This is a preliminary program and is subject to change.
Tuesday, August 20, 9:45 a.m. ‒ 12:00 p.m.
STORMWATER INFRASTRUCTURE AND BMPs
B11 9:45 a.m. – 10:25 a.m.
Maintenance Inspection Program: Stormwater Management Facilities Over Time
Jason Schmidt, City of Portland, OR, Bureau of Environmental Services
The City of Portland’s Bureau of Environmental Services Maintenance Inspection Program conducts routine inspections on stormwater management facilities that are installed on private property. For nearly 10 years, this program has provided technical assistance and education to property owners, property managers, facilities managers, landscapers, and anyone else who may be responsible for the maintenance of their stormwater system. Facility types run the gamut of vegetated systems (ecoroofs, infiltration basins, planter boxes) and manufactured systems (StormFilters, hydrodynamic separators, sedimentation manholes). This presentation covers the structure of the program, permit requirements, a look into typical maintenance issues, how facilities change over the years, and recommendations for other municipalities seeking to introduce a maintenance inspection program of their own.
B12 10:30 a.m. – 11:10 a.m.
BMPs: It’s All in Vain If It’s Not Maintained
Pasquale Napolitano, Hydro International
One of the most commonly used terms in the stormwater industry is the acronym BMP—“best management practice”—used as shorthand for a structural control measure or device constructed or installed on a site to comply with stormwater regulations and permits. But the use of the acronym allows us to forget a key component of the term: “practice.” A BMP is commonly considered as a standalone or one-off measure or structure rather than as a practice that requires routine monitoring and intervention to ensure continual proper operation. And the reality is that once initial permits to build and occupy a space are achieved, BMPs are often forgotten. This presentation emphasizes that BMPs are practices that need to be continually maintained in order to function as intended; it includes checklists to increase monitoring compliance.
B13 11:15 a.m. – 11:55 a.m.
Managing a Successful Stormwater Planned Maintenance Program
Anna Griggs, Apex Companies LLC
The goal of this presentation is to show that through regular inspections and maintenance of the stormwater system, a property can maintain regulatory compliance as well as extend the life cycle of the system. In most cases an aggressive proactive maintenance and inspection plan will divert larger repair costs and help reverse the effects of poor or lack of minor repairs. In the long run, a properly managed maintenance and repair program reduces overall costs of the system. Real examples of progressive programs are provided, as well as the expensive results of neglecting the stormwater system compared to the costs of regular maintenance.
GREEN INFRASTRUCTURE I
G11 9:45 a.m. – 10:25 a.m.
Evaluating Stormwater Benefits of Atlanta’s Urban Forest System
Amanda Hallauer, City of Atlanta Department of Watershed Management
Eric Kuehler, US Forest Service
This presentation provides results of an urban forest assessment that uses the US Forest Service’s i-Tree model to calculate stormwater and other benefits of the City of Atlanta’s tree canopy and discusses how the Department of Watershed Management is using the model to evaluate and prioritize opportunities to preserve and restore forested land as a strategy to help meet triple-bottom-line goals of its green infrastructure program.
G12 10:30 a.m. – 11:10 a.m.
Trees and Water-Sensitive Urban Design
Matthew Werle, GreenBlue Urban
Urban trees can be an invaluable asset to cities. When designed correctly, tree planting can efficiently and sustainably assist in managing stormwater through the reduction of runoff and the improvement of water quality. But what are the key factors that must be considered to successfully integrate these beautiful elements into LID schemes?
G13 11:15 a.m. – 11:55 a.m.
Growing Green Infrastructure in Dayton Through Urban Gardens
Felicia Graham, City of Dayton, OH, Department of Water
The City of Dayton encourages green infrastructure through an Urban Agriculture Grant program. The goal of the program is to provide a citywide water-quality approach for capturing stormwater and increasing the quality of water that drains to its rivers and streams. In addition to supporting Dayton’s local food growers, the City also assists in providing water to tree farms. Grant applicants must ensure that erosion and stormwater capture practices are in place on site, and in return they receive assistance with installing water infrastructure to the site or paying for water use charges.
GREEN INFRASTRUCTURE II
G15 10:30 a.m. – 11:10 a.m.
From Stormwater BMP to a Wildlife Sanctuary: Success Through Many Stakeholders
Susan Rutherford, City of Atlanta
Lenny Tucciarone, City of Atlanta
Anwer Ahmed, Arcadis
A stream restoration project was constructed in 2013 and the stormwater treatment BMPs completed in 2015. Since its construction, the City of Atlanta has developed a management plan addressing the wetland and upland meadows, the ponds, invasive species control, mosquitoes, wildlife, and public access. The project has resulted in an area with diverse vegetation and aquatic life that has attracted wildlife that could not otherwise be conceived in a dense urban setting. Because of the City’s management efforts, several neighbors are now recognizing the community benefits the new greenspace can provide. The City intends to continue engaging community members through educational programs with partners like Atlanta Audubon and Trees Atlanta, as well as volunteer work days and tours, as a precursor to embarking on a formal plan for public access.
G16 11:15 a.m. – 11:55 a.m.
RiverSmart Homes: Best Management Practices and the Public
Kevin Newman, District of Columbia Department of Energy and Environment
Savannah Acosta, District of Columbia Department of Energy and Environment
RiverSmart Homes is an award-winning program administered by the District of Columbia’s Department of Energy and Environment since 2009, offering incentives to residents to reduce stormwater runoff from their properties. After signing up for the program via the internet or by phone, homeowners receive a stormwater site audit of their property to determine eligibility for subsidies to install one or more of the following BMPs: rain barrels, rain gardens or BayScaping, shade trees, permeable pavers, and revegetation. This presentation looks at the lessons learned throughout the history of the program, obstacles that homeowners often face, outreach efforts in underserved communities, and many other challenges and aspects of this program.
P11 9:45 a.m. – 10:25 a.m.
Countywide Watershed Management Strategies to Meet MS4 Permit Requirements
Jody Hughey, Arcadis
Todd Stevenson, Athens-Clarke County, GA
Eric Byrne, Tetra Tech
Athens-Clarke County, GA, is taking a proactive and progressive approach to manage and improve its watersheds and water resources to improve the quality of life for residents, provide a more resilient and sustainable community, and meet its MS4 NPDES permit requirements. Since 2010, Arcadis and Tetra Tech, in partnership with Athens-Clarke County, have produced several guidance documents and implemented countywide efforts to assess and improve the health of ACC’s rivers and streams in support of the countywide watershed improvement program. The work has led to development of an analytical process that informs the monitoring and characterization of watershed conditions. This includes the establishment of goals, objectives, indicators, and benchmarks for evaluating management needs and measuring success, and the identification and prioritization of management opportunities, including the use of hydrologic and water-quality models to assess structural best management practices.
