Nutrients and Water Quality A Region 8 Collaborative Workshop February 15-17, 2011 By Bob Clement, Environmental Engineer M.S.

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1 Nutrients and Water Quality A Region 8 Collaborative Workshop February 15-17, 2011 By Bob Clement, Environmental Engineer M.S./Microbiologist

2 Goals: Nutrients have a huge impact on drinking water treatment Nutrients have a huge impact on public health Nutrients create such complexity in so many different fields of science the hope of its solution lies in our collaborative efforts

3 The body of literature on nutrient loading and drinking water treatment alludes to: The elimination of nutrient sources as the most effective way to eliminate impacts, but the predominant source is non-point. Some say, it s impossible to eliminate non-point sources We will hear presentations during this workshop that will challenge that position Others say, given the difficulties of reducing both non-point and point sources of nutrients, we should instead focus on water treatment But is this possible?

4 The effect of nutrients on ground water and surface water sources is as divergent as two different worlds. The only common thread is, that it may cost millions to remedy. For ground water, nitrogen is present as nitrate. Treatment is reverse osmosis, ion exchange, or biodenitrification. Only the last eliminates nitrate by converting it back to N 2 and CO 2. But for surface water, the nitrogen is taken up by biota and creates a whole different world of technically challenging and complicated problems. This presentation will focus on surface water treatment.

5 A facility like this will supply you with the 3-1/3 55-gallon drums you need each year of an essential nutrient for your body Drinking Water River supply Nutrients can cause a cascade of problems that can cost tens of thousands to millions to remedy This is the tip of a needle. ~2,000 Cryptosporidium cysts can fit on the tip of needle. Only a few are needed to cause severe illness. We all have a stake in safeguarding our drinking water The only safe water is treated water. Treatment reduces risk to pathogens and over 90 contaminants while trying to avoid creating new contaminants with treatment operations & chemicals. An epic balancing act!

6 Given adequate light to support photosynthesis, algae and subsequent biomass concentrations remain low. If sufficient light, carbon dioxide, and water alone do not cause algae blooms what does? Excess nitrogen (N) and phosphorous (P), more so than any of the other required macronutrients, leads to algae blooms. Increases in biomass is roughly proportional to increases in N & P

7 Autotrophs are the beginnings of the food chain Autotrophs create carbohydrates, fats, and proteins from inorganic chemicals and sunlight For water, the autotrophs are algae 300,000 species of algae, including blue-green algae which is actually a bacteria Hamilton Reservoir, Fort Collins, Colorado Excess N & P vastly increases algae levels Heterotrophs all animals, fungi, bacteria, and protozoa increase due to the abundance of algae Carnivorous organisms increase due to the abundance of heterotrophs

8 No regulations to monitor for N & P or algae at the source for a Water Treatment Plant (WTP) Subsequently, few WTPs proactively monitor for algae blooms. Thunderbird Lake, Boulder Colorado The bloom causes a severe treatment challenge that WTPs can rarely get ahead of, leading to a cascade of technical problems: This is exacerbated by blooms being episodic events.

9 With 300,000 species of algae there are many different ways algae can negatively impact water treatment Non-regulatory impacts: -Clogging of intake structures -Filter-clogging algae -Taste and odors -Chlorine-resistant algae (mistaken for Cryptosporidium) -Eutrophication in presedimentation ponds -Daily fluctuations in ph (as much as 2-3 ph units) Regulatory impacts: Pelican Lake, Colorado -Disinfection byproducts: 4 trihalomethanes (TTHMs) and 5 haloacetic acids (HAA5s) -Switch from chlorine to chloramines Unknown impacts: Cyanobacteria toxins Irrespective of the impact, the WTP is forced to remedy the problems.

