WaterWastewater Treatment and Sustainability Dr Zuzana Bohrerova Ohio

Water/Wastewater Treatment and Sustainability Dr. Zuzana Bohrerova Ohio Water Resources Center Civil, Environmental and Geodetic Engineering

Water Sustainability What is sustainability? Conference on Sustainable Development 2012 (Rio+20): Water is “at the core of sustainable development as it is closely linked to a number of key global challenges”

Water Sustainability SOURCE: UN water. org, 2013 Triple bottom line approach to sustainability: ENVIRONMENTAL ECONOMIC SOCIETAL

Water Sustainability • Are we using water in sustainable manner?

Water Use

Water Use

Water Footprint SOURCE: UN water. org, 2013 • http: //www. waterfootprint. org/? page=files/productgallery

Water Scarcity • 41% of the world’s population lives in river basins suffering from moderate to high water stress

Water Quality SOURCE: UN water. org, 2013

Achieving Sustainability Goals (UN) • TARGETS (draft, after 2015) – Universal access to safe drinking water, sanitation and hygiene – Improve by x% the sustainable use an development of water resources in all countries – All countries strengthen equitable, participatory and accountable water governance – Reduce untreated wastewater by x%, nutrient pollution by y% and increase wastewater reuse by z% – Reduce mortality by x% and economic loss by y% from natural and human-induced water-related disasters

Significance of Water Resources – U. S. perspective Drinking water in US is among the best in the world, BUT • Emerging contaminants threaten our water supplies – Microcystin, Perchlorate, Arsenic, PHACs • Development in arid, coastal regions • Many waters are not “fishable and swimmable” • Water/wastewater infrastructure security • Water x Energy Nexus issues

Current Urban Water Cycle 5% Q Waste sludge, brine (to disposal) Groundwater or surface water inputs (Q) WTP Loss to leakage (33%Q) Waste sludge, brine (to disposal) 5% Q City Distribution System Outfall 57 -66% Q WWTP • Linear centralized treatment system based on disposal

Current Urban Water Cycle • Current urban wastewater management is linear treatment system based on disposal – Abuse of water for diluting human excreta – High cost for running and operating current systems – Collection infrastructure and fast development • Need of sustainable, closed-loop urban wastewater management system based on conservation of water and nutrients

Approach to Water Infrastructure Traditional New Sustainable Rapid conveyance – underground Keep significant portion of the concrete pipes and large treatment source, use, treatment, and/or plants disposal at the local level (site) Goal – protect public health and receiving water, flood control Expand to lighter ecosystem footprint and enhanced community benefits Industrial model of specialization Integrate water, wastewater and stormwater – One water Siloed infrastructure, funding, regulations and management Multiple uses and reuses Driver – economies of scales – bigger is better True cost pricing - externalities Potable water for all uses Water quality sufficient for intended use Nelson, Sustainable Water Infrastructure

Water Energy Nexus • Water and energy systems are interdependent SOURCE: DOE, energy. gov, 2014

Electricity Use for Water/Wastewater Treatment in US • Uses 4% of nation’s electricity • Majority for moving water/wastewater (80%), rest treating • Groundwater supply as water source requires 30% more electricity (versus surface water) • Increases in energy consumption: – Age of delivery systems (friction increase, efficiency decrease) – Conservation (systems will operate on below minimum level; trend to smaller system; economies of scale) – Improve treatment requirements – Advanced wastewater treatment 3 x more electricity than trickling system

Drinking water treatment • EPRI

Wastewater treatment

Decentralized vs centralized systems Centralized Decentralized Advanced collection and treatment Treated onsite Out of sight More public participation One technology for a region Flexibility in process used and management More expensive for capital cost and operation and management Expenses transfer to individuals Control and regulation easy Hard to control and regulate Lower spatial requirements per capita Space requirements Operator expert Everyone expert

Some more sustainable WWT technologies- developing world • Lagoons/wetlands – Climate – Land – Reuse potential? • Anaerobic digesters (USAB) – Small and large scale – Biogas production and stable humus – Operation • SAT (Soil Aquifer Treatment) technologies – Partially treated effluent used for recharge (Gaza) – Breaks pipe-to-pipe connection – Could lower WQ of groundwater

Evaluation Sustainability of WWTP Muga and Mihelcic, 2008, Journal of Env. Management, 88: 437 -447

Wastewater operators

Land Requirements

Utility Services Leading Sustainability From US EPA: • Alternative fuels • Automation • Resource recovery • Resiliency • Customer engagement – conservation • Investment in capital facility maintenance

Water Reuse • Not the only solution • Needs to be combined with: – – – water conservation alternative water supply green infrastructure development in treatment technologies environmental restoration

Water Quality Change • Electricity consumption decreases sustainability of water reuse (LCA)

Reclaimed water use

Water Reuse for Irrigation • Most reclaimed water contain TDS – salts • Irrigation needs to be evaluated for long term sustainability of soil resources • Salt accumulation in soils – change in root osmosis and ability to grow (uptake nutrients and water) • Israel about 70% reuse water used for irrigation – salinity problem. – Strict source control (what is discharged into wastewater) – Changes in water softening agents and detergents • Emerging contaminants

Domestic Water Reuse – dual reticulation Water corporation, Australia, published online

Water reuse and treatment process

Reverse Osmosis Advantages Disadvantages Modular assembly system Water needs extensive pretreatment Installation cost low Interruption during stormy weather (too many organics in feed water) High space/production capacity ratio Need for extensive spare parts inventory Low maintenance Brine disposal Removes TDS Energy costs Negligible environmental impact Needs reliable energy source Minimal use of chemicals Membrane fouling Future development: better membranes, lower energy requirements

San Diego

San Diego toilet to tap • Facility available and treating wastewater • Regulations not in place • Public oppose direct potable use, but willing to use as indirect potable use http: //www. sandiego. gov/water/purewater/demo/index. shtml

• Toilet to tap feasible – biggest hurdle is public perception Scientific American, CREDIT: Sam Kaplan; STYLING BY LINDA KEIL Halley Resources

Blue Print Columbus • Sanitary sewer overflows has to be eliminated • Solution – Green infrastructure – OARS deep sewer tunnel http: //www. youtube. com/watch? v=do 6 j. Fv_Hdb. E&feature=youtu. be

References • Kennedy, L. and Tsuchihashi, R. (2005), “Is Water Reuse Sustainable? Factors Affecting its Sustainability. The Arabian Journal for Science and Engineering, 30(2 C), 3 -15 • Jhansi, S. C. and Mishra, S. K. (2013), “Wastewater Treatment and Reuse: Sustainable Options”, Consilience: The Journal of Sustainable Development, 10(1), 1 -15