P12 10:30 a.m. – 11:10 a.m.
Instituting a Structural Stormwater Control Permit Requirement in NPDES Phase I Stormwater Permits in Washington State
Douglas Howie, Washington State Department of Ecology
The Washington State Department of Ecology developed calculations to quantify the water-quality and flow-control benefits of proposed structural stormwater control projects such as installation of new BMPs or sweeping; permittees calculate “incentive points” for each project they can complete. This process allows Ecology and permittees to track the activities completed and to obtain similar levels of water-quality benefit from each permittee. Each permittee selects projects appropriate for their jurisdiction and reports the results in a standard format. Two key parts of this program are 1) the incentive point structure reflects the water-quality benefit, and 2) points are consistent between various project types. For example, the incentive points for street sweeping or installation of a runoff treatment BMP reflect the water-quality benefit obtained. This presentation discusses how the process operates, incentive point calculations, difficulties in establishing the process, and how the program may evolve during the permit term.
P13 11:15 a.m. – 11:55 a.m.
Common Pitfalls in Using Permit Language in Local Ordinances
Mary Halley, Wood
Many permitted MS4 communities opt to use language taken directly from their MS4 permit in their post-construction ordinances. This approach is understandable, as use of the permit language is and easy, low-cost way to ensure compliance with permit conditions. However, using MS4 permit language without further clarification by ordinance or policy can cause significant problems when the permittee must administer and enforce the ordinance. This presentation provides examples of MS4 permit language being used in local post-construction ordinances and the difficulties that result. With each example, the presentation will also provide ordinance or policy language to overcome these difficulties.
RESEARCH & TESTING
R11 9:45 a.m. – 10:25 a.m.
Using High-Resolution Experimental Rainfall-Runoff Data to Calibrate Existing Stormwater Management Models for Extensive Green Roofs
Oscar Warmerdam, Green Roof Specialty Products
Brad Garner, Green Roof Specialty Products
In this study, high-resolution experimental rainfall-runoff data from an advanced stormwater simulation laboratory are used to derive time of concentration estimates for several extensive green roof configurations incorporating a range of both common and novel materials. Accurate calibration of this critical hydrodynamic parameter across a range of green roof profile designs will improve dynamic performance modeling capabilities of existing SWM tools and allow stormwater engineers to more accurately predict long-term and event-specific hydrologic performance.
R12 10:30 a.m. – 11:10 a.m.
Automating the Process of Runoff Catchment Delineation for Hydrologic Modeling
Prasanna Dahal Jr., Arcadis US Inc.
This presentation introduces the approach used to create an ArcGIS tool that automates delineation of rainfall catchments, presents the theory behind rainfall runoff catchment delineation, talks about existing works and their limitations, and proposes solution to tackle the existing problems. A case study is presented to demonstrate the utility of the tool.
R13 11:15 a.m. – 11:55 a.m.
Accuracy of NRCS Runoff and Curvilinear Unit Hydrograph Approach for Estimating Peak Flow
William Gonwa, Milwaukee School of Engineering
This presentation shows calculation of curve number coefficients based upon NOAA Atlas 14 rainfall intensity estimates and peak discharge rates calibrated to flow rates determined from a 50 or more yearlong annual flood series. The calibrated values are compared with published values suggested by the NRCS in its National Engineering Handbook and checked to see if they remain constant as storm size changes. Both comparability and constancy are required for accuracy. The 11 rural watersheds located in the Midwest that were selected for assessment share characteristics of long-term consistency in land use, minimum storage, small watershed area, and 50 or more years of peak streamflow record.
Tuesday, August 20, 1:30 p.m. ‒ 3:00 p.m.
STORMWATER INFRASTRUCTURE AND BMPs
B21 1:30 p.m. – 2:10 p.m.
Adapting Stormwater Management for Coastal Floods
Douglas Marcy, National Oceanic and Atmospheric Administration
More frequent coastal flood events are posing a unique challenge to coastal communities. Inundation from high tides and storm surge can partially or completely submerge stormwater pipes and outfalls, causing backups that contribute to street-level flooding. Extreme rainfall and rising sea levels are increasing the frequency and duration of flood events in most coastal communities of the US, which is contributing to greater impacts to property values and infrastructure viability.
This presentation showcases the Adapting Stormwater Management for Coastal Floods, an interactive website that incorporates tools and methods to derive critical coastal water level thresholds and assess the potential impacts of threshold exceedance on stormwater infrastructure. Stormwater managers will come away with a better understanding of how they can work collaboratively with floodplain managers and planners in their communities to develop and implement plans that incorporate coastal flood mitigation and stormwater management goals.
B22 2:15 p.m. – 2:55 p.m.
Evaluating Old Urban Stormwater Models to Incorporate Updated Watershed Characteristics Subject to Climate and Land-Use Change Scenarios
Mehdi Ketabchy, Gannett Fleming Inc.
Hunter Loftin, Gannet Fleming Inc.
This presentation aims to evaluate old urban stormwater models to see which parameters essentially need to get updated. We assess the watershed response to future climate changes scenarios using the updated stormwater model in an ensemble framework approach. This study can benefit engineers and urban planners for two reasons: First, employing an ensemble approach provides robust estimates of climate change effects and their uncertainty by providing upper and lower bounds based upon a range of projected scenarios; these bounds can be further considered for infrastructures and BMP design. Second, the study can characterize the most significant parameters for those who aim to update old urban stormwater models.
GREEN INFRASTRUCTURE I
G21 1:30 p.m. – 2:10 p.m.
Building a Comprehensive Green Infrastructure Management Program Through Design, O&M, and Monitoring Plan Development
Mark Van Auken, Arcadis
Ruth Hocker, City of Lancaster, PA
This presentation provides detailed examples of the City of Lancaster’s green infrastructure design manual, operation and maintenance plan, and monitoring plan and explains how these program documents are assisting the City achieve its water-quality and compliance goals.
G22 2:15 p.m. – 2:55 p.m.
Implementing Atlanta’s Green Infrastructure Strategic Plan
Susan Rutherford, City of Atlanta Department of Watershed Management
The City of Atlanta Department of Watershed Management and its Green Infrastructure Task Force partners are implementing a strategic action plan to incorporate green infrastructure. At the same time, the City is undertaking integrated utility planning that is supported by its green infrastructure strategy, as well as watershed improvement projects, wastewater collection, and an Urban Waters Federal Partnership. This session explores key activities of these programs.
GREEN INFRASTRUCTURE II
G23 1:30 p.m. – 2:10 p.m.
