Insights for the water sector helping decision-makers move forward - - PowerPoint PPT Presentation

Insights for the water sector

helping decision-makers move forward

Canadian Water Network frames what is known and unknown in a way that usefully informs the choices being made.

cwn-rce.ca

• Human health
• Drinking water treatment plants
• Flora and fauna
• Recreational use
• Local economies

Algal Bloom Impacts

• A recurring issue for municipalities
• The severity, frequency & geographical

distribution are increasing

• Increases are driven by human activities

and climate change

• Difficult to determine extent and costs
• f algal blooms on a national scale

Algal Blooms in Canada

• Nutrients
• Light
• Temperature
• Water circulation
• Competition with and predation

by other organisms

• Salinity

Factors causing algal blooms

• Nutrients
• Light
• Temperature
• Water circulation
• Competition with and predation

by other organisms

• Salinity

Factors causing algal blooms

• Climate change
• Human activities

Factors exacerbating algal blooms

• Nutrients
• Light
• Temperature
• Water circulation
• Competition with and predation

by other organisms

• Salinity

Factors causing algal blooms

• Climate change
• Human activities

Factors exacerbating algal blooms

Complete understanding of local contributing factors + holistic management approach

Monica Emelko

Professor, University of Waterloo; Scientific Director, forWater

Webinar Speakers

Nandita Basu

Associate Professor, University of Waterloo; Lead, Lake Futures Project

Wendy Krkosek

Water Quality Manager Halifax Water

Managing Drinking Water Treatability Threats from Algal Proliferation from the Source to Plant Intake

Monica B. Emelko, PhD Civil & Environmental Engineering, UW Mike Stone, PhD Geography & Environmental Management, UW Kirsten Müller, PhD Biology, UW UldisSilins, PhD Renewable Resources, UA Managing Algal Blooms in Drinking Water using Watershed-Scale Approaches

• -CWN Webinar--

September 18, 2019

| 2

• Algae: not a taxonomic

descriptor

• Cyanobacteria: phylum of

bacteria

• Multiple concerns in drinking

water treatment Algae & Cyanobacteria in Drinking Water Sources

| 3

• Toxins
• Taste and odor
• Filter Clogging
• Interference in

coagulation

• Variability in source

water quality

• Increased DBP

formation potential Algae & Cyanobacteria: Treatment Concerns

| 4

Biostabilization: Increasingly variable source quality

“Cumulative impact” is the impact on the environment which results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions …Cumulative impacts can result from individually minor but collectively significant actions taking place over a period of time. Leslie Reid Council on Environmental Quality (CEQ Guidelines, 40 CFR 1508.7, issued 23 April 1971)

undisturbed riverbed riverbed biostabilization

+

post-disturbance nutrients + biofilm post-disturbance fine sediment

Physical Sediment Characteristics Percentage of total mid-chain branched saturated biofilm by PLFA Stone et al. (2014)

Critical Shear Consolidation Stress for Erosion Period for Erosion (Tc) Depth @ Tc

[day] [Pa] [mm]

Castle River 2 0.105 0.013 UNBURNED 7 0.141 0.008 14 0.165 0.014 Lynx Creek 2 0.120 0.336 BURNED 7 0.230 0.426 14 0.310 1.540

| 5

Biostabilization: Increasingly variable source quality

“Cumulative impact” is the impact on the environment which results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions …Cumulative impacts can result from individually minor but collectively significant actions taking place over a period of time. Leslie Reid Council on Environmental Quality (CEQ Guidelines, 40 CFR 1508.7, issued 23 April 1971)

undisturbed riverbed riverbed biostabilization

+

post-disturbance nutrients + biofilm post-disturbance fine sediment

Physical Sediment Characteristics Percentage of total mid-chain branched saturated biofilm by PLFA Stone et al. (2014)

Critical Shear Consolidation Stress for Erosion Period for Erosion (Tc) Depth @ Tc

[day] [Pa] [mm]

Castle River 2 0.105 0.013 UNBURNED 7 0.141 0.008 14 0.165 0.014 Lynx Creek 2 0.120 0.336 BURNED 7 0.230 0.426 14 0.310 1.540

| 6

Disturbances, Erosion, & Algal Proliferation

| 7

Disturbances, Erosion, & Algal Proliferation

| 8

Landscape Disturbance and Erosion

| 9

Cross section of reservoir bottom sediment sample

Surficial fine sediment

• light brown fluffy

biologically rich layer (3-5 mm) Consolidated fine sediment

• grey blue clay like materials
• anoxic

Importance of Fine Sediment Primary vector for P transport!