10 Increasing Nutrient Loading of N&P -- Non-Regulatory Impacts to a WTP: Algae & Moss Can Clog the Intakes of WTPs The first sign of an intake clogging is that the flow of water into the treatment plant decreases During blooms, cleaning may be needed every 2 hours Raw water pumps may be damaged Filters may go dry, and the effectiveness of filtration may be compromised Production of finished water is reduced WTP staff must clear the intake before the filters run dry Cleaning intake screens may be difficult and dangerous due to the intake being submerged or in the middle of the river. Mandatory water restrictions Significance of clogging: Capital improvements (e.g., specially designed intakes with finer screens with mechanical cleaning or compressed air, river bank filtration )

11 Increasing Nutrient Loading of N&P -- Non-Regulatory Impacts to a WTP: Algae Can Clog the Filters of WTPs The first sign of algae causing problems at a WTP is the filamentous algae begin to clog the filters. Shorter filter runs from 24 to only 2 hrs A higher % of finished water used to backwash the filters - 5% up to 20% or more Filtration effectiveness decreases; instead of filtration occurring in all 30 inches of media, it occurs in only the top few of inches. Less water to customers at times of high demand Mandatory water restrictions Turbidity in finished water increases and may cause turbidity violations Higher turbidity potentially increases the levels of endemic disease (low level disease) The WTP has no choice but to add chemicals directly to the algae bloom A whole new set of problems Significance of filter clogging: Capital improvements (e.g., river bank filtration, advanced sedimentation, membrane filtration )

12 Increasing Nutrient Loading of N & P -- Non-regulatory impacts: Algae Causes Taste and Odors (T&O) Copper sulfate is applied, disrupts photosynthesis, and causes cell death. Some of these molecules are powerful T&O compounds The algae cell lyses, its molecular contents go into the water column Grasmere Lake, Colorado Geosmin Geosmin and MIB are the most common cause of T&O. They cause earthy, musty, fishy, grassy T&O at levels as low as 5 parts per trillion. But with >300,000 types of algae, the potential to produce disagreeable T&O not associated with Geosmin and MIB is huge. But the use of copper sulfate leads to other problems Significance of T & O: Loss of public confidence. Capital improvements (e.g., powdered activated carbon, granular activated carbon...)

13 Increasing Nutrient Loading of N & P -- Non-regulatory impacts: Copper Sulfate Selects for Algae Resistant to Copper and Chlorine. At a WTP in Colorado, copper sulfate selected for Haematococcus, an algae with thick cell walls -- it resisted copper sulfate & chlorine. It passed through the filters and tinged the city s drinking water green prompting customer complaints. An expensive, proprietary algaecide called Cutrine Plus had to be used. Nearly 100K was spent on an engineering study to solve this problem. At a WTP in WY, a chlorine-resistant algae ~ the same size as Cryptosporidium led to a false declaration of a waterborne disease outbreak during Mother s Day. It cost the city tens of thousands.

14 Increasing Nutrient Loading of N & P Non-regulatory Impacts: Algae Increases the ph on a Daily Basis Algae growth increases the ph by 2 to 3 units by evening. This diurnal ph swing causes operational havoc with WTPs Duck Lake, Denver, Colorado Potential increases of endemic disease The aluminum sulfate coagulant (most common) which removes turbidity does not work at these higher phs During the evening, the turbidity levels increase The filtration effectiveness decreases Also, diurnal swings in ph can cause daily swings in lead and copper releases from home plumbing. New studies show there is no safe lower limit for lead because of its impacts on the IQ in children. This is not addressed in the Lead and Copper Rule. Most WTPs don t monitor for ph every 2 hours; there are no regulations that require it. The effects of ph swings are unknown to most WTPs, but manifests itself as an unexplained, episodic loss of control of the water plant Significance of diurnal ph swings: Chemical addition of a acid to counter the daily ph swings. Operationally this is labor intensive and difficult to accomplish.

15 Increasing Nutrient Loading of N & P -- Non-regulatory Impacts: Algaecides Speed up the Eutrophication of Presedimentation Ponds Algae blooms cut off sunlight, limiting photosynthesis of sub-surface plants which depletes the O2 levels When the algae die, they settle to the bottom where bacteria (decomposers) propagate, further depleting the O2 levels Most presed ponds are large and were not designed to be cleaned. A light organic floc accumulates. Wind events stir it up, redistributing nutrients for more blooms and clogs the filters. Death of an ecosystem: The O2 becomes depleted, larger aquatic organisms die (fish), their decomposition further depletes O2. All the while N & P are being returned to the water column resupplying nutrients from within the pond. Significance of eutrophication in presed ponds: Capital improvements (e.g., ponds need to be dredged, or abandoned, new smaller ones built with sediment removal).

