit Solutions

Abstract

Stormwater design criteria have not been substantially updated since they were first established back in the 1950s. Most stormwater design manuals still reference those same criteria and event rainfall data from the 1961 Technical Paper No. 40, Rainfall Frequency Atlas of the United States. In urban areas we continue to apply these standards without thinking what it means or how it impacts our aging systems. We add on stormwater control measures as required as part of the post construction best management practices of the MS4 permit but those criteria are not integrated into the overall stormwater criteria. The results is an antiquated and outdated set of design standards that do not provide the functional value that the public is paying for. It is even more critical in this time when many cities want to improve the resiliency of urban areas in the face of climate change. However, do we have the criteria and tools to meet this need. Do we have the right design requirements that will result in the stormwater management outcomes that we desire. In Lawrence, Kansas these questions are being asked and evaluated using a city-wide watershed approach. 2D watershed models of all 59 watersheds are being developed to first fully understand the existing conditions and then to apply a range of potential rainfall events to determine what is the most cost-effective solutions. This is not a one size fits all approach but a watershed system approach that looks at what is the most optimal functional value in an area to reduce flooding, improve water quality, and protect public safety and property. This city-wide system multiple benefit approach is then being used to develop design criteria and stormwater management policy that will provide the highest value at the lowest cost. This approach is significantly different than blindly applying an assumed level of service design standard that would result in only larger and larger pipes or large underground storage. Using this approach, the City of Lawrence will develop a set of affordable solutions that will provide the greatest benefit across the watershed to maximize their available budget. This is in contrast to the past approach of designing a project to meet an outdated standard that was costly requiring it to be delayed for several years before it could be built leading to a back log of projects that would never be built. In Westport, Missouri, the oldest part of the City of Kansas City, Missouri, stormwater solutions have been designed to maximize the functional value within an available budget. This design was even more challenging because it was within a combined sewer system. A new design approach was therefore needed to address sever and frequent flooding, meet a federal combined sewer consent decree, and improve the business district. Several past studies had attempted to solve the problem using the old, antiquated design standards that resulted in over designed and unaffordable solutions that could not be built. Meanwhile the area still flooded almost every year impacting business, flooding cars, and causing public health issues given that the flood waters were combined sewer. Something had to change and that required a change in the design standards. Instead of meeting a 10-year level of service requirement the design focused on two recent real rainfall events along with a range of design events from the 2- to 10-year return frequency to establish the highest value solution for the budget. The resulting solution did not eliminate flooding but rather limited the flooding withing the public right of way at a depth and duration that was acceptable. This presentation will provide an overview of the current issues with design standards developed in the 1950s, ideas to improve them, and two case studies that will provide real examples of how and why we need to change. As cities strive to meet sustainability goals stormwater management must also be sustainable in the form of providing for adaptive designs that optimize the functional value at the most affordable price. Furthermore, if we start to consider stormwater as a resource rather than a waste our design objectives change from a drainage design standard to a water resource design standard. How will climate change impact us we really don't know but if we only require more and more conservative design that result in larger and larger pipes, we won't be creating more resilient cities we will only be creating larger uncontrolled conveyance system that impact our downstream neighbors. Resiliency means our design need to meet a range of potential future conditions not just one. Rainfall may get more intense and be of higher volume, but it also may be more time between events. We should be striving to create design standards that consider both outcomes so we can create more sustainable and resilient cities.

This paper was presented at the WEF Stormwater Summit, June 27-29, 2023.

SpeakerSauer, Andrew

Presentation time

11:15:00

11:45:00

Session time

10:45:00

12:15:00

SessionSession 10: Regulations, Policy, and Guidance

Session number10

Session locationKansas City Convention Center

TopicRegulation and Policy, Program Development, Management, Planning and Analysis