Water Quality
Description
Water Quality data model is intended to represent water quality parameters at a certain water mass (river, lake, sea, etc.) section
Data Model
A JSON Schema corresponding to this data model can be found here.
-
id
: Unique identifier. -
type
: Entity type. It must be equal toWaterQualityObserved
. -
dateModified
: Last update timestamp of this entity.- Attribute type: DateTime
- Optional
-
dateCreated
: Entity's creation timestamp.- Attribute type: DateTime
- Optional
-
location
: Location where measurements have been taken, represented by a GeoJSON Point.- Attribute type:
geo:json
. - Normative References: https://tools.ietf.org/html/draft-ietf-geojson-03
- Mandatory if
address
is not present.
- Attribute type:
-
address
: Civic address where the Water Quality measurement is taken.- Normative References: https://schema.org/address
- Mandatory if
location
is not present.
-
refPointOfInterest
: A reference to a point of interest associated to this observation.- Attribute type: Reference to an entity of type
PointOfInterest
- Optional
- Attribute type: Reference to an entity of type
-
dateObserved
: The date and time of this observation in ISO8601 UTCformat. It can be represented by an specific time instant or by an ISO8601 interval. -
source
: A sequence of characters giving the source of the entity data.
Common water quality parameters
-
temperature
: Temperature. -
conductivity
: Electrical Conductivity. -
conductance
: Specific Conductance. -
tss
: Total suspended solids. -
tds
: Total dissolved solids. -
turbidity
: Amount of light scattered by particles in the water column. -
salinity
: Amount of salts dissolved in water. -
pH
: Acidity or basicity of an aqueous solution. -
orp
: Oxidation-Reduction potential.
Concentrations of chemical agents
This data model is flexible enough to accommodate different chemical agents present in water and which can be measured.
Applications MUST declare the list of chemical agents which concentration is being measured.
The measurand
attribute must be used for such purpose.
measurand
: An array of strings containing details (see format below) about extra measurands provided by this observation.- Attribute type: List of Text.
- Allowed values: Each element of the array must be a string with the following format (comma separated list of values):
<measurand>, <observedValue>, <unitcode>, <description>
, where:measurand
: corresponds to the chemical formula (or mnemonic) of the measurand, ex. CO.observedValue
: corresponds to the value for the measurand as a number.unitCode
: The unit code (text) of measurement given using the UN/CEFACT Common Code (max. 3 characters). For instance,M1
represents milligrams per liter.description
: short description of the measurand.- Examples:
"NO3,0.01, M1, Nitrates"
- Optional
Below there is a list of typical chemical agents measured when analysing water quality. If such chemical agents are measured
data providers MUST use the property names expressed by the following list. Nonetheless, the measurand
attribute
MUST be used to declare them, so that applications can discover what extra measurands are available as part of an observation.
-
O2
: Level of free, non-compound oxygen present. -
Chla
: Concentration of chlorophyll A. -
PE
: Concentration of pigment phycoerythrin which can be measured to estimate cyanobacteria concentrations specifically. -
PC
: Concentration of pigment phycocyanin which can be measured to estimate cyanobacteria concentrations specifically. -
NH4
: Concentration of ammonium. -
NH3
: Concentration of ammonia. -
Cl-
: Concentration of chlorides. -
NO3
: Concentration of nitrates.
Examples of use
{
"id": "waterqualityobserved:Sevilla:D1",
"type": "WaterQualityObserved",
"dateObserved": "2017-01-31T06:45:00Z",
"measurand": [
"NO3, 0.01, M1, Concentration of Nitrates"
],
"location": {
"type": "Point",
"coordinates": [ -5.993307, 37.362882 ]
},
"temperature" : 24.4,
"conductivity": 0.005,
"pH": 7.4,
"NO3": 0.01,
}