16 Increasing Nutrient Loading of N & P Regulatory Impacts: Increases in Algae and Biomass Lead to Increases in TTHMs & HAA5s and Other Disinfection Byproducts (DBPs) Increases of N & P Increases of algae & biomass (natural organic matter) Creates more potent carcinogens and a new set of DBPs that we know even less about In the world of disinfection byproducts (DBPs), this biomass is referred to as natural organic matter (NOM) and is the precursors to DBPs When chlorine is added, more than 600 DBPs can be formed, most of which we don t even know the structure of, let alone their health effects. The synergistic health effects are beyond our known science. We regulate 9 organic DBPs: 4 trihalomethanes (TTHMs) and 5 haloacetic acids (HAA5s). WTPs switch to chloramines - the least TTHM & HAA5 violations & enforcement costly treatment option Significance of increases of DBPs: Major capital improvements (e.g., riverbank filtration, enhanced coagulation, enhanced sedimentation, ozone and biologically active filtration granular activated carbon, elimination of prechlorination and building storage after filtration, microfiltration/nanofiltration, nanofiltration, ultraviolet irradiation, modifications storage tanks )

17 2010 was an extremely wet year for the Milk River watershed after years of drought. The impacts of the rain, which washed nutrients into the river, had a Alberta tremendous impact on WTPs in Montana. Saskatchewan Total Organic Carbon (TOC) September in 2009 = 3.2 mg/l (TTHMs = 25 ppb, HAA5s= 20 ppb) in 2010 = 6.0 mg/l (TTHMs = 50 ppb, HAA5s = 69 ppb) The Maximum Contaminant levels (MCL) for TTHMs = 80 ppb, HAA5s = 60 ppb. Both cities exceeded the MCL in 2010 due to increases in TOC. Chinook Montana Harlem Total Organic Carbon (TOC) September in 2009 = 4.0 mg/l (TTHMs = 87ppb, HAA5s= 52 ppb) in 2010 = 7.4 mg/l (TTHMs =181 ppb, HAA5s = 153 ppb)

18 Increasing Nutrient Loading of N & P -- Regulatory Impacts: Increases in Disinfection Byproducts (DBPs) and the Switch to Chloramine Disinfection. WTPs switch to chloramines which forms less of the regulated DBPs, but This switch creates nitrification problems. Nitrifying bacteria convert ammonia to nitrate in the distribution system. There are no regulations to protect against nitrate being formed there. To combat nitrification, WTPs switch to high levels of chlorine for a month to purposefully remove biofilm called chlorine burns. This procedure releases accumulated inorganics, radionuclides, and causes very high levels of regulated DBPs. This water is not flushed and customers ingest this water. There are no regulations to protect against chlorine burns. Chloramines have the potential to create one of the most potent DBPs know to humans - N-nitrosodimethylamine (NDMA) which is toxic in the parts per trillion level and is not yet regulated. In addition, chloramines create a new set of other unknown DBPs that we know even less about. Significance of switching to chloramines: Capital improvements (e.g., new chemical feed system, more difficult operations, unknown health concerns )

19 Increasing Nutrient Loading of N & P -- Unknown Impacts: What is the occurrence of Cyanobacteria (blue-green algae) Toxins? Perry, Utah Cyanobacteria (blue-green algae) is the major species in blooms (60 to 90% or more) But only 59% of blooms from around the world contain cyanotoxins. If the majority of algae in blooms are cyanobacteria, then why don t all blooms contain cyanotoxins? It is unknown what combination of environmental factors initiates the cellular machinery to manufacture cyanotoxins. This unpredictability makes any bloom dangerous. Cyanotoxins are included in EPA s Contaminant Candidate Lists for future regulations but not the Unregulated Contaminant Monitoring Lists due to the lack of a reliable method. The lack of a method means that a comprehensive set of occurrence data does not exist. Without occurrence data, it is not possible to perform a Qualitative Health Risk Assessment to know where to set MCLs. Without an MCL for cyanotoxins, drinking water systems have no requirements to minimize exposure. Significance of no methods: WTPs are operating blindly, no consistent guidance is possible.