Regenerative Stormwater Conveyance in Gwinnett County: Developing a Functional Educational Tool
Charles Crowell, Gwinnett Department of Water Resources
Elizabeth Gwinn, Tetra Tech Inc.
A regenerative stormwater conveyance system (RSC) is a series of pools, riffles, and cascades placed in a degraded drainage channel for the purpose of dissipating flow energy and encouraging infiltration through the use of engineered media. By mimicking natural stream and river formations, RSCs encourage revegetation and settling of suspended solids. In 2018 the Gwinnett County Department of Water Resources contracted Tetra Tech to complete design for a RSC located in Ronald Reagan Park, Lawrenceville, GA. This will be one of the first RSCs in Gwinnett County, and the first to be placed in a public park setting. Gwinnett County intends to use the constructed RSC to teach responsible stormwater management to the public and encourage land developers to implement them in future projects. The project faced numerous design challenges including a nearby sewer line, high public visibility, and limited space.
G24 2:15 p.m. – 2:55 p.m.
Leveraging Arts and Culture in Green Infrastructure: Lessons Learned in Atlanta and Chicago
Austin Robinson, Southface
Alex Trachtenberg, Southface
Anna Wolf, Center for Neighborhood Technology
Marcella Bondie Keenan, Center for Neighborhood Technology
This presentation highlights parallel programs in Atlanta, GA, and Chicago, IL, aimed at integrating community arts and culture in the implementation of green infrastructure in low-income and disinvested communities. The programs bolstered local workforce development opportunities, framed green infrastructure community benefits in meaningful ways to residents, and paired installations with community-driven art projects. The presentation reports on program successes and challenges and how both learned from each other through a cross-regional learning exchange.
P21 1:30 p.m. – 2:10 p.m.
Utilizing Asset Management Software for IDDE Tracking and Reporting
Melissa Ivancevich, City of Shoreline, WA
The City of Shoreline, WA, is using asset management software (Cityworks) to manage illicit discharge detection and elimination tracking and reporting, both for permit compliance and for interdepartmental coordination. This presentation shares the city’s experience in using Cityworks over the last five years to track and report IDDE, including saving time and resources and facilitating interdepartmental communication and coordination.
P22 2:15 p.m. – 2:55 p.m.
Adaptive Management of Municipal Catch Basin Cleaning Operations in the Digital Age
Christy Villa, Hoch Consulting
Genel Abordo, Hoch Consulting
Sinan Habeeb, Hoch Consulting
Faced with meeting sediment removal goals outlined by water quality improvement plans, the City of San Diego tasked Hoch Consulting and Tetra Tech with developing an optimized implementation plan for the city’s catch basin cleaning programs. This adaptive management plan blended mobile GIS technology with holistic prioritization strategies to achieve costs savings, increased crew productivity, and improved water quality citywide. Historic sediment removal trends and parallels were identified and used to develop prioritization strategies. Mobile GIS technology streamlined cleanings and allowed management to assign work based on the developed prioritization strategies. After one year of implementation, the plan resulted in an 82% increase in the volume of sediment removed and a reduction of 9,090 cleanings needed. As the plan evolves, additional long-term sediment deposition trends and optimization opportunities will become apparent.
RESEARCH AND TESTING
R21 1:30 p.m. – 2:10 p.m.
Workplan for Site-Scale Modeling and BMP Planning in San Antonio River Basin
Yu-Chun Su, LAN
Sheeba M. Thomas, San Antonio River Authority
Paul Hummel, RESPEC
The San Antonio River Authority has developed HSPF models and a suite of water-quality modeling tools to optimize BMP/LID implementation at sub-basin scale. A follow-up effort was to develop and test a workplan that involved site-scale modeling and BMP planning. The workplan includes a potential site-scale planning approach using the Gridded Surface/Subsurface Hydrologic Analysis (GSSHA) model, which will couple with the sub-basin-scale HSPF models. Another potential approach involved refining the HSPF models to allow site-scale modeling directly in HSPF. The target constituent is bacteria. This presentation covers the development of the site-scale modeling workplan, a comparison of the two proposed approaches, and the results of testing the approaches. The final workplan will allow agencies and communities to conduct BMP/LID planning and implementation at the neighborhood level.
R22 2:15 p.m. – 2:55 p.m.
Developing a Stormwater Control Measure Sizing Credit for the Infiltration Improvements Attributable to Plants
Scott Dierks, GEI Consultants Inc.
This presentation explores the relationship between plant species, their associated rooting patterns, and impacts to infiltration in rain gardens in southeast Michigan. The rain garden monitoring for this project uses both a novel, digital photographic monitoring technique and shallow wells to demonstrate that generally prairie plant species can easily double or triple initial or expected infiltration rates based on soil texture and long-established reference values. This work affirms that rooting patterns are integral to soil quality improvements, including infiltration. Our hypothesis is that any given soil’s maximum infiltration potential is best achieved with a mix of plants having complementary rooting patterns, including grasses, short and tall forbs, and woody plants. The monitoring for this project was conducted in rain gardens in Washtenaw County, MI. With this work, the county is considering the creation of a sizing credit for well-maintained rain gardens that retain their target prairie plant species over time.
Tuesday, August 20, 3:30 p.m. ‒ 5:00 p.m.
STORMWATER INFRASTRUCTURE AND BMPs
B31 3:30 p.m. – 4:10 p.m.
How to Streamline Green Infrastructure and Stormwater BMP Design for Transportation Projects:
Anwer Ahmed, Arcadis
Rich Greuel, Arcadis
Brad McManus, Georgia Department of Transportation
This presentation focuses on the Georgia Department of Transportation’s efforts to develop policies, standards, procedures, and tools to implement LID and green infrastructure to meet the water-quality and runoff reduction requirements in the 2017 MS4 permit and also considers the long-term operation and maintenance of the BMPs. Discussion includes the policy for siting and evaluating green infrastructure, GDOT’s drainage design manual, standardized design process including construction details for the BMPs, digital design tools for infrastructure sizing, and consideration of maintenance in the design process. The presentation includes overview of these tools as well as the lessons learned in developing the policies and procedures that will be helpful to other MS4s in incorporating water-quality and runoff reduction in their green infrastructure programs for linear transportation systems.
B32 4:15 p.m. – 4:55 p.m.
Interconnecting Stormwater Models to Analyze Complex Drainage Systems for Large Infrastructure Projects
Dmitrijs Obolevics, Arup
This presentation explains how three software packages were leveraged to simplify the design of a large, complex stormwater network for the New International Airport of Mexico City. The project included several gravity systems, 10 pump stations, two lift stations, and two force mains. Breaking down the network into pieces allowed for a simplified and expedient approach to analyzing the stormwater network.
