1.3 Invest in infrastructure to minimize wastewater spills, emergency releases, and overflows

Key Message: Spills, emergency discharges, and overflows of treated and untreated sewage cause significant harm to environmental and human health. A proactive and comprehensive approach to preventing unplanned discharges should include inspection, maintenance, replacement, and upgrades of failing sanitary sewer infrastructure.

Importance

Wastewater spills, emergency releases, and overflows are episodic sources of localized pollution that threaten environmental, economic, and public health. Bacteria and viruses from untreated wastewater directly threaten human health and high priority is given to cleaning up and disinfecting raw sewage discharges. Nutrient pollution from untreated and treated wastewater discharges has received less attention. Nutrients in unplanned discharges can enter waterways, degrade water quality, and fuel harmful algal blooms that can threaten recreational and economic activities and public health.

Aging and failing infrastructure, clogs, lack of reliable disposal capacity, population growth, and climate-related stressors will further strain centralized wastewater collection, treatment, and disposal systems already prone to spills, emergency releases, and overflows.

Overview

Central wastewater collection systems in Sarasota County convey raw sewage with gravity and vacuum systems to lift stations, which then pump the wastewater to Wastewater Treatment Facilities (WWTFs) via pressurized force main pipes. Depending on treatment level, wastewater effluent can be discharged into surface waters, injected into underground wells and aquifers, sprayed on infiltration basins, or reclaimed for beneficial uses like irrigation (see Chapter 1.1). Collection, treatment, and disposal infrastructure can fail for many reasons:

  • Aging infrastructure can deteriorate over time. In some locations in Sarasota County, wastewater infrastructure is near or past its functional lifespan.
  • WWTFs in Sarasota County have enough capacity for accepting raw sewage, but disposing of the volume of treated wastewater is a growing challenge, especially in wet season. The County’s reclaimed water system utilizes ground storage tanks and ponds for seasonal storage and a deep injection well for wet weather.
  • Sanitary sewers in Sarasota County were not designed to accept stormwater or groundwater, which can cause overflows. Infiltration of stormwater or groundwater occurs through broken, permeable, or defective pipes, most commonly during heavy rainstorms. Inflow occurs through unauthorized connections.
  • Storms cause electrical failures at lift stations, resulting in overflows. Lift stations constructed prior to 2003 were not required to have an emergency back-up generator (BGATF 2019).
  • Pipes are blocked by tree roots as well as fats, oils, and grease (FOG), baby wipes, and sanitary products improperly disposed in drains and toilets.

Climate-related stressors, including sea level rise, more frequent and intense rainfall events, and storm surge will compound existing vulnerabilities of wastewater infrastructure in Sarasota County and its municipalities (SBEP and Shafer 2017, City of Sarasota 2017, BGATF 2019).

Anticipated increases in storm intensity may increase inflow and infiltration and overwhelm sewer system capacity. Rising sea levels can elevate groundwater and increase infiltration, corrode infrastructure, and alter the effectiveness of wastewater treatment.

During heavy rainstorms, sewer systems with cracked pipes can flood with groundwater causing manholes to overflow. Source: Iain Cuthbertson

Over the past decade, nearly 23,000 wastewater spills were reported in Florida. About 5.77 million gallons of untreated sewage and 1.72 million gallons of partially treated sewage was spilled in Sarasota County from 2009 to 2018, altogether more volume than 11 Olympic-size pools (Salman et al., 2019). In addition, 57.5 million gallons of reclaimed water (treated for pathogens but not nutrients) was spilled in the last 10 years in Sarasota County. Causes of these incidents range from line breaks to heavy rainfall (Figure 1.3.1).

Figure 1.3.1. Number of incidents, causes, and volumes of wastewater spills, overflows, and releases in Florida from 2009–2019. “Other” includes repairs, accidents, contractor negligence, and causes unknown. Source: FDEP cited in Salman et al., 2019

Sarasota County Government’s wastewater collection infrastructure includes approximately 700 lift stations, 760 miles of gravity sewer lines, and 17,800 manholes. The Florida Department of Environmental Protection (FDEP) requires utilities to report within 24-hours any unauthorized releases of wastewater to surface or groundwater and any wastewater spills greater than 1,000 gallons (Chapter 62-620, F.A.C.). These reports have been available to the public on the FDEP website since July 2017 (see Chapter 1.4). Based upon these data, there were 104 reported incidents in Sarasota County in 2018 (FDEP, 2019a) (Figure 1.3.2).