| 10

Phosphorus: Limiting Nutrient in Freshwater

McMahon (2013) DOI:10.1146/annurev-micro-092412-155713

| 11

Reservoir Sediment – M. aeruginosa Proliferation

Yang (2018) MASc Thesis

| 12

Land Use Change: Impacts on TSS and TP

| 13

Land Use Change: Impacts on TSS Headwaters Mixed Urban

| 14

Land Use Change: Impacts on TP Headwaters Mixed Urban

Al Alberta ta Sur urface Wa Wate ter Quality Guid uideline: : 50 50 µg/ µg/l CCM CME & Global Guid uideline: : 30 30 µg/ µg/l

| 15

Risk Management: BMPs for Erosion Control

Bahramian et al. (2018,2019)

| 16

Risk Management: Reservoir Management

| 17

Risk Management: Reservoir Management

| 18

Risk Management: Reservoir Dredging

| 19

• Algae are present in surface water year round:
• ur goal is to manage their proliferation
• Algal proliferation is complicated, BUT…..

management of bioavailable P makes it less likely

• Fine sediment is the primary vector for P transport in

aquatic systems and can serve as a key source of bioavailable P

• Fine sediment can comprise less than 1% of sediment

mass in a river and still carry more than 90% of the contaminant—including P—load! Key Messages

| 20

• Key sources of bioavailable P are frequently overlooked if

we only look in the water column!

• Upstream erosion control focused on fine sediment is a

key management strategy…in all environments

• Reservoir (and clarifier) management can include:
• Dredging
• P sequestration by coagulation
• Aeration to disturb algae and reduce P release

from fine sediments Key Messages

| 21

• SRWP: Chris Williams, Amanda Martens, Kalli Herlein,

Erin Cherlet (UA)

• Many students: especially Caitlin Watt, Jill Crumb &

Amy Yang (UW)

• Heather Roshon, Canadian Phycological Culture (UW)
• Norma Ruecker and Eric Camm (City of Calgary)
• Tim Walton (Region of Waterloo)

Acknowledgments

| 22

Partners

Thank you

Monica B. Emelko mbemelko@uwaterloo.ca

Nandita Basu Associate Professor University of Waterloo

Managing Algal Blooms

A Watershed Approach in the Lower Great Lakes Basins

Kimberly Van Meter, Phillipe Van Cappellen, Fred Cheng, Melani-ivy Samson

2 9/18/2019 Add a footer

LAKE ERIE

“A normal lake is knowable. A Great Lake can hold all the mysteries of an ocean, and then some.” –Dan Egan, Life and Death of the Great Lakes

3 9/18/2019 Add a footer

Lake Erie’s woes started in the 1960s

4 9/18/2019 Add a footer

Lake Erie’s woes started in the 1960s

Detergent bans and Wastewater Treatment Plant upgrades decreased Phosphorous loads and algal blooms

Detergent bans and Wastewater Treatment Plant upgrades decreased Phosphorous loads and algal blooms

7 9/18/2019 Add a footer

Algae in the News

Toledo Drinking Water Crisis

8 9/18/2019 Add a footer

Algae in the News

Toledo Drinking Water Crisis

Lake Futures: Enhancing Adaptive Capacity

and Resilience of Lakes and their Watersheds

• What is causing the

resurgence of the blooms?

• How do we achieve a 40%

reduction in phosphorus (P) export to Lake Erie?

• How LONG will it take?
• What are the costs and

benefits?

Lake Erie dominated by agricultural landscape – fertilizer and

manure are the two big contributors of P loads

Agriculture is LEAKY and excess runs off – we have been able to reduce this excess, but there is still legacy..

In urban areas, pet waste and urban fertilizer are significant sources of phosphorus to rivers and lakes

Fertilizer application rates on urban lawns three times higher than in agricultural areas

• 1.6 - -1.0
• 0.9 - 0.0

0.1 - 1.0 1.1 - 2.0 2.1 - 3.0 3.1 – 4.0

Normalized Rate of Change

Van Meter & Basu., in prep

The Role of Climate Change

Winter Flows are Increasing in Lake Erie Basin

Increasing winter flows bring in more dissolved (bioavailable) P

Total P = Dissolved P + Particulate P

Lake Futures: Enhancing Adaptive Capacity

and Resilience of Lakes and their Watersheds

What is causing the resurgence of the blooms?

• Fertilizer and Manure
• Legacy
• Climate Change
• Tillage, tile drainage

etc.

Recoupling the Nutrient Economy:

Manure recycling on cropland and biogas plants

Recoupling the Nutrient Economy:

Manure recycling on cropland and biogas plants

Nutrient Legacies build up in soils and groundwater and delay water quality improvement

adapted from Reddy et al.(2011)

If P is building up soils can we effectively “harvest” it?