G31 3:30 p.m. – 4:10 p.m.
Green Infrastructure Use for Watershed Resiliency: Rainwater/Stormwater Harvesting for Beneficial Uses
Neal Shapiro, City of Santa Monica
This presentation looks at how the City of Santa Monica uses innovative rainwater/stormwater harvesting, low impact development, and green infrastructure strategies to manage precipitation locally to improve water quality and increase local water supply.
G32 4:15 p.m. – 4:55 p.m.
Where Water Falls: Place-Based Treatment of Water Where It Falls
Joanne Rodriguez, GreenStructure Ltd.
Mary Ann Uhlmann, Urban Horticulture Consulting
Given the current climate predications that increasing and severe weather events will become the new norm, how do we design our cities to become more water-capturing like a “sponge” city? Years of development have stripped away vital ecosystem services and have given way to more gray infrastructure development. With the United Nations, the World Health Organization, the Centers for Disease Control, and other NGOs examining the need to deploy ecosystem services—and with the need to meet EPA’s nonpoint-source pollution requirements—how do we integrate green infrastructure design into the existing built environment as a means to treat water where it falls? Doing so will give cities greater use of financial resources, start to shift the burden of stormwater management, and result in a resilient future.
P31 3:30 p.m. – 4:10 p.m.
Continuous Water-Quality Monitoring Data: A Complete Data Set
Ben Hammond, Woolpert Inc.
Jon Batson, Anderson County, SC
Tim Sherbert, Spartanburg County, SC
With the prevalence of water-quality monitoring equipment, communities and organizations are collecting more data than ever. What can or should be done with all this data? How do you manage this much data? How are data checked for quality control? Are the data corrected? What will the data be used for? Do the data drive other decisions? Who else uses the data? The end use of the data drives some decisions, while the budget may still be the deciding factor. The answer to these and other questions surrounding a complete data set will be evaluated and examples will be presented from several Upstate South Carolina communities.
P32 4:15 p.m. – 4:55 p.m.
Basic Sampling Techniques, Explained and Simplified
John Cummings, NV5 Inc.
This presentation is designed to explain and simplify the basic sampling techniques used for wastewater, drinking water, stowmwater, surface water, and groundwater. We’ll start at the beginning by identifying the objective to the sampling event. Even if the answer is obvious (regulatory compliance), there’s always a root cause, and understanding the reason is often the key to understanding everything that comes next. The more you know about the why, the better you’ll be at doing the how. Using demonstrations, we’ll look at the differences between sampling methods such as flow proportional composite samples, grab samples, time composite samples, and, equally important, when not to take samples. We’ll discuss bottles types and bottle selection for the type of samples (i.e., a 40 ml amber vial with septa lid should be used for VOC sampling rather than a plastic bottle).
FUNDING, STAFFING, AND MANAGING
S31 3:30 p.m. – 4:10 p.m.
US Department of Agriculture Funding for Stormwater Infrastructure Projects in Small and Rural Communities
Valdis Krumins, USDA Rural Utilities Service
Lorrie Davis, USDA Rural Utilities Service
Steve Polacek, USDA Rural Utilities Service
The US Department of Agriculture Rural Development, Rural Utilities Service, Water and Environmental Programs (WEP) provides affordable financing for water and waste projects to improve the quality of life in rural communities. In a typical year, WEP provides about $1.5 billion in loans and grants for water and waste infrastructure; in fiscal year 2018, more than $4 billion was made available. While the majority of these funds have traditionally been used for drinking water and wastewater, they can also be used for new stormwater projects, stormwater infrastructure rehabilitation, green infrastructure, and sewer separation.
S32 4:15 p.m. – 4:55 p.m.
The Onondaga County Save the Rain Program: Maximizing Environmental Benefit of CSO Reduction With Budget Constraints
Zachary Monge, Jacobs
This presentation focuses on how the county has adapted its program to reduce combined sewer overflows while facing budget constraints, including case studies from specific projects. Key subjects include the cost effectiveness of various types of green infrastructure (porous pavements, bioretention, underground infiltration, green roofs); strategies to maximize the available budget (partnership projects, integrated planning, public-private partnerships); alternative funding sources; planning tools; and siting considerations.
RESEARCH & TESTING
R31 3:30 p.m. – 4:10 p.m.
Data-Driven Management Decisions to Address a Fecal Coliform Impairment in the May River, Bluffton, SC
Beth Lewis, Town of Bluffton, SC
Following rapid development within the May River Watershed, rising fecal coliform levels in the river’s headwaters resulted in a shellfish harvesting closure in 2009. The Town of Bluffton coordinated a proactive approach to the problem through the May River Watershed Action Plan. Following an adaptive management approach, the plan provides strategies for assessing problems and directing resources to implement solutions based upon the town’s water-quality monitoring data. Employing this approach has guided the town’s management decisions to construct a stormwater pond, initiate a microbial source tracking program, prioritize sewer extension, and develop a financial incentive program to assist with individual sewer connections to eliminate septic systems as a confirmed source of fecal coliform pollution. This presentation highlights how an adaptive management approach and data-driven management decisions can be made at the municipal level to address a water-quality impairment.
R32 4:15 p.m. – 4:55 p.m.
Phosphorus Removal in Stormwater by Electrocoagulation
Jong-Yeop Kim, Florida Gulf Coast University
Phosphorus (P) impairment of surface waters remains a major water-quality concern in the US and worldwide. This study examines the effects of treatment parameters (pH, conductivity, current density, initial concentration of P, and type of electrode) on the performance of the electrocoagulation (EC) process and evaluates the required electrical energy consumption rate and reaction time to achieve 90% of conversion. Since the P removal mechanism in EC is largely dependent upon electro-chemical precipitation, slow sand filtration was designed and implemented as a post-treatment process after EC for the complete removal of P-metal precipitants from water source. An initial P of 2 mg/L was completely removed in less than 50 minutes by EC with aluminum electrode, while iron electrodes consistently showed lower removal efficiency. The removal efficiency was demonstrated to be directly proportional to the conductivity and power supplied.
Wednesday, August 21, 8:30 a.m. ‒ 10:00 a.m.
STORMWATER INFRASTRUCTURE AND BMPs
B41 8:30 a.m. – 9:10 a.m.
