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Water Quality – challenges to human health and ecosystems. Good news – U.S., other developed countries have reduced “point source” discharges (over 90%) since 1970 – through permits, effluent fees, pollution taxes. Bad news –
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Water Quality – challenges to human health and ecosystems • Good news – • U.S., other developed countries have reduced “point source” discharges (over 90%) since 1970 – through permits, effluent fees, pollution taxes. • Bad news – • Less-developed countries not making progress in reducing waste discharges: weak regulation of industry, untreated sewage, lack of funding for treatment. • Developed and developing nations struggle with “non-point” pollution –runoff from paved surfaces & farms. • Nitrate pollution of groundwater growing (1980s – 2004) due to agricultural use of pesticides and fertilizer.
Water and public health – issues • About 2.6 billion people lack a simple ‘improved’ latrine and 1.1 billion have no access to improved drinking water sources. As a result: • 1.6 million people die annually from diarrheal diseases (e.g., cholera) due to lack of access to safe drinking water/basic sanitation (90% are children < 5). • 160 million people are infected with schistosomiasis causing tens of thousands of deaths yearly. • 500 million people are at risk of trachoma from which 146 million are threatened by blindness and 6 million are visually impaired;. • Intestinal diseases plague the developing world due to inadequate drinking water, sanitation and hygiene; 133 million suffer from high intensity intestinal infections; approximately 1.5 million cases of clinical hepatitis/year. • Source: Water for People, Water for Life, UNESCO, 2003
Taihu Lake, Jiangsu province, China Blue green algae blooms caused by nitrogen/phosphorous laden runoff into calm, warm lake – near Yixing, in E. China
What can developing countries do? • Latin American Clean Water Initiative – a collaboration between UN Partnerships for Sustainable Development and Agenda 21. • Goal: respond to lack of clean, safe drinking water in Latin America: • 60 million people in Latin America and Caribbean live without access to potable water – most are low income families. • 134 million people lack adequate sanitation systems. • Contaminated drinking water has devastating effects on most vulnerable communities; water-related illnesses are second leading cause of death. • Methods: • Partners in 15 countries install potable water and sanitation systems . • Provide education and training on proper management of water systems , water purification, health and hygiene.
Objectives: • Construct complete potable water systems including taps, outdoor washbasins, water tanks, and latrines. • Improve irrigation systems. • Improve degraded water systems. • Involve beneficiary families in construction and/or repairs of water systems. • Train communities to manage and administer potable water and sanitations systems in order to ensure long-term sustainability. • Offer training in health issues related to water-borne illnesses, water management, and environmental conservation.
Innovations to address non-point pollution 1. Environmental restoration 2. Pollutant trading 3. Incentive-based practices 4. Green-building practices
Environmental restoration • Goal – reduce erosion, avert runoff/sedimentation of streams – to prevent contamination & fish kills. • Method – Restore stream-banks, re-introduce native vegetation, re-plant river banks: • Build parks, recreation areas. • Involve public in projects & in monitoring water quality. • Many “River keeper” groups being formed worldwide.
Tuolumne River restoration – near Stanislaus, CA: native riparian plantings to reduce erosion/sediment & help restore Chinook salmon (Restoringrivers.org)
Restoration through dam removal Before removal After removal Sheboygan River, Wisconsin
Pollutant trading • Goal – negotiate pollutant “offsets” to reduce pollution. • Example – North Carolina’s Tar-Pamlico River basin: • Problem: Low dissolved O2, fish kills, vegetation loss. • Causes: nitrogen/phosphorus runoff from farms/point discharges from cities. • 1992: North Carolina developed a “nutrient trading framework.“ • Farmers paid by cities to implement “nutrient reduction plans” to reduce nitrogen/phosphorous emissions. • Cities, in turn, got permission from EPA not to upgrade municipal water treatment facilities – a cost saving! • Has achieved NC’s goals – reduced non-point pollution, lower economic burden to municipal dischargers. Can it be sustained?
Incentive-based practices • New York – nation’s largest city without a drinking water treatment plant: • Water comes from Catskills/Croton watersheds. • Hardwood & evergreen forests filter water, retard erosion. • Bad news – since 1970s, water quality has worsened from sewage/ agricultural runoff; land cleared for residential development. • Options? • Build artificial filtration plant: estimated cost = $6-8 billion, annual operating costs = $300 million. • Restore Catskill/Croton watersheds – purchase land, compensate property owners for growth restrictions, subsidize septic system improvements: cost = $200 million – paid through bonds. • It works, BUT due to growth, may eventually have to build filtration plant.
Green building and water management – the “whole building approach”
New water quality threats • Pharmaceutical and Personal Care Products (PPCPs) in water supplies – • Prescription & over-the-counter therapeutic drugs • Veterinary drugs • Fragrances, cosmetics, sun-screen products • Diagnostic agents • Nutraceuticals (e.g., vitamins) • Caffeine • Major health/environmental concerns? • Endocrine disruptors – in humans and aquatic species • Human fetal exposures – low-level but chronic toxicity • Long-term health effects not well-known – accumulate over time; may be passed down through generations; low doses can affect children/infants.
Monitoring for PPCPs • National sampling has found 95 common compounds; 1/3 of which are unregulated antibiotic/anti-bacterial compounds that defy conventional treatment – most are NOT removable by conventional sewage treatment. • In U.S., several agencies (NIEH, USGS, EPA) studying problem: • Extensive long-term monitoring of PPCP accumulation in water supplies • New, expensive technology to remove PPCPs (granulated carbon, UV light) • Challenge – finding water treatment technologies that remove pathogens while minimizing creation of hazardous disinfection by-products.
Public policies • From U.S. EPA (2008) – what YOU can do: • Dispose in trash • Use community “take back” programs to dispose of PPCP products • Only flush down toilets if labels say to do so • What public officials can do: • Greater public education to avoid careless exposure – most PPCPs enter water supplies through disposal in toilets, sinks. • Detection measures to deter deliberate PPCP contamination (a homeland security issue) need to be developed.