IE of a corresponding WWTP catchment area should be reported in the polygons table in polyPop as well as in table sites in popServ.
Should it be reported in the measures table as well? But I guess a measure should be linked to a sample which is not necessarily the case for IE so reporting in measures table is maybe not the right place?
IE is for inhabitant equivalent. There are different means to calculate them. It can be from chemical measures of the wastewater or also based on population, connection to the sewage network/building occupation databases. We have the IE by municipality/wwtp (as a municipality can be covered by more than 1 WWTP).
IE can be aggregated at the WWTP level but it is also useful to store them by municipality/wwtp although I do not see how in the ODM
Thank you for clarifying! I’d hear the term “population equivalent” before for measuring the capacity of a wastewater treatment plant, but “inhabitant equivalent” was new to me.
It’s an interesting point you bring up, and I’d like to hear more of your perspective. As it stands, because polygons and sites can be many different kinds of areas or places, we don’t store capacity as metadata in those tables any longer since it would be empty very often. Instead, capacity is recorded as a site measure (like the ones from your question here: Where to report sites characteristic data).
In practice, this may look something like this (some columns removed for clarity):
Polygons:
Polygon ID
…
Name
…
Polygon Population
Geography Type
…
brxHlth01
…
Bruxelles Health Region
…
1,200,000
Health Region
…
bxlSewer01
…
Bruxelles Sewer catchment area 01
…
700,000
Sewer catchment Area
…
bxlSewer02
…
Bruxelles Sewer catchment area 02
…
500,000
Sewer catchment Area
…
Sites:
Site ID
…
Polygon ID
Site Type
Sample Shed
…
Name
…
Population Served
…
wwtpBRXnorth
…
bxlSewer01
Wastewater treatment plant
Municipality
…
WWTP Bruxelles Nord
…
700,000
…
wwtpBRXsouth
…
bxlSewer02
Wastewater treatment plant
Municipality
…
WWTP Bruxelles Sud
…
500,000
…
Measures:
Report ID
…
Polygon ID
Site ID
Dataset ID
…
Compartment
Specimen
…
Measure
Value
Unit
Aggregation
…
measRepX0
…
bxlSewer01
wwtpBRXnorth
wwBelgium
…
water
sample
…
covN1
0.00243
gc/mL
mean
…
siteRepX
…
bxlSewer01
wwtpBRXnorth
wwBelgium
…
water
site
…
WWTP Capacity
1,200,000
population equivalents
single
…
siteRepY
…
bxlSewer02
wwtpBRXsouth
wwBelgium
…
water
site
…
WWTP Capacity
1,500,000
population equivalents
single
…
I think with this example you can see how the site measures and the details on the sites and polygons can link together. But my question to you, and where I’d like to hear more of your input, is:
a) whether you this makes sense to you, and
b) if you think this is adequate for storing this kind of information.
If you think that it should be made a metadata header for sites again, I’m happy to hear that feedback as well. Let me know!
Thanks for your detailed answer. As for the IE by WWTP your proposal makes sense to me.
But I would also like to store them by WWTP/municipality (a municipality can be connected to multiple WWTPs and a WWTP can be connected to several municipalities so the raw data are x IE from this municipality going to this WWTP). I think it could be done by recording the IE by municipality/wwtp in the polygon table and link them to the corresponding wwtp in sites. But then if I want to make some aggregations of those IE at a provincial, regional or country level I would have to record the IE by province and region, country in the polygon table and select a different geotype.
With such a solution I would still need to keep somewhere outside the ODM which municipality belongs to which province and region unless having a parPolygonID in the polygon table maybe. It seems quite complex.
Thank you for this additional insight, and these really good points.
I think I’m following, and I believe I have a way of accomplishing what you’re wanting to using the current structure. I will say, though, that “parent polygon” or some other refactoring of polygon overlap, nesting, etc. is something we’ve discussed before and are considering for a version 3 (once version 2 is completely stable with the accompanying tools).
I think the solution to recording the IE at different levels (municipality, province, region, etc) is actually by using the sites table, and linking out to polygons where appropriate.
For example:
(I’ve left the GeoType as blank for some entries, but I think you’re right that we might need to release a patch with additional values, such as municipality, region, country, etc. - would also need to adjust sample shed for this)
Polygons:
Polygon ID
…
Name
…
Polygon Population
Geography Type
…
brxHlth01
…
Bruxelles-ville Health Region
…
189,000
Health Region
…
bxlSewer01
…
Bruxelles Sewer catchment area 01
…
700,000
Sewer catchment Area
…
bxlSewer02
…
Bruxelles Sewer catchment area 02
…
500,000
Sewer catchment Area
…
brx_reg
…
Région de Bruxelles-Capitale
…
1,200,000
NA
…
vlaams
…
Région flamande
…
6,774,807
NA
…
wallonne
…
Région wallonne
…
3,658,975
NA
…
belge
…
Royaume de Belgique
…
11,697,557
NA
…
Sites:
Parent Site ID
Site ID
…
Polygon ID
Site Type
Sample Shed
…
Name
…
Population Served
…
NA
belgique
…
belge
NA
country
…
Royaume de Belgique
…
11,697,557
…
belgique
flamande
…
vlaams
NA
Region
…
Région flamande
…
6,774,807
…
belgique
wallonne
…
wallonne
NA
Region
…
Région wallonne
…
3,658,975
…
belgique
regBRX
…
brx_reg
NA
region
…
Région de Bruxelles-Capitale
…
1,200,000
…
regBRX
villeBRX
…
brxHlth01
NA
Municipality
…
Bruxelles-Ville
…
189,000
…
regBRX
wwtpBRXnorth
…
bxlSewer01
Wastewater treatment plant
Municipality
…
WWTP Bruxelles Nord
…
700,000
…
regBRX
wwtpBRXsouth
…
bxlSewer02
Wastewater treatment plant
Municipality
…
WWTP Bruxelles Sud
…
500,000
…
Measures:
Report ID
…
Polygon ID
Site ID
Dataset ID
…
Compartment
Specimen
…
Measure
Value
Unit
Aggregation
…
measRepX0
…
bxlSewer01
wwtpBRXnorth
wwBelgium
…
water
sample
…
covN1
0.00243
gc/mL
mean
…
siteRepBRXnord
…
bxlSewer01
wwtpBRXnorth
wwBelgium
…
water
site
…
WWTP Capacity
1,200,000
population equivalents
single
…
siteRepBRXsud
…
bxlSewer02
wwtpBRXsouth
wwBelgium
…
water
site
…
WWTP Capacity
1,500,000
population equivalents
single
…
siteRepBRXreg
…
brx_reg
regBRX
wwBelgium
…
water
site
…
WWTP Capacity
2,700,000
population equivalents
mean
…
siteRepBelgNat
…
belge
belgique
wwBelgium
…
water
site
…
WWTP Capacity
9,500,000
population equivalents
mean
…
Do you think this sort of structure for maintaining aggregated capacity measures at the municipal, federal, etc. levels would work? Without then necessitating an external dataset?