Lake Smith Weir, Concept to Completion: Hazard Classification Opinion Analysis and Construction Issues
Seshadri Iyer, AECOM
Michael Mundy, City of Virginia Beach, VA
This project was initiated to build a 70-foot-long concrete weir. A concrete sheet pile weir containment structure is being built around the upstream end of the outlet culvert. During construction, unforeseen riprap fill was found in the lake bottom, preventing the sheet pile placement by jetting. Temporary sheet piles were driven and exploratory dredging was done to identify and quantify the obstruction material. During these activities, soil separation in the embankment along Northampton Boulevard was reported. Final construction success depends on being aware of unforeseen conditions and being able to respond and adjust appropriately.
B42 9:15 a.m. – 9:55 a.m.
Improving Atlanta’s Dean Rusk Park Through Green Infrastructure and Adaptive Controls
Matthew Jones, Hazen and Sawyer
Dayton Marchese, Opti
Dean Rusk Park in Atlanta features a pond managing an urban watershed where trash and sediment are regular challenges. Improvements designed for the park to address these issues include a floating wetland trash boom, subsurface pretreatment, adaptive control of the pond outlet structure, implementation of green infrastructure, and remedies to noted deficiencies around the park. The improvements developed for Dean Rusk Park are expected to provide localized benefits as well as an example of how existing detention ponds can be enhanced through the use of adaptive and sustainable design elements that improve stormwater quantity and quality control along with aesthetics and community benefits.
G41 8:30 a.m. – 9:10 a.m.
Retrofitting New York City Public Properties With Green Infrastructure
Swati Kalia, Arup
Eme Williams-Blake, Arup
The New York City Department of Environmental Protection has implemented a right-of-way green infrastructure program to help meet its 2030 CSO reduction target. However, the program’s progression has shown that a significant number of proposed sites must be rejected due to siting constraints. This has led DEP to supplement the program with onsite green infrastructure on public properties such as parks, schools, and public housing. This presentation describes Arup’s approach to onsite green infrastructure design, including siting, choosing the type of green infrastructure practice, best methods for stormwater interception, and how green infrastructure can improve the site’s functionality. It will also detail the methodology chosen to analyze peak flows and drain down times in detention practices and inform on how NYC is tackling poor soil infiltration to reach the CSO reduction goals and co-benefit existing public properties through the implementation of green infrastructure.
G42 9:15 a.m. – 9:55 a.m.
Retrofitting Roadways With Permeable Pavers in Atlanta
Cory Rayburn, City of Atlanta, GA
The City of Atlanta has constructed one of the largest roadway retrofit projects using permeable pavers known to date. Permeable paver systems are typically installed in parking lots; however, with limited publicly owned property within the flood-prone neighborhoods of Peoplestown, Mechanicsville, and Summerhill, the City turned to the right of way for much-needed flood relief. The City completed the installation of four miles of permeable paver roadways coupled with 32 stormwater planters in September 2016.
P41 8:30 a.m. – 9:10 a.m.
Enhancing Water Quality Through Bacteria Watershed Action Plans
Angela Vandelay, Wood Environment and Infrastructure Solutions Inc.
As MS4 permits are becoming more stringent, municipalities are being tasked with the new requirement to develop watershed action plans (TMDL implementation plans) to address total maximum daily load requirements. This presentation explores some of the challenges MS4s encounter in addressing their contribution to bacteria impairments in TMDL watersheds and discusses a variety of programmatic BMPs that municipalities may consider for the cost-effective initial steps of implementation of their bacteria TMDL plans.
P42 9:15 a.m. – 9:55 a.m.
An E. coli TMDL: Now What?
Brian Behrens, Woolpert Inc.
Tim Sherbert, Spartanburg County, SC
Jon Batson, Anderson County, SC
What do you do when your organization is faced with dealing with a bacteria TMDL? Come hear how several municipalities in Upstate South Carolina are working to evaluate their responsibilities.
FUNDING, STAFFING, AND MANAGING
S41 8:30 a.m. – 9:10 a.m.
Leveraging Technology and Policy to Create a Defensible Capital Improvement Program
Richard Greuel, Arcadis
Jill Bazinett, City of Alpharetta, GA
Today’s municipal stormwater program managers face challenges to allocate limited resources and manage a drainage system that is aging and in need of improvement and repair. Alpharetta, GA, a community just north of Atlanta, has developed a program that manages its stormwater infrastructure maintenance through the use of appropriate technology and policy development. This presentation discusses Alpharetta’s program and how policy and technology helps make logical and defensible decisions on allocating resources to capital improvement projects.
S42 9:15 a.m. – 9:55 a.m.
Evaluating Funding Options for the Village of Wilmette’s Stormwater Capital Improvement Program
Jill Wu, Raftelis Financial Consultants
Keith Readling, Raftelis Financial Consultants
Brigitte Berger-Raish, Village of Wilmette, IL
The Village of Wilmette seeks to modernize its stormwater infrastructure to provide 10-year flood protection to residents. The Village developed several options for alleviating flooding and is preparing to move forward with constructing neighborhood stormwater storage improvements, with an estimated cost ranging from $48 million to $55 million. Historically, the Village has funded stormwater improvements through a sewer fee tied to water consumption; it is currently working with Raftelis to analyze the feasibility of implementing a stormwater fee versus a wastewater rate increase. By attending this session, participants will learn how to develop a framework for analyzing the options of funding improvements with a stormwater fee versus a sewer user fee, how to consider structuring fees for each option, and how to compare the resulting customer impacts of each option.
INDUSTRIAL STORMWATER MANAGEMENT
D41 8:30 a.m. – 9:10 a.m.
BMP Strategies, Selection, and Implementation at NPDES-Regulated Industrial Stormwater Facilities: A Tiered Approach for an Increased Regulatory Compliance Trajectory
Jonathan Meronek, SCS Engineers
Under the Clean Water Act, stormwater regulation is growing, evolving and becoming more robust, with increased compliance standards. For the stormwater managers, consultants, and dischargers, the stakes have never been higher.
For many industrial dischargers, it is no longer viable to adhere to status quo BMPs. In many cases, it is more feasible to approach escalating regulatory compliance with an eye to the future, by thoughtfully seeking long-term and sustainable solutions. This presentation shows the challenges of the industrial regulations and associated escalation scenarios, and reviews compliance numbers for the dischargers seen as “case studies” for emerging regulatory trends.
D42 9:15 a.m. – 9:55 a.m.
Tackling Industrial Stormwater Compliance in the Chattahoochee River Watershed
Jessica Sterling, Chattahoochee Riverkeeper
Jason Ulseth, Chattahoochee Riverkeeper
Controlling industrial stormwater runoff is a daunting challenge throughout the Chattahoochee River basin in Georgia. The Georgia Environmental Protection Division issues the Georgia Industrial General Permit (IGP) that regulates more than 2,000 facilities across the state. Unfortunately, the state agency does not have the resources to identify industries that do not have coverage under the IGP but are required to. Since 2012, Chattahoochee Riverkeeper has investigated 400 industrial facilities located in the Chattahoochee River watershed and worked individually with 120 facilities to bring them into compliance with the IGP. In this presentation, Chattahoochee Riverkeeper will present a series of case studies demonstrating methods used in finding non-compliant industrial facilities and how they worked with each industrial facility to develop stormwater pollution prevention plans, implement best management practices, and monitor water quality.
