1. Effects of Disasters on Wastewater Treatment and Collection Systems
Bradley Crain
May 7, 2019
2019 Mississippi Partners in Preparedness Summit

2. The best time to act is in the first phase of the disaster cycle, when preventative and mitigation measures can strengthen a system by reducing its vulnerability to hazards
Pan American Health Organization. (1998). National Disaster Mitigation in Drinking Water and Sewage Systems. Washington, D.C. PAHO

3. The Big Picture Effects
Human health
Direct contact with contamination
Environmental impact
Inability to maintain its designated use
Damage infrastructure
Broken pipes, Damaged electrical components, Structural damage
Removes us from a situation of normalcy
Basic services

4. Sewer System Vulnerabilities
A sewer system meeting standards is the first step in mitigating disaster effects
ASCE 2017 Infrastructure Report Card
Over $2 billion in wastewater needs over the next 20 years
Aging sewer collection systems
Inflow and Infiltration (I/I)
Sanitary Sewer Overflows (SSOs)
Operation and maintenance of treatment facilities
System integrity
Wastewater Operators

5. Planning Determine areas of vulnerability in the system
Develop a emergency response and mitigation plan
Evaluate the effectiveness of the plan
Inter-Institutional coordination for disaster response
It is important to have detailed knowledge of the human resources, material, and equipment available at the local level.

6. Vulnerability Analysis
Many of the problems presented by natural hazards occur because these phenomena are not considered during the conception, design, construction, and operation of the system.
Components
Identification and quantification of hazards that can affect the system
Estimation of the susceptibility to damage of components that are considered essential
Definition of measures to be included in the mitigation plan
Identification of measures and procedures for developing an emergency plan

7. Mitigation Plan
Comprises of improvement and structural retrofitting measures directed toward increasing reliability
Components
Prioritize activities
Responsible for execution
Timeframe of completion
Estimated Cost

8. Emergency Plan Components
Procedures
Instructions
Necessary information for preparing and mobilizing
Plan should be designed to respond to emergencies and disasters with the resources that are currently available, and updated accordingly.
Success will depend on how simple and practical it is to carry out, as well as on the knowledge of the persons involved.

9. Natural Hazards Impacts
Types of disasters affecting sewer systems
Floods
Tornadoes
Winter storm
Hurricanes
Earthquakes

10. Surface Structures Buildings What operations are performed?
Power outage
Access
Communication

12. Surface Structures Tanks Cracks Collapse Debris Broken connections
Power outage
Controls
Chlorine
Exacerbated with poor maintenance

14. Surface Structures Reservoirs and lagoons Sewer pipes Pump stations
Overtopping
Collapse
Leaks
Exacerbated with poor maintenance
Sewer pipes
Rupture of aerial crossings
Pump stations
Controls/ power outage
Damage to surface pumps
Outlet structure

18. Underground Structure
For the most part, damage will not be visible, making actual damage assessment much slower and more labor intensive.
Sewage Pipes
Underground breaks
Contamination
Submerged
Siltation/ Debris
Uncovered manholes
Exacerbated with poor maintenance

21. Underground Structure
Pump Stations
Flooded
Siltation/ Debris

23. Human Health Concerns
Avoid both cross-contamination and direct contact
Waterborne disease outbreak examples
Giardia
Chemical
Shigella
Rotavirus
Hepatitis

24. Wastewater Disaster Prep
Means for Independent Communication
Disinfection/Chemical Inventory
Alternative chemical feed at treatment plant
Lime for sewer spills
Copy of Sewer Collection/ Treatment Plans
GIS Mapping

26. Wastewater Disaster Prep
Detail Pump Station Information
Pump size
Electrical Requirements
Quick-Connect
Power and Bypass Piping
Mutual Aid Agreements
Drain Holding Ponds
Have Response Equipment Ready to Go

28. Wastewater Disaster Prep
Prepare for power outages
Auxiliary/ standby equipment
Battery charges
Fuel supply (10 to 14 days)

31. After the Disaster Survey and assess damage
Needed Repair
Time to Complete
Prioritize
Proceed on Repairs
Determine locations of power loss
Stop electrical current to damaged equipment
Determine extent of wastewater or biosolids flooding to determine exposure risk.

32. After the Disaster Coordinate with water utility Keep public informed
If possible, list stations and treatment facility should be operational prior to restoring water service.
Keep public informed
System Damage
Public health or environmental concerns
Supply of lime for disinfection of spills of raw, partially treated, and fully treated wastewater.

33. After the Disaster Reporting Sewer System Damage
Major Damage to MEMA ESF-3 and MDEQ
Minor damage report as soon as possible
MDEQ staff is available to offer assistance pre/post-disaster.