2015 Shoal Lake water quality test results

Our staff test Shoal Lake and the intake at the west end of Indian Bay (where the water enters the aqueduct) as part of our routine water quality testing program.

For more information on Winnipeg's drinking water and our impact on Shoal Lake, visit the web page on Shoal Lake - Our Water Source.

Testing

We take samples at the intake every week during the open water season and every two weeks during the rest of the year. We also take samples from the Shoal Lake watershed from May to October. We test the intake samples for:

• routine water chemistry
• taste and odour compounds
• metals
• disinfection by-products
• bacteria and protozoa
• toxins produced by algae

By taking these samples, we track seasonal changes in water quality and determine the effects (if any) of human activity within the Shoal Lake watershed.

Water entering the aqueduct intake passes through screens before being treated by chlorine on a periodic basis for slime and Zebra mussel control. The aqueduct brings water to Deacon Reservoir before entering the Water Treatment Plant. There, we test both the raw and treated water before the water is distributed to Winnipeg homes and businesses.

Test results are from January 1 to December 31, 2015

What is being measured	How it's measured	Guideline or regulation	Shoal Lake average	Shoal Lake range	Comments
Odour	units	Inoffensive	136	75 to 200	Raw water - guideline does not apply
Perchlorate	parts per billion	no guideline	<0.2	<0.2 to <0.2	-
Plankton (algae) count	cells/mL	no guideline	22,315	900 to 113,700	Algae contribute to odours and may cause filter clogging
Chlorophyll-a	parts per billion	no guideline	8	<1 to 39	Chlorophyll is found in algae
Cryptosporidium	oocysts per 100 L	no guideline	0.6	<0.6 to 1.0	12 samples taken in 2015 - 1 positive result
Giardia	cysts per 100 L	no guideline	0.8	<0.6 to 3.3	12 samples taken in 2015 - 2 positive results
Turbidity (clearness)	NTU	no guideline	1.01	0.32 to 2.40	-
Colour, True	TCU	no more than 15 *	5.4	2.5 to 11.0	Raw water - guideline does not apply
Total Solids	parts per million	no guideline	122	88 to 202	-
Total Dissolved Solids	parts per million	no more than 500 *	104	69 to 150	Raw water - guideline does not apply
Conductivity	microsiemens per centimetre	no guideline	159	145 to 190	Another measure of dissolved solids
pH	units	between 6.5 and 8.5 *	8.16	7.68 to 8.81	Raw water - guideline does not apply
Temperature	degrees Celcius	no more than 15 *	11.6	1.0 to 22.5	Raw water - guideline does not apply
Total Alkalinity	parts per million as calcium carbonate	no guideline	74	66 to 90	-
Total Hardness	parts per million as calcium carbonate	no guideline	78	69 to 94	-
Total Organic Carbon	parts per million	no guideline	10	8 to 13	-
Dissolved Organic Carbon	parts per million	no guideline	9	7 to 13	-
Total Kjeldahl Nitrogen (TKN)	parts per million	no guideline	0.5	0.3 to 0.6	TKN is a combination of ammonia and organic nitrogen
Total Phosphorus	parts per billion	no guideline	16	8 to 23	Phosphorus can contribute to algae growth
Dissolved Reactive Phosphorus	parts per billion	no guideline	1	<1 to 3	-
Fluoride	parts per million	no more than 1.5	0.09	<0.08 to 0.13	Raw water - guideline does not apply
Nitrate Nitrogen	parts per million	no more than 10	0.014	<0.003 to 0.057	Raw water - guideline does not apply
Chloride	parts per million	no more than 250 *	2.5	1.5 to 4.6	Raw water - guideline does not apply
Sulphate	parts per million	no more than 500 *	<2	<2 to 2	Raw water - guideline does not apply
Trihalomethanes	parts per billion	no more than 100	<1	<1 to <2	Raw water - guideline does not apply
Bromodichloromethane	parts per billion	no guideline	<1	<1 to <1	-
Haloacetic acids	parts per billion	no more than 80	<3	<3 to 5	Raw water - guideline does not apply
Aldehydes	parts per billion	no guideline	4	1 to 8	-
Carbofuran	parts per billion	no more than 90	<0.20	<0.20 to <0.20	Raw water - guideline does not apply
Propoxur	parts per billion	no guideline	<0.20	<0.20 to <0.20	-
Aldrin	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
Lindane (gamma-BHC)	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
alpha-Chlordane	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
gamma-Chlordane	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
p,p-DDT	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
Dieldrin	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
Heptachlor	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
Heptachlor Epoxide	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
Methoxychlor	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
alpha-BHC	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
beta-BHC	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
delta-BHC	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
p,p-DDD	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
p,p-DDE	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
o,p-DDD	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
o,p-DDE	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
o,p-DDT	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
Alpha Endosulfan	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
Beta Endosulfan	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
Endrin	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
Mirex	parts per billion	no guideline	<0.010	<0.010 to <0.010	-
Simazine	parts per billion	no more than 10	<0.10	<0.10 to <0.10	Raw water - guideline does not apply