Wednesday, August 21, 10:30 a.m. ‒ 12:00 p.m.
STORMWATER INFRASTRUCTURE AND BMPs
B51 10:30 a.m. – 11:10 a.m.
Stormwater Modeling Done Right
Douglas Beyerlein, Clear Creek Solutions Inc.
Joseph Brascher, Clear Creek Solutions Inc.
The appropriate design of stormwater facilities for both flow control and water quality requires accurate stormwater modeling. Traditional stormwater modeling has used simple computational methods originally developed based on the limitations of slide rule calculations. These simple methods are not appropriate for today’s stormwater design. A better solution is to take advantage of EPA’s HSPF and SWMM software. HSPF’s hydrology and water-quality continuous simulation algorithms accurately simulate rainfall-to-runoff processes. SWMM’s sophisticated hydraulic dynamic wave equations accurately model stormwater conveyance features. Together, HSPF and SWMM provide the tools to model stormwater accurately and realistically. This presentation demonstrates the value of combining HSPF and SWMM and discusses issues related to the linkage of the two modeling packages. Examples of how this combination of packages have been used will be presented.
B52 11:15 a.m. – 11:55 a.m.
Developing a Proactive Risk of Failure Analysis to Drive a Stormwater Inspection Program for the City of San Antonio
Noelle Gaspard, RJN Group
Aging stormwater infrastructure is one of the biggest challenges facing communities today. With portions of the City of San Antonio’s stormwater collection system approaching 100 years old, a comprehensive understanding of the condition and location of the existing system was needed. This presentation provides an overview of the multi-year stormwater system televising, mapping and condition assessment project the city initiated in 2015, the development stormwater CCTV master plan, and information about technologies used to complete the project, including mobile LiDAR for above-ground survey and InfoMaster Sewer to transform asset condition data and defect codes into GIS.
G51 10:30 a.m. – 11:10 a.m.
Adapting Green Infrastructure Tracking, Design, and Evaluation Methods for a Variety of Program Goals
Alysondria Eason, Hazen and Sawyer
Across variable drivers and program scales, there are common strategies for green infrastructure opportunity tracking, design, and program evaluation that can be adapted to meet various needs and objectives. While some of these programmatic elements are necessities in large-scale urban programs, they also offer distinct benefits when adapted to smaller-scale green infrastructure implementation efforts. Tracking stormwater opportunities and constraints, standardizing designs, and evaluating programmatic goals using interactive dashboards are some of the methods that can be scaled according to program size. It is important to understand that not every strategy is needed or cost-effective for every municipality without adaptation. With appropriate adjustments, it is often possible for smaller-scale initiatives to benefit from the efficiencies and lessons learned from larger programs, supporting the realization of green infrastructure benefits across a wide array of program drivers and implementation scales.
G52 11:15 a.m. – 11:55 a.m.
Monitoring the Effectiveness of Green Infrastructure
Lara Kurtz, AKRF
Green infrastructure designs implemented by public entities for managing right-of-way runoff are often constrained within the public right of way or require large amounts of site prep and excavation. A utility of stormwater forest BMP as a viable, cost-effective alternative for managing public right-of-way runoff provides a viable solution to address these problems. Stormwater forest BMPs offer a shallow footprint alternative that can be implemented quickly on undervalued land, utilizing fast-growing trees as the primary stormwater volume reduction mechanism. This presentation demonstrates performance monitoring of this type of installed practice.
P51 10:30 a.m. – 11:10 a.m.
The District of Columbia’s Pollution Prevention Plan for Municipal Facilities
Clara Elias, District of Columbia Department of Energy and Environment
This presentation discusses the stormwater pollution prevention plan the District of Columbia’s Department of Energy and Environment (DOEE) created to bring municipal facilities into compliance with stormwater regulations within two years, by July 2020. The program plan combines online resource management systems, education, and coordination to see improvements in good housekeeping and permit compliance. DOEE will provide an overview of the plan and share successes, challenges, and lessons learned after one year of implementation.
P52 11:15 a.m. – 11:55 a.m.
From West to East: NPDES Trends From the Left Coast
Sean Porter, Apex Companies LLC
Coming to a watershed near you… This presentation focuses on several new trends with NPDES stormwater permits in the West. From California with the inclusion of numeric effluent limits to the new Oregon 1200z industrial permit, Sean Porter will present an overview of the new requirements, recent court decisions, electronic reporting, certifications, and inclusion of total maximum daily loads (TMDLs).
FUNDING, STAFFING, AND MANAGING
S51 10:30 a.m. – 11:10 a.m.
Lessons From 45 Years of Stormwater Management
Andrew Reese, Wood
Stormwater management, from its beginnings as agricultural drainage gone urban to its present highly technical and specialized set of skills and practices, has undergone many transitions and has many more to face. All practitioners have both a duty to understand the history of mistakes and corrections, and the responsibility and opportunity to use their creative imagination and specialized skills to improve not only their little corner of the globe, but to contribute to the flow of science, ideas, and hard sleeves-rolled-up work—pushing their pieces of the puzzle to the center so the full picture can emerge.
S52 11:15 a.m. – 11:55 a.m.
Atlanta’s Water Equity Roadmap
Todd Hill, Atlanta Department of Watershed Management
Darryl Haddock, West Atlanta Watershed Alliance
The City of Atlanta Department of Watershed Management is participating with community stakeholders in a Water Equity Task Force to better understand the impacts of public infrastructure investments and affordability. The task force has developed a Water Equity Roadmap to address issues facing vulnerable communities in Atlanta. This presentation reviews the roadmap, defines what water equity means for the field of stormwater management, examines the issues facing Atlanta neighborhoods, and highlight tangible strategies the task force is taking to address the focus areas of workforce development, community benefits, and affordability.
INDUSTRIAL STORMWATER MANAGEMENT
D51 10:30 a.m. – 11:10 a.m.
Industrial Stormwater Treatment as Early Action Initiatives on Superfund Sites
Nathan Holloway, Clear Water Services LLC
This presentation focuses on two case studies of industrial facilities located along impaired water bodies that are in the early action phases of Superfund Cleanup. They are using active treatment systems to comply with stringent water-quality regulations associated with early action cleanup initiatives. The case studies will contrast one site that has been complying with these regulations for several years with another that has just implemented treatment to discuss how lessons learned were applied and how early action initiatives for source control can be met on other similar sites.