YES – We can dramatically reduce P application rates and improve water quality without affecting crop yield

If P is building up soils can we effectively “harvest” it?

YES – We can dramatically reduce P application rates and improve water quality without affecting crop yield

Cover Crops

How long will it take for water quality to improve?

We develop models to answer these questions…

Runoff Erosion

Phosphorus Surplus (crop litter, manure, P fertilizer, atm dep Organic P

Active Protected

Mineral P Phosphorus Surplus (crop litter, manure, P fertilizer, atm dep

Source Zone

Wastewater Effluent

Retention (Reservoirs and Riparian Zones

Phosphorus Loading at the Catchment Outlet

How long will it take to improve water quality at the watershed scale?

To achieve the required 40% reduction in P load, we need a 100% reduction in P surplus and 50% WWTP upgrades It will take 25 years to achieve this

What if you want faster results? Transport BMPs Grassed Waterways Riparian Buffers Wetlands Reservoirs

Wetland Restoration…

Southern Ontario has lost as much as 66%

• f its wetlands in

the last few decades

What wetland restoration targets will help achieve 40% P load reduction? Which wetland and where within the watershed should wetland restoration be prioritized?

What wetland restoration targets will help achieve 40% P load reduction? Which wetland and where within the watershed should wetland restoration be prioritized?

The Role of Reservoirs

Can we manage reservoirs to

IMPROVE

downstream water quality?

Managing Algal Blooms

Recognize lag times and adjust expectations

Managing Algal Blooms

Recognize lag times and adjust expectations Nutrient Management

Reduce P Surplus

Managing Algal Blooms

Recognize lag times and adjust expectations Nutrient Management

Reduce P Surplus

Spatially and temporally targeted measures

Managing Algal Blooms

Recognize lag times and adjust expectations Nutrient Management

Reduce P Surplus

Spatially and temporally targeted measures Downstream Controls: Wetlands and Reservoirs

Managing Algal Blooms

Recognize lag times and adjust expectations Nutrient Management

Reduce P Surplus

Spatially and temporally targeted measures Downstream Controls: Wetlands and Reservoirs Thank you Twitter: @nanditabasu2 Email: nandita.basu@uwaterloo.ca

Lake Recovery and Impacts on Water Treatment

Wendy Krkosek, Ph.D., P.Eng. Water Quality Manager, Halifax Water Co-authors: Sanjeev Tagra, Lindsay Anderson, Dr. Graham Gagnon

CWN Webinar Sept 18, 2019

Sulphur Dioxide Emissions in North America

Data source: earthobservatory.nasa.gov

2006 Ultra Low Sulphur Diesel

• reg. Can/US

2012 Marine Fuels Sulphur from 3.5 to 1% 2015 US Clean Power Plan introduced 2030 Canada phases out coal plants 2005-2007 2011-2014

Lake Recovery from Acidification

• Reduced sulphate deposition leads to “recovery” defined by increasing acid

neutralization capacity, alkalinity/pH, natural organic matter and changes to biological structure in lakes

10 20 30 40 50 60 ppb

Source: https://data.novascotia.ca/Environment-and-Energy/Nova-Scotia-Provincial-Ambient-Sulphur-Dioxide-SO2/d2tu-gr6x

Environment Canada data

Long Term Chemical Trends 30+ years

Reference: Redden, D. 2019 Lake Recovery in Nova Scotia: A Longitudinal Review of Water Chemistry Data. MASc Thesis, Department of Civil & Resources Engineering, Dalhousie University, Halifax, NS

4

Source Water Changes at Halifax Water

Halifax Water Sources

6

Geosmin

• First occurrence in 2012
• Two sessions of source tracking: no

smoking gun

• No removal through treatment process
• Investigated treatment options
• Identified Lake Recovery concept in

2015 and moved towards a more holistic approach to robust and resilient treatment strategies

10 20 Aug-12 Aug-13 Aug-14 Aug-15 Aug-16 Aug-17 Aug-18 Aug-19

Treated Geosmin (ng/L)

Treatment Challenges at JD Kline a direct filtration facility

Parameter 1992-1993 Waller et al. 1996 2015 Plant Records Direct Filtration Design Guidelines

Color (TCU) 5 to 9 21 (max 42) < 20 TOC (mg/L) ~2.2 ~3.5 < 4 Alum Dose (mg/L) <8 12 2 to 10

Treatment selection for particle and NOM removal

Reference: Valade et al., (2009) Journal of Water Supply Research and Technology. 58(6): 424-432

