These adaptation strategies offer possible ways to address the changes in wastewater treatment due to climate change.
Adaptation strategies for wastewater treatment
- Evapotranspiration cover modification
- Replacing existing vegetation with a plant mix more tolerant of long-term changes in precipitation or temperature, and/or soil addition will increase water storage capacity.
- Plantings
- Installing drought-resistant grasses, shrubs, trees, and other deep-rooted plants will provide shading, prevent erosion, provide windbreaks and reduce fire risk.
- Construction at grade
- Designing a new containment system to be built at the surface, instead of belowground, will minimize potential contact between groundwater and targeted waste (or an engineered liner) and prevent contamination.
- Deposition controls
- Engineered structures, such as dams, will control the flow of flood-related deposition in settings where increased underwater deposition enhances remedy performance.
- Flood controls
- Building one or more structures to retain or divert floodwater, such as vegetated berms, drainage swales, levees, dams or retention ponds will reduce the risk of damage from flooding.
- Power from off-grid sources
- Constructing a permanent system or using portable equipment provides power generated from on-site renewable resources, as a primary or redundant power supply, that can operate independent of the utility grid when needed so the system can keep running even if power is lost.
- Retaining wall
- Building a structure (commonly of concrete, steel sheet piles or timber) to support earth masses having a vertical or near-vertical slope will hold back loose soil, rocks or debris and prevent damage to the system.
- Renewable energy system safeguards
- Building extended concrete footing for ground-mounted photovoltaic systems, adding additional bracing for roof-top photovoltaic or solar thermal systems, and adding additional masts for small wind turbines or windmills will help protect the systems from damage. For utility-scale systems, safeguards to address climate change vulnerabilities may be addressed in the site-specific renewable energy feasibility study.
- Run-on controls
- Building one or more earthen structures (such as vegetated berms, vegetated swales, or stormwater ponds) or installing fabricated drainage structures (such as culverts or French drains) at vulnerable locations will prevent stormwater accumulating at higher elevations from reaching a wastewater treatment system and causing damage.
- Tie down systems
- Installing permanent mounts that allow rapid deployment of a cable system extending from the top of a unit to ground surface will hold structures in place in extreme weather events.
- Well-head housing
- Building insulated cover systems made of high-density polyethylene or concrete will protect control devices and sensitive equipment situated aboveground for long periods. and sensitive equipment situated aboveground for long periods.
- Alarm networks
- Integrating a series of sensors linked to electronic control devices that trigger a shutdown of the system, or linked to audible/visual alarms that alert workers of the need to manually shut down the system, when specified operating or ambient parameters are exceeded will help prevent contaminants from leaving the system.
- Hazard alerts
- Using electronic systems that actively inform subscribers of extreme weather events or provide internet postings on local/regional weather and related conditions will inform managers when risk is high and they need to implement protective measures.
- Modeling expression for MNA
- Incorporating additional subsurface parameters and sampling devices in monitoring plans will gauge the potential for re-suspension of contaminated sediment under more extreme weather/climate scenarios.
- Remote access
- Integrating electronic devices that enable workers to suspend pumping or selected activities during extreme weather events, periods of impeded access or unexpected hydrologic conditions can prevent contaminants from being released from the system.
- Weather alerts
- Electronic systems actively inform subscribers of extreme weather events or provide internet postings on local/regional weather and related conditions to help prepare the system in the event of extreme weather.
- Conduct an energy efficiency audit and install energy efficiency improvements
- Energy efficiency improvements in wastewater treatment facilities save energy, generate cost savings, reduce emissions, and improve overall energy security in the community.
- Relocation
- Moving selected system components to positions more distant or protected from potential hazards will help decrease the risk of damage to the system. For flooding threats, this may involve moving to elevations higher than specified in the community's flood insurance study.
- Utility line burial
- Relocating electricity and communication lines from overhead to underground positions will prevent power outages during and after extreme weather events.
- Armor
- Placing fixed structures on or along the shoreline of flowing inland water will help mitigate the effects of erosion and protect site infrastructure. Soft armor may comprise of synthetic fabrics and/or deep-rooted vegetation while hard armor may consist of riprap, gabions and segmental retaining walls.
- Coastal hardening
- Installing structures will stabilize a shoreline and shield it from erosion, through "soft" techniques (such as replenishing sand and/or vegetation) or "hard" techniques (such as building a seawall or installing riprap).
- Armor enhancement for in situ cap
- Adding additional or deeper layers of stone and/or gravel above a sand base layer will help withstand scouring forces of ice jams.
- Amendment settling enhancement
- In situ placement of amendments through techniques such as broadcasting the material in a pelletized form or using a thicker layer of coversand will accelerate material settling.
- Concrete pad fortification
- Repairing concrete cracks, replacing pads of insufficient size or with insufficient anchorage, or integrating retaining walls along the pad perimeter will prevent future failures.
- Containment fortification
- Placing riprap adjacent to a subsurface containment barrier located along moving surface water will help minimize bank scouring that could negatively affect barrier integrity. For soil/waste capping systems vulnerable to storm surge, installing a protective vertical wall or armored base to absorb the energy of the surge to prevent cap erosion or destruction.
- Entombment
- Enclosing vulnerable equipment or control devices in a concrete structure will prevent exposure to outside factors that could damage it.
- Ground anchorage
- Installing one or more steel bars in cement-grouted boreholes (and in some cases accompanied by cables) will secure an apparatus on a ground surface or reinforce a retaining wall against an earthen slope.
- Tie down systems
- Installing permanent mounts that allow rapid deployment of a cable system extending from the top of a unit to ground surface will hold structures in place in extreme weather events.
Source Documents
These strategies are adapted from The Climate Change Adaptation Technical Fact Sheet Series. For more information please view these strategies in the context provided by the primary source document.
Disclaimer
The adaptation strategies provided are intended to inform and assist communities in identifying potential alternatives. They are illustrative and are presented to help communities consider possible ways to address current and future climate threats to contaminated site management. Read the full disclaimer.