D52 11:15 a.m. – 11:55 p.m.
Minnesota’s Experience With Coal-Tar Sealants and PAHs in Stormwater Ponds
Early in 2019, seven Minnesota cities filed lawsuits seeking damages from the refiners of coal-tar sealants for damages those products have caused, specifically the contamination of stormwater pond sediments. When contamination levels exceed state regulatory thresholds for polycyclic aromatic hydrocarbons (PAHs), pond dredgings must be transported to and disposed of at lined landfills. The Minnesota Pollution Control Agency estimated the additional costs for the owner/operators of stormwater ponds in Minnesota to be in the range of $1 to $5 billion. This presentation examines the implications for stormwater managers of these lawsuits.
Wednesday, August 21, 1:30 p.m. ‒ 3:00 p.m.
STORMWATER INFRASTRUCTURE AND BMPs
B61 1:30 p.m. – 2:10 p.m.
Score! Towson University Rehabilitates Large-Diameter CMP Directly Under Football Stadium
Tom Perry, Multi Utilities Ventures
Joe Cherry, AP/M Permaform
After a 100-foot section of 72-inch corrugated metal storm pipe collapsed just upstream of Towson University’s Johnny Unitas Stadium and the affected pipe was replaced with open-cut, the university completed a full system inspection and identified about 1,000 feet of nearly failing pipe downstream, directly underneath the stadium. The university sought a trenchless option that would not compromise flow capacity and could be installed in long stretches of pipe with limited access. Among the solutions considered were cured-in-place pipe, sliplining, and centrifugally cast concrete pipe, which was the option eventually chosen. Details and challenges of the project are discussed.
B62 2:15 p.m. – 2:55 p.m.
Systematic Design of Sponge City Construction in Beijing, China
Yongwei Gong, Beijing University of Civil Engineering and Architecture
Jianlong Wang, Beijing University of Civil Engineering and Architecture
China has started pilot construction of the sponge city, aiming to comprehensively improve urban water ecology, the water environment, and water safety problems. This research proposed a comprehensive, systematic, and implementable sponge city construction project based in Beijing, China. It is expected that the capture ratio of total annual runoff volume, nonpoint-source pollution control rate, rainwater resource utilization rate, and CSO frequency are more than 80%, 43%, 3%, and less than four times per year, respectively.
G61 1:30 p.m. – 2:10 p.m.
Modeling of Green Infrastructure Practices
Dmitrijs Obolevics, Ove Arup and Partners PC
Swati Kalia, Ove Arup and Partners PC
This presentation covers a research study undertaken to explore and identify the best approach to represent green infrastructure practices within a dynamic hydraulic simulation model. The modeling approach is based on the research conducted based on four hydraulic modeling tools: Infoworks ICM (Integrated Catchment Modeling), EPASWMM (Storm Water Management Model), XPDrainage, and Storm and Sanitary Analysis. The existing onsite green infrastructure project with New York City Department of Environment (NYCDEP) was used as a pilot area for this study. The site is an existing playground where NYC DEP wants to implement a number of green infrastructure practices as part of its CSO reduction program. The research study included modeling of green infrastructure practices such as permeable pavements and rain gardens proposed as part of the project.
G62 2:15 p.m. – 2:55 p.m.
Sustainable Design and the Evolving Standard of Care
Jean Terry, Manion Stigger LLP
This presentation discusses the legal implications of green infrastructure—in particular, how “green” practices can affect the professional liability for engineers and other building professionals and how to safeguard against that liability. The presentation will also review the impacts green infrastructure can and will have on our current system of design and construction.
P61 1:30 p.m. – 2:10 p.m.
Green Infrastructure Bioswale BMP Performance Demonstration Project in Harris County, TX
Yu-Chun Su, LAN
Roberto J. Vega III, Harris County Flood Control District
This presentation covers the BMP Performance Demonstration Project for evaluating the effectiveness and practicability of modifying HCFCD backslope drainage systems into a bioswale BMP. The project included two selected sites, with two outfall corrugated metal pipes included at each site. The drainage area to one of the pipes was maintained as the control while the other was revised to a bioswale BMP. A monitoring plan and quality assurance project plan were developed to define requirements for evaluating the effectiveness of bioswale BMP. A creative flow measurement methodology using aluminum portable weir plates was developed and field-tested. Stage-discharge rating curves were developed using weir equation together with linear regression and non-linear optimization techniques. Ambient water-quality data from the Harris County Flood Control District’s inline detention basins with wetlands, and the design of the basin, will also be presented.
P62 2:15 p.m. – 2:55 p.m.
City of Calgary Stormwater Loading Targets Development
Stacey Zhao, City of Calgary, AB
To control total suspended solids and total phosphorous loadings to Bow River and meet the city’s total loading management objectives from Alberta Environment and Parks, the City of Calgary developed citywide stormwater loading targets for each subwatershed using a calibrated SWMM-SUSTAIN model framework. This presentation discusses the model, monitoring, and results.
FUNDING, STAFFING, AND MANAGING
S61 1:30 p.m. – 2:10 p.m.
Watershed-Wide NPDES Permits: Conflict, Communication, and Consensus
Heather Merenda, City of Santa Clara, CA
Managing monitoring, TMDLs, and other projects is challenging even within your own organization, let alone cooperating with other entities. The Los Angeles NPDES permit allows for watershed-based approaches for compliance. This presentation provides lessons learned for managing conflict, communication issues, and collaboration. It also includes discussion of the “no deal” elements and how to divide what’s possible with the watershed versus what may be needed to go it alone.
S62 2:15 p.m. – 2:55 p.m.
Tools for Tracking Multiple NPDES Properties at the Port of Los Angeles
Rachel McPherson, Port of Los Angeles
Jason Locklin, CloudCompli
The Port of Los Angeles encompasses 7,500 acres, covers 43 miles of waterfront, and is a landlord port supporting a multitude of industries, commercial enterprises, and entertainment. Operated by the City of Los Angeles Harbor Department, the Port receives discharges from upstream, near-shore, and on-water activities. As a responsible party in the Greater Harbor Toxics TMDL and the Inner Cabrillo Beach Bacteria TMDL, the Port is active in research, prevention, and compliance activities. Through collaboration with CloudCompli software, the Port is able to manage the variety of NPDES permit requirements both within the department and for tenant outreach efforts.
INDUSTRIAL STORMWATER MANAGEMENT
D61 1:30 p.m. – 2:10 p.m.