June 2018 - Decreasing Filter Runtimes

20 40 60 15-May 22-May 29-May 5-Jun 12-Jun 19-Jun 26-Jun 3-Jul 10-Jul 17-Jul Hours Filter 1

10

Diatom Bloom

• The issue: Tabellaria fenestrata forming chains

which affects floc formation and removal

• Floc unable to penetrate filter
• Backwash regime unable to remove heavy

material

• Potential growth of organisms within the plant
• Result: increased headloss and reduced filter

run time

• Average filter run: 35-40 ML produced

and backwash 1-2 filters per day

• At height of incident: 8-9 ML produced

and all 8 filters backwashed daily

• Why such an issue at JD Kline?
• Only oxidation is permanganate
• Direct filtration: Limit for mass loading to

filters

• Backwash: no air scour to remove mass

100 200 300 400 500 0-2 2-6 6-12 12-18 18-24 24-30 30-36 ug Tabellaria/g of media Depth of filter media

200 400 600 800 1000 1200

ug/m3

4-Jul 11-Jul 19-Jul 24-Jul 31-Jul 7-Aug 13-Aug 28-Aug 4-Sep 18-Sep

11

Algae throughout the summer

200 400 600 800 1000 1200

ug/m3

4-Jul 11-Jul 19-Jul 24-Jul 31-Jul 7-Aug 13-Aug 28-Aug 4-Sep 18-Sep

12

Algae throughout the summer

10 20 30 40 50 60 70 15-May 22-May 29-May 5-Jun 12-Jun 19-Jun 26-Jun 3-Jul 10-Jul 17-Jul 24-Jul 31-Jul 7-Aug 14-Aug 21-Aug 28-Aug Filter Run Hours

200 400 600 800 1000 1200

ug/m3

4-Jul 11-Jul 19-Jul 24-Jul 31-Jul 7-Aug 13-Aug 28-Aug 4-Sep 18-Sep

13

Algae throughout the summer

10 20 30 40 50 60 70 15-May 22-May 29-May 5-Jun 12-Jun 19-Jun 26-Jun 3-Jul 10-Jul 17-Jul 24-Jul 31-Jul 7-Aug 14-Aug 21-Aug 28-Aug Filter Run Hours

Pre-Chlorine added

Treatment challenges at Lake Major

Reference: Anderson et al. (2017) Lake Recovery Through Reduced Sulfate Deposition: A New Paradigm for Drinking Water Treatment. Environmental Science & Technology 51(3) :1414-1422

Treatment challenges at Lake Major

Reference: Anderson et al. (2017) Lake Recovery Through Reduced Sulfate Deposition: A New Paradigm for Drinking Water Treatment. Environmental Science & Technology 51(3) :1414-1422

Hurricane Juan

Lake Recovery Impacts on Water Treatment

Source Water Changes

• Increased acid neutralization capacity,

alkalinity

• Increased organics, colour and change in
• rganics character
• Cyanobacteria and algae blooms
• Uncertainty in future water quality

Treatment Process Impacts

• Higher chemical dosages
• Lower production efficiency
• Additional treatment processes

may be required

• Increased risk of non-compliance

Distribution System Impacts

• Increased DBPs
• Taste & Odor
• Maintenance of disinfection

residual

• Increased corrosion impacts

17

Response to Source Water Changes

• Moving from reactive to proactive
• Filling data gaps
• Culture shift
• changing historical operations to

ensure quality of finished water

• Planning for the unknown
• What is the water quality

trajectory?

• What is appropriate design for

changing source water?

From Hazen: WRF 4920 kickoff workshop

18

WRF 4920 – Tailored Collaboration

Decision Support Framework for Drinking Water Treatment Plants Experiencing Lake Recovery

• Team
• PI: Hazen and Sawyer
• Utilities: Tampa Bay, New York City,

Mohawk Valley, Brick Township

• Tech advisors: Jim Edzwald, Charley

Driscoll, Franke Browne

• Timeline: Sept 2019 to May 2020
• End goal:
• Development of a decision support

framework for a source to tap treatment strategy to assess options for responding to changing source water quality in the near term and long term

19

Specific HW Strategies and Initiatives

Source water

• Enhanced source water

monitoring

• Continuous algal monitoring

at intakes

• Algal toxin monitoring

framework

• Intake investigation
• In-lake treatment options

Treatment

• Short term
• Robustness of existing

process

• Low-hanging fruit
• Continuous

improvement

• Filter replacement and

new filter standards

• Long term
• Process upgrades
• Resilience and

interconnectedness

20

Wendy Krkosek

Water Quality Manager wendyk@halifaxwater.ca