References

Key resources used to develop DataStream features

Map Layers

Watershed boundaries delineated on DataStream are consistent with Water Survey of Canada Sub-Drainage Areas (WSCSDA). To understand how these watersheds relate to other drainage areas in Canada, including major river and ocean drainage areas, and lower order watersheds, see Statistics Canada’s  Standard Drainage Area Classification. These watersheds are also consistent with the work unit of the National Hydrographic Network.  

The Atlantic DataStream boundary comprises all sub-drainage areas within New Brunswick, Nova Scotia, Prince Edward Island, and Newfoundland and Labrador. Watersheds have not been clipped to provincial boundaries and in some cases overlap with Québec and the state of Maine.

Map Layer Sources

Contains information licensed under the Open Government Licence – Canada.

Natural Resources Canada (2016). National Hydro Network - NHN - GeoBase Series. (Dataset). Accessed on Open Government.

Transboundary watershed data extracted from a combined dataset for North America published by the Commission for Environmental Cooperation (CEC).

Commission for Environmental Cooperation (2011). North American Atlas – Basin Watersheds. (Dataset). Accessed on CEC.

Water Quality Guidelines 

DataStream displays national guidelines for the protection of aquatic life that are published by the Canadian Council of Ministers of the Environment (CCME) and the United States Environmental Protection Agency (US EPA).

We have compiled a Water Quality Guideline Summary Spreadsheet that lists all CCME and US EPA guidelines for the protection of aquatic life, their translation to DataStream characteristic names, corresponding equations (where applicable), and links to source/reference material for each guideline.  

Calculated Guidelines

The following table outlines all characteristics that use equations to determine their guidelines as well as the characteristic that these equations are dependent on. These calculated guidelines relate to freshwater guidelines only. To view the equations in their entirety, please see DataStream’s Water Quality Guideline Summary Spreadsheet.

Characteristics with Calculated Guidelines and Their Dependencies

Characteristic NameGuideline TypeGuideline PublisherCharacteristics used in calculating the guideline

Aluminum

Chronic

CCME

pH

Ammonia

Acute, Chronic

USEPA

pH, Temperature

Cadmium

Acute, Chronic

CCME

Total hardness

Cadmium

Acute, Chronic

USEPA

Total hardness

Chromium (III)

Acute, Chronic

USEPA

Total hardness

Copper

Chronic

CCME

Total hardness

Lead

Chronic

CCME

Total hardness

Lead

Acute, Chronic

USEPA

Total hardness

Nickel

Chronic

CCME

Total hardness

Nickel

Acute, Chronic

USEPA

Total hardness

Pentachlorophenol

Acute, Chronic

USEPA

pH

Silver

Acute

USEPA

Total hardness

Zinc

Acute, Chronic

CCME

Dissolved organic carbon, Total hardness

Zinc

Acute, Chronic

USEPA

Total hardness

Hardness Calculations and Conversions

Both US EPA and CCME guidelines contain equations that are hardness dependent. The hardness for these guidelines is expressed in ‘Total hardness’ with units of mg/l and speciation ‘as CaCO3’. ‘Hardness, Ca, Mg’ can also be used instead of ‘Total Hardness’ as they are synonymous.

When ‘Total hardness’, or ‘Hardness, Ca, Mg’ exists with either a different unit or speciation, the original value is multiplied by the corresponding conversion factor to obtain the standard units and speciation.

Hardness Conversion Table

Characteristic NameUnitConversion Factor

Total hardness

mg/L CaCO3

1

Total hardness

ppm CaCO3

1

Total hardness

mmol/L CaCO3

9.99E-03

Total hardness

mval/L (meq/L) CaCO3

2.00E-02

Total hardness

mg/L CaO

0.56029

Total hardness

German degrees (dH)

5.60E-02

Total hardness

French degrees (fH)

0.1

Total hardness

English degrees (e)

7.02E-02

Total hardness

gr/gal(US)

5.84E-02

If neither ‘Total hardness’ or ‘Hardness, Ca,Mg’ exists, ‘Total hardness’ can be calculated using the following equation and concentrations of ‘Magnesium’ (Mg2+) and ‘Calcium’ (Ca2+) in mg/l.

Total Hardness [CaCO3] = 2.497*[Ca2+] + 4.118*[Mg2+]

If neither ‘Total hardness’ or ‘Hardness, Ca,Mg’ exists, and both concentrations of ‘Magnesium’ (MG2+) and ‘Calcium’ (Ca2+) don’t exist, ‘Total hardness’ can be calculated using the following equations along with ‘Hardness, magnesium’ and ‘Hardness, calcium’ in mg/L.

Total Hardness [CaCO3] = ‘Hardness, magnesium’ + ‘Hardness, calcium

Finally, if none of the previous characteristics required are available, the ‘Total hardness’ can be calculated using the following equation and ‘Hardness, carbonate’ and ‘Hardness, non-carbonate’ in mg/L.

Total Hardness [CaCO3] = Hardness, carbonate + Hardness, non-carbonate

Water Quality Guideline Sources

Science Explainers

Coming soon.