Water Management on a Solid Waste Facility
Kristine Sommer, Clear Water Services LLC
This presentation focuses on a waste facility historically known for contaminated subsurface conditions while bordering an impaired waterway in Seattle, WA. The facility was required to install two water treatment systems, one for contaminated barge decant water and one for industrial stormwater runoff treatment. As the treatment systems process two different types of water, each is regulated by a different agency and has different design and discharge criteria. This presentation examines how the facility was able to maintain compliance under two different water discharge permits and manage stormwater, process water, and contaminated groundwater while also completing large utility and infrastructure upgrades in support of two new water treatment system installations.
D62 2:15 p.m. – 2:55 p.m.
Is Your Roof Providing More Than Shelter? Treating Industrial Roof Runoff
Paul Eger, Global Minerals Engineering
An industrial facility was out of compliance with its stormwater permit. Despite an end-of-pipe treatment system, zinc exceed the 0.117 mg/L benchmark, which triggered enforcement action. To avoid costly retrofits and expansion of the treatment system, a site evaluation was conducted. A warehouse extension with a galvanized roof was only 6% of the total site but contributed 40% of the zinc. An innovative low-cost method, an upflow drum filter (UDF), using peat sorption media and 55-gallon drums, was developed to treat roof runoff. The UDFs initially removed over 90% of the zinc, but removal slowly decreased. By replacing the media every six months, high removal was maintained. UDFs reduced overall zinc loading to the treatment system by 50%, and benchmarks were met.
Wednesday, August 21, 3:30 p.m. ‒ 5:00 p.m.
STORMWATER INFRASTRUCTURE AND BMPs
B71 3:30 p.m. – 4:10 p.m.
Expanding Asset Protection to Include Stream Restoration
Joel McSwain, Hazen and Sawyer
As urban streams degrade and threaten sanitary assets, the protection of the assets is often seen as a more immediate need than stabilizing the impaired stream that is the cause. Site evaluations commonly arrive at the question of spot repair and localized hard-armoring versus addressing the reason for stream instability. Because threatened assets often appear one at a time, it can be difficult to justify larger and more expensive stream restoration solutions. There are, however, clear benefits to providing a more holistic solution. This presentation focuses on reasons to consider protection of assets and stream restoration together and includes tools to evaluate and communicate information to support the combined approach. Examples will be shown of how the need for asset protection can be used as an opportunity to evaluate surrounding stream conditions to best determine the most effective locations and approaches.
B72 4:15 p.m. – 4:55 p.m.
Going With the Flow: The Benefits and Challenges of Stream Restoration Projects in Achieving Restoration Goals
Chris French, Bio Clean Environmental
This presentation discusses the benefits and challenges associated with streambank restoration projects and covers the variety of goals that need to be considered when deliberating high-expense projects. It will provide an overview of peer-reviewed literature on the topic, highlight case studies, and discuss uncertainties associated with assigning pollution reduction credits on potentially high-risk conservation and restoration projects.
G72 3:30 p.m. – 4:10 p.m.
Integrating Green Infrastructure Into Nonpoint-Source and Stormwater Management in Georgia
Christine McKay, US EPA
Since the early 2000s, Georgia has made considerable progress in implementing green infrastructure practices holistically at the site, neighborhood, and landscape/watershed scales by engaging local governments in its adoption. This presentation describes these practices and their benefits, offers an overview of Georgia’s nonpoint source program activities on green infrastructure, and provides examples of how green infrastructure BMPs are included in the state’s restoration and healthy watershed management plans.
G74 4:15 p.m. – 4:55 p.m.
A Holistic Approach to Stormwater Management in Los Angeles: What Does That Look Like?
Mark Van Auken, Arcadis
Khaled Abdo, Arcadis
Kelsey Jessup, The Nature Conservancy
This presentation focuses on the collaboration between The Nature Conservancy and Arcadis on a project that is evaluating benefits from stormwater management in addition to water quality and quantity from a regional perspective to better understand and advocate for Los Angeles County-wide policies that prioritize and support nature-based solutions. The work involves desktop analysis of landscape-scale (watershed-wide) and project-specific attributes using a GIS-based model that reflects the County’s Safe Clean Water Program goals and project scoring criteria.
P71 3:30 p.m. – 4:10 p.m.
Saving Time and Cost Through an Umbrella Pollution Prevention Plan
Richrd Greuel, Arcadis
Developing stormwater pollution prevention plans (SWPPPs) for operators with multiple facilities and types can be time consuming. Creating an umbrella document providing a comprehensive overview of all facility types and pollution prevention control measures can guide and significantly reduce the effort, time, and cost to prepare site-specific SWPPPs.
P72 4:15 p.m. – 4:55 p.m.
Silt Fence Rules of Thumb: Guiding or Misguided?
J.P. Johns, Woolpert
Jackie Williams, South Carolina Department of Transportation
Silt fence is used for nearly every construction project, but its design and installation is largely based on rules of thumb. The South Carolina Department of Transportation performed an in-depth analysis of traditional rules of thumb to determine their validity. The 100-foot slope length, 0.25-acre, 0.25 cubic feet per second, 80% total suspended solids trapping, and more were evaluated using hydrologic modeling, design aids, sediment calculations, and statewide soil data. This presentation explores the analysis process and facilitates open discussion about this popular best management practice.
FUNDING, STAFFING, AND MANAGING
S71 3:30 p.m. – 4:10 p.m.
Atlanta’s Environmental Impact Bond for Green Infrastructure
Glen Behrend, Atlanta Department of Watershed Management
David Bell, Jacobs Engineering Services
This overview of Atlanta’s Environmental Impact Bond for green infrastructure within the Proctor Creek Watershed discusses the selection of stormwater volume as a proxy for environmental performance across projects, tiered financing models, the development of a probability model for prediction of project success, lessons learned, and opportunities for future refinement.
S72 4:15 p.m. – 4:55 p.m.
Stormwater Funding Review for the Unified Government of Athens-Clarke County, GA
Kyle Stevens, Stantec Consulting Services
Todd Stevenson, Athens-Clarke County
In 2005 a stormwater funding strategy consisting of a special purpose local-option sales tax, development fees, and a stormwater fee was implemented in Athens-Clarke County. An audit conducted in 2015 and 2016 resulted in fee increases to thousands of stormwater customers. At the same time, a bill introduced in the Georgia State legislature would have exempted “water neutral” parcels from the stormwater fee. Stantec was chosen to assist the county with a review of the overall funding strategy and the stormwater fee in particular. As the study progressed it became clear that many corrugated metal pipes were reaching the end of their lifespans. An increase in the fee was considered to handle these capital needs. This expanded the scope of the public relations campaign in a compressed time frame.