20 Increasing Nutrient Loading of N & P Unknown Impacts: Cyanobacteria (blue-green algae) Toxins Other common cyanobacteria toxins Saxitoxins Nodularins Cylindrospermopsin Anatoxin-a(s) Anatoxin-a The cyanobacteria Anabaena is a major producer of the above neuro toxins General structure of microcystin. There are at least 80 different variations to microcystins which vastly increase the complexity of analysis. The cyanotoxins are released when the cell lyses i.e., when the cell membrane breaks open and releases its contents Microcystins are extremely stable in water; they can persist for months or even years in cool, dark waters

21 Increasing Nutrient Loading of N & P Unknown Impacts: Health Impacts of Cyanobacteria (blue-green algae) Toxins Saxitoxins (neurotoxin) Blocks the flow of sodium ions, stopping the propagation of nerve impulses; muscle cells receive no stimulation and become paralyzed. Microcystins Causes the liver cells to shrink and separate, which causes the capillary cells to separate, causing blood to spill into the liver tissue. This bleeding quickly leads to death. The effects are the same for all species Anatoxin-a & a(s) (neurotoxins) Causes the muscles to contract and cannot return to their resting state. The muscles become exhausted, leading to paralysis of the muscles, dyspnea, shortness of breath, cyanosis, deoxygenation of the blood, and cardiac arrest. Cylindrospermopsin Liver toxicity, liver necrosis, kidney effects, gastrointestinal effects, and inhibition of protein synthesis. Cyanotoxins are highly potent: Anatoxin-a(s) has the same LD50 as cobra venom (20 ug/kg). LD50 is the dosage at which only 50% are expected to live. Saxitoxin is the most toxic at 9 ug/kg.

22 Increasing Nutrient Loading of N & P Unknown Impacts: Cyanobacteria (blue-green algae) Toxicity to Humans The World Health Organization (WHO) set a level of 1.0 ppb for microcystin LR the most common and well researched cyanotoxin. River Meadows, Bend, Colorado At about 20 times that level, 52 people died from an algal bloom when it was fed intravenously to dialysis patients and caused liver failure. That incident led to a disease named after the city it occurred in called Caruaru Syndrome a disease caused by cyanotoxins.

23 ncreasing Nutrient Loading of N & P Unknown Impacts: Can Cyanobacteria blue-green algae) Toxins be Treated? Micro or ultra filtration membranes Cells are effectively removed It depends if you re treating for cells or toxins If copper sulfate is not added If copper sulfate is added, it causes an immediate and massive release of the cyanobacteria toxins With typical treatment: Coagulation, sand filtration & chlorination Cyanotoxins are not effectively removed Silver Lake, Colorado With typical treatment: Coagulation, sand filtration, chlorination & powdered activated carbon Cyanotoxins are effectively removed but, its dependant on the dose, other organics, and bacterial growth With typical treatment: Coagulation, sand filtration, chlorination & UV or ozone Cyanotoxins are effectively destroyed for ozone but new organics are formed. UV is effective for toxins but new cells are inactivated only to lyse and release their toxins after UV Significance of treating: Capital improvements are needed, but WTPs are operating blindly. What should the strategy be: Treat for the cells? Treat for the toxins? Treat for cells first, then the toxins? No methods, lack of data, no consistent guidance.

24 Increasing Nutrient Loading of N & P Total Impacts of nutrient loading Clogged intakes Taste and odors ph fluctuations TTHM & HAA5 exceedances Clogged filters Switching to chloramine & NDMA Chlorine and CuSO4 resistant algae Cyanobacteria toxins With unknown levels of potent carcinogens, neuro and liver toxins, it is not possible to develop a comprehensive strategy for treating for the effects of nutrient loading. It is an overwhelming technical challenge for even the most sophisticated water treatment facilities.

25 A new national study by the U.S. Geological Survey reports that elevated concentrations of nitrogen and phosphorous, nutrients that negatively impact aquatic ecosystems and human health, have remained the same or increased in many streams and aquifers across the Nation since the early 1990 s.

26 Acknowledgements: H Kenneth Hudnell PhD Former EPA Researcher VP & Director of Science SolarBee Inc. In Summary Nutrients have a huge impact on drinking water treatment and a huge impact on public health We desperately need to collaborate.

27 For our break out sessions consider: In the microcosm of a City, the nutrient problem has been solved by having their WTP upstream of their WWTP. WTP WWTP WTP WWTP But in the macrocosm of multiple cities, the nutrient problem has not been solved and this is where we need to expand our collaboration and responsibility to the downstream user. Entertain all possible options.