Figure 1.3.2. Reported wastewater spills, overflows, and releases associated with major wastewater treatment facilities in Sarasota County in 2018. City of North Port had no spills reported in 2018. Source: FDEP

Sarasota County’s Water Pollution Control Code provides for enforcement and fines of up to $10,000 for unauthorized discharges to surface water, groundwater, the ground surface, or stormwater. Public Utilities staff respond immediately to all reported spills for cleanup, assessment, and monitoring. Fines levied on privately owned facilities and private contractors are deposited to the Pollution Recovery Trust Fund held by Sarasota County Clerk and used for spill cleanup, monitoring, and environmental restoration. Recent Trust Fund projects have included spoil island restoration. A maximum of 10% of funds can be allocated to administration and enforcement activities.

Sarasota County Government utilities staff is creating a Capacity, Management, Operation, and Maintenance (CMOM) program to improve wastewater system operations and minimize sanitary sewer overflows. CMOM programs shift maintenance actions from reactive to proactive, creating operational efficiencies, lowering risk, and saving money by reducing emergency response costs. They also improve communications within the organization, and with regulators, other municipal partners, stakeholders and the public. The Sarasota County Board of County Commissioners recently approved a five-year, nearly $4 million contract with an engineering firm to assist in plan development.

One priority challenge is the lack of adequate disposal capacity at the Bee Ridge WWTF throughout the year (see Chapter 1.1). This need for additional storage capacity was identified in Sarasota County’s Reclaimed Water Master Plan (2013). Sarasota County Government is addressing this issue by upgrading the facility to AWT, increasing treatment capacity from 12-million to 18 million gallons per day, and drilling two aquifer recharge wells to inject reclaimed water 1,700 feet into the ground during the rainy season when there is reduced demand for irrigation. The project’s estimated cost is $157 million with an anticipated completion date of late 2025. 

The Clean Waterways Act (2020) creates a wastewater grants program within FDEP that provides a 50% match to local funds for constructing, upgrading, or expanding facilities to provide advanced wastewater treatment. The measure also gives priority in the state revolving loan fund for wastewater projects that prevent leakage, overflows, infiltration, and inflow. It also substantially increases FDEPs regulatory penalties for failing to prevent spills. In addition, the Environmental Accountability Act (2020) increases penalties by 50% for violations of a variety environmental laws resulting in harm to air, water, or land.

Approach

An integrated suite of planning and policy initiatives; improvements to infrastructure management, maintenance, and operation; investment in upgraded infrastructure, and education and outreach is recommended:

  • Encourage proactive inspection, maintenance, replacement, and upgrades of failing sanitary sewer infrastructure. Priorities could include emergency electrical backup systems for priority lift stations lacking them; upgrading priority wastewater plants to AWT to expand disposal capacity (see Chapter 1.1); and identifying and fixing broken or leaking pipes.
  • Develop legislation and funding assistance to support proactive inspection, maintenance, replacement, and upgrades of inadequate sanitary sewer infrastructure (see Chapter 9.3).
  • Support Sarasota County’s Wastewater Master Plan and CMOM program.

Increase public outreach and education about the need for proactive inspection, maintenance, replacement, and upgrades of inadequate sanitary sewer components to build support for infrastructure investment (see Chapter 1.5).

Resources

FDEP Public Notice of Pollution database
https://floridadep.gov/pollutionnotice

Status

Capacity, Management, Operation, and Maintenance (CMOM) program development in progress.

Upgrade of Bee Ridge WWTF to AWT in progress.

Performance Measure

Reduced spills, releases, and overflows as documented by FDEP incident reports

Experts or Leads

State legislators, Sarasota County Government and Municipalities utilities staff

Cost Estimate

$1,000,000+

Related Activities

Chapter 1.1, Chapter 1.4, Chapter 1.5, Chapter 9.3

 

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Other Wastewater Activities

1.4 Improve FDEP public reporting of wastewater discharges

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