Alachlor	parts per billion	no guideline	<0.10	<0.10 to <0.10	-
Atrazine	parts per billion	no more than 5	<0.10	<0.10 to <0.10	Raw water - guideline does not apply
Metribuzin	parts per billion	no more than 80	<0.20	<0.20 to <0.20	Raw water - guideline does not apply
Azinphosmethyl	parts per billion	no more than 20	<0.10	<0.10 to <0.10	Raw water - guideline does not apply
Chlorpyrifos	parts per billion	no more than 90	<0.10	<0.10 to <0.10	Raw water - guideline does not apply
Diazinon	parts per billion	no more than 20	<0.10	<0.10 to <0.10	Raw water - guideline does not apply
Dimethoate	parts per billion	no more than 20	<0.10	<0.10 to <0.10	Raw water - guideline does not apply
Malathion	parts per billion	no more than 190	<0.10	<0.10 to <0.10	Raw water - guideline does not apply
Parathion	parts per billion	no guideline	<0.10	<0.10 to <0.10	-
Terbufos	parts per billion	no more than 1	<0.10	<0.10 to <0.10	Raw water - guideline does not apply
Methyl Parathion	parts per billion	no guideline	<0.10	<0.10 to <0.10	-
2,4-D	parts per billion	no more than 100	<0.050	<0.050 to <0.050	Raw water - guideline does not apply
2,4-DB	parts per billion	no guideline	<0.050	<0.050 to <0.050	-
2,4-DP	parts per billion	no guideline	<0.050	<0.050 to <0.050	-
2,4,5-T	parts per billion	no guideline	<0.050	<0.050 to <0.050	-
2,4,5-TP	parts per billion	no guideline	<0.050	<0.050 to <0.050	-
Bromoxynil	parts per billion	no more than 5	<0.020	<0.020 to <0.020	Raw water - guideline does not apply
Dicamba	parts per billion	no more than 120	<0.0060	<0.0060 to <0.010	Raw water - guideline does not apply
Dinoseb	parts per billion	no guideline	<0.050	<0.050 to <0.050	-
MCPA	parts per billion	no more than 100	<0.025	<0.025 to <0.025	Raw water - guideline does not apply
MCPB	parts per billion	no guideline	<0.050	<0.050 to <0.050	-
Mecoprop	parts per billion	no guideline	<0.050	<0.050 to <0.050	-
Picloram	parts per billion	no more than 190	<0.20	<0.20 to <0.20	Raw water - guideline does not apply
Trichlopyr	parts per billion	no guideline	<0.050	<0.050 to <0.050	-
Diclofop-methyl	parts per billion	no more than 9	<0.10	<0.10 to <0.10	Raw water - guideline does not apply
Eptam	parts per billion	no guideline	<0.20	<0.20 to <0.20	-
Propachlor	parts per billion	no guideline	<0.20	<0.20 to <0.20	-
Propanil	parts per billion	no guideline	<0.20	<0.20 to <0.20	-
Triallate	parts per billion	no guideline	<0.10	<0.10 to <0.10	-
Trifluralin	parts per billion	no more than 45	<0.030	<0.030 to <0.030	Raw water - guideline does not apply
Arochlor 1016	parts per billion	no guideline	0.025	<0.020 to <0.20	-
Arochlor 1221	parts per billion	no guideline	0.025	<0.020 to <0.20	-
Arochlor 1232	parts per billion	no guideline	0.025	<0.020 to <0.20	-
Arochlor 1242	parts per billion	no guideline	0.025	<0.020 to <0.20	-
Arochlor 1248	parts per billion	no guideline	0.025	<0.020 to <0.20	-
Arochlor 1254	parts per billion	no guideline	0.025	<0.020 to <0.20	-
Arochlor 1260	parts per billion	no guideline	0.025	<0.020 to <0.20	-
Calcium	parts per million	no guideline	19.4	17.7 to 22.9	Contributes to hardness
Magnesium	parts per million	no guideline	5.60	4.94 to 6.50	Contributes to hardness
Sodium	parts per million	no more than 200 *	2.09	1.89 to 2.50	Raw water - guideline does not apply
Potassium	parts per million	no guideline	1.20	1.06 to 1.41	-
Iron	parts per million	no more than 0.3 *	0.017	<0.008 to 0.055	Raw water - guideline does not apply
Copper	parts per million	no more than 1.0 *	0.0009	<0.0003 to 0.0082	Raw water - guideline does not apply
Lead	parts per million	no more than 0.010	<0.0004	<0.0004 to <0.0004	Raw water - guideline does not apply
Aluminum	parts per million	no more than 0.1	0.0040	0.0006 to 0.0130	Raw water - guideline does not apply
Antimony	parts per million	no more than 0.006	<0.0005	<0.0005 to <0.0005	Raw water - guideline does not apply
Arsenic	parts per million	no more than 0.010	0.0009	0.0006 to 0.0012	Raw water - guideline does not apply
Nickel	parts per million	no guideline	0.0005	0.0003 to 0.0009	-
Chromium	parts per million	no more than 0.05	<0.0007	<0.0007 to <0.0007	Raw water - guideline does not apply
Chromium VI	parts per billion	no guideline	<10	<10 to <10	-
Boron	parts per million	no more than 5	0.019	0.009 to 0.034	Raw water - guideline does not apply
Cadmium	parts per million	no more than 0.005	<0.0004	<0.0004 to <0.0004	Raw water - guideline does not apply
Manganese	parts per million	no more than 0.05 *	0.0087	0.0023 to 0.0224	Raw water - guideline does not apply
Uranium	parts per million	no more than 0.02	<0.0005	<0.0005 to <0.0005	Raw water - guideline does not apply
Zinc	parts per million	no more than 5.0 *	0.0021	<0.0005 to 0.0141	Raw water - guideline does not apply
Zirconium	parts per million	no guideline	<0.0005	<0.0005 to 0.0032	-
Mercury	parts per million	no more than 0.001	0.000003	<0.000001 to 0.000010	Raw water - guideline does not apply

Note: Where value is expressed as less than (<), the value is halved and used in the calculations, where value is expressed as greater than (>), the value is used in the calculations

* Aesthetic objective: These guidelines have an objective and not a maximum acceptable limit. These parameters should not impact the safety of the water to drink and there is no anticipated health risk for short-term exposures.

Guidelines from ‘Summary of Guidelines for Canadian Drinking Water Quality' by Health Canada, October 2014