Identification

Title

Global dilution factors for domestic wastewater in rivers

Abstract

The dataset captures the temporal and spatial variability of dilution factors (DFs) around the world using geographically referenced data sets at 0.5 degree resolution and includes long term annual and monthly DFs grids. The dilution factor (DF) dataset is composed of 13 rasters: 1 annual and 12 monthly. DFs are a critical component in estimating concentrations of 'down-the-drain' chemicals which enter freshwaters following consumer use via the domestic waste water stream (e.g., pharmaceuticals, household cleaning products). The DF is defined as the ratio between flow and total domestic wastewater effluent generated within a catchment. The methodology was specifically developed to be applied across the world even within those countries where river flow data and/or wastewater effluent data is scarce. The present dataset has potential for a wide international community (including decision makers and pharmaceutical companies) to assess relative exposure to 'down-the-drain' chemicals released by human pollution in rivers and, thus, target areas of potentially high risk.

Resource type

dataset

Resource locator

http://eidc.ceh.ac.uk/metadata/42044391-a041-4884-bed7-67f67490224f/zip_export

name: Supporting Information

description: Supporting information available to assist in re-use of this dataset.

function: information

https://catalogue.ceh.ac.uk/download?fileIdentifier=42044391-a041-4884-bed7-67f67490224f

name: Download the data

description: Get a copy of this data

function: order

Unique resource identifier

code

https://catalogue.ceh.ac.uk/id/42044391-a041-4884-bed7-67f67490224f

codeSpace

doi:

Dataset language

eng

Spatial reference system

authority code

urn:ogc:def:crs:EPSG

code identifying the spatial reference system

4326

Classification of spatial data and services

Topic category

inlandWaters

Keywords

Keyword set

keyword value

Hydrography

originating controlled vocabulary

title

GEMET - INSPIRE themes, version 1.0

reference date

date type

publication

effective date

2008-06-01

Keyword set

keyword value

Dilution factor

down-the-drain chemicals

catchment

rivers

exposure

environmental risk assessment

PEC

modelling

Keyword set

keyword value

Modelling

Pollution

Water quality

Geographic location

West bounding longitude

-180

East bounding longitude

180

North bounding latitude

South bounding latitude

-55.5

Temporal reference

Temporal extent

Begin position

2013-12-31

End position

Dataset reference date

date type

publication

effective date

2014-07-11

date type

creation

effective date

2013-12-31

Frequency of update

notPlanned

Quality and validity

Lineage

The river flow was derived from the 0.5° resolution annual and monthly composite runoff fields produced by Fekete et al. (http://www.compositerunoff.sr.unh.edu/). These long term average runoff values were estimated across the globe by combining a simple water balance model and observed river discharge data. The monthly and annual runoff are accumulated using a topographically-derived flow direction grid to produce river flows at a 0.5° resolution. The domestic wastewater effluent was obtained by combining population estimates and per capita domestic water use estimates (national estimates). Population estimates were based on the GPW (Gridded population of the world) v.3 data set for 2005 at 0.5° resolution (http://sedac.ciesin.columbia.edu/data/set/gpw-v3-population-count-future-estimates). Four main data sources (public domain) for national per capita domestic water use were used: i) Gleick (2009), ii) Food and Agriculture Organisation (http://www.fao.org/nr/water/aquastat/main/index.stm), iii) World Resource Institute, iv) Organisation for Economic Co-operation and Development (http://www.oecd.org/env/indicators-modelling-outlooks/oecdenvironmentaldatacompendium.htm). Where discrepancies arose in domestic water use data, only the data for the year 2000 or later was retained, and from these the lowest estimate was selected to provide a more conservative value for the DF. These selected national estimates were then used to derive a 0.5° resolution grid of domestic water use.

Conformity

Data format

name of format

Esri ASCII GRID

version of format

Unknown

Constraints related to access and use

Constraint set

Use constraints

Dilution factor values along the coastlines must be handled with care due to higher uncertainty in accounting for population discharging to sea rather than rivers.

Constraint set

responsible party role

publisher

Metadata on metadata

Metadata point of contact

organisation name

Environmental Information Data Centre

full postal address

Lancaster Environment Centre, Library Avenue, Bailrigg

Lancaster

LA1 4AP

email address

eidc@ceh.ac.uk

responsible party role

pointOfContact

Metadata date

2018-10-17T12:07:26

Metadata language

eng