The Calm Before the Storm: Proactive I/I Remediation in Brevard County, FL

The Calm Before the Storm: Proactive I/I Remediation in Brevard County, FLAbstractBrevard County, situated on the East Central coast, is home to over 600k individuals. It encompasses sixteen municipalities including Cocoa Beach and Cape Canaveral. The latter serves both cruise ships as well as the Space Force Station and Kennedy Space Center. Brevard is also home to over 250sq miles of wildlife refuges which sit alongside the Indian River Lagoon. It is considered one of the most bio-diverse estuaries in the Northern Hemisphere. With such important national treasures and delicate environments, Brevard was aware for the need to be prepared for major weather events. Unfortunately, the below ground infrastructure was not as ready. Brevard County Utilities operates and maintains over 500 miles of gravity wastewater mainline, across 291 lift stations, ranging from 6'-30' inch. Over 95% of these pipelines are 12-inch and below and consist of PVC and VCP materials. There are also 6 WWTPs in various unincorporated locations of the County, the largest which operates at 6mgd. In 2017, with storm surges and rainfall from Hurricane Irma, the WWTPs were unable to handle the increased flow, resulting in a discharge of 100mil. gallons of untreated water to the Indian River Lagoon. The water was clear, which was evidence of extreme I/I from Irma's weather. Rainfall was getting into the system through structural deficiencies and overwhelming an already fragile network — resulting in significant costs via pump station run times, treating water, and environmental consequences. These effects did not go unnoticed by Commissioners and the public. For weeks after Irma, reports of sewage and wastewater debris were noted in the Lagoon and along the Anchor Drive Canal. For the Utility, it was either discharge or have this backup into people's homes. The County was in the midst of an extensive Capital Improvement Program (CIP) for fixing these pipes and manholes but had not made enough of an impact to mitigate Irma's torrent. The program involved CIPP lining of entire areas of the system. Due to public outcry, lining became the go-to project resulting in entire basins being lined without prior investigation. It seemed like a perfect 'quick fix'. However, it was costly. Over the span of 2017-2019, not enough pipes were completed using the County's annual budget. At the rate they were going, it would take decades to line everything. The need for prioritization was apparent. In 2019, Brevard utilized a contract from nearby Palm Bay for sewer inspection services. While the concept of inspection was not new, the technology was new to Brevard. Robotic crawlers capable of inspecting 3-4x the footage of a conventional camera was exactly the solution they needed. The company, RedZone Robotics, manufacture an autonomous CCTV camera called Solo designed for 8-12' pipelines — over 95% of Brevard's collections system. It is equipped with 2 cameras, one on the front and rear, creating a 360-degree video of inside the mainline. It did not require a box truck and could be easily transported into easements, rear lots, or other harder to access areas. Traffic control was also reduced significantly. Where the value peaked for the Utilities department, was in the speed and spend. The services provided by RedZone would allow for larger portions of the system to be inspected using NASSCO's PACP standard. While the budget did not allow for the entire system to be inspected in one year, it did allow enough to create a prioritization program. The Solo units could confirm which pipes were in need of repair, and after analysis of risk and criticality scoring, rank those pipes for CIPP-lining need. The Solo units were operated on an 'Inspect-to-Clean' approach. On average, 70%-80% of a system does not need to be cleaned in order to inspect. The defects that cause blockages are also not likely to be resolved by jetting: roots and intruding taps are some of the biggest inhibitors. By placing a camera into the pipe and determining condition, the right tool can then be used, saving on cleaning costs in the process. In 2019, Brevard halted their lining efforts and converted to inspections. Starting in May, through June 2021, over 1.6mil LF of pipe was assessed using the Solo. By applying the PACP ratings, any pipes identified as having a grade level 4 or 5 structural issue were placed onto the priority list for criticality assessment. Using Esri's ArcGIS platform, the Utility could denote key environmentally sensitive areas within the County, to place pipe assets nearby higher in rank for rehabilitation and lining projects. Any grade level 4 or 5 O&M issues were then handled internally by the Operations to perform cleaning and mitigate any potential overflow. The initial results confirmed two things: 1) The system was not in bad shape. Basins that were set to be entirely lined showed that many of the pipes were still in good structural condition, free of defects. 2) By lining the most troubled spots after assessments, pump station run times were reduced by 50% - going from an average of 200gpm to 100gpm. Switching to a baseline assessment was proving to be a great strategy. Despite there still being evidence of I/I, the reduction in the power consumption and use of those lift stations was monumental. On future wet weather events, there was little worry about the ability to convey and treat that water. In October 2020, the County began incorporating manhole inspections into the program alongside the pipe. As another vital component of the collections system, the need for assessment and rehabilitation of failing access points could not be ignored. By May 2021, nearly 5000 manholes had been assessed using NASSCO's MACP. As of today, over 2mil. LF of pipe (66%) and 8,000+ manholes (60%) have been inspected. Using the 'Inspect-to-Clean' approach, approximately 275,000 LF of pipe was identified as needing to be cleaned. This amounted to only 9% of the system! As for structural issues and the lining program, approximately 134,000 LF of pipe contained a grade level 4 or 5 defect (4%) and ~250 manholes that would require rehab. While these lining programs would be expensive, these results further confirmed Brevard's approach to inspecting first. Without a baseline assessment, Brevard would have spent their resources 'fixing' problems that were not likely to exist in the system. The issues identified from Irma were not insurmountable. The key to tackling the problem was investigation: using CCTV collection and NASSCO scoring, delivered via robotic technology, to create an effective condition assessment program. The data is actionable and defensible. By tying it back to their GIS and using risk scoring, it enables the Utility to be in sync for improving the system before the next hurricane arrives.This paper was presented at the WEF Collection Systems and Stormwater Conference, April 9-12, 2024.SpeakerWhite, ChrisPresentation time09:00:0009:30:00Session time08:30:0011:45:00SessionCollection System InspectionSession number28Session locationConnecticut Convention Center, Hartford, ConnecticutTopicCoastal Systems, Collection Systems, Condition Assessment, Consent Orders, Construction, Design considerations, Flow control, Force Mains, Infiltration/Inflow, Innovative Technology, LiDAR surveying, Pipe, Pipe Failures, Real Time Decision Support System, Real-Time Control, Rehabilitation, Slip line, Utility Management, Wastewater ManagementTopicCoastal Systems, Collection Systems, Condition Assessment, Consent Orders, Construction, Design considerations, Flow control, Force Mains, Infiltration/Inflow, Innovative Technology, LiDAR surveying, Pipe, Pipe Failures, Real Time Decision Support System, Real-Time Control, Rehabilitation, Slip line, Utility Management, Wastewater ManagementAuthor(s)White, ChrisAuthor(s)C. White1, E. FontaninAuthor affiliation(s)RedZone Robotics 1SourceProceedings of the Water Environment FederationDocument typeConference PaperPublisherWater Environment FederationPrint publication date Apr 2024DOI10.2175/193864718825159352Volume / Issue Content sourceCollection Systems and Stormwater ConferenceCopyright2024Word count13