IWMIHQ/east_africa_water_accounting

East Africa Water Accounting

Water accounting for East Africa at ~1060 m: rainfall, total ET, green and blue ET, water yield and runoff, each as a yearly average and split into dry and wet seasons, averaged over 2003-2021. Water Accounting Plus output rebuilt from IWMI's Africa GeoPortal tile services, which serve no downloadable raster.

• Region East Africa
• Period 2003-2021
• Theme Water accounting
• Grid EPSG:4326, 3108 x 3569 at 0.009521932 deg (~1060 m)
• Bands 18
• Files 18 Cloud-Optimised GeoTIFFs under data/, named <band>.tif, one per band

Bands

Band	Type	Units	Nodata
yearly_rainfall	float32	mm	-9999.0
yearly_et	float32	mm	-9999.0
yearly_rainfall_et	float32	mm	-9999.0
yearly_incremental_et	float32	mm	-9999.0
yearly_water_yield	float32	mm	-9999.0
yearly_runoff	float32	mm	-9999.0
dry_rainfall	float32	mm	-9999.0
dry_et	float32	mm	-9999.0
dry_rainfall_et	float32	mm	-9999.0
dry_incremental_et	float32	mm	-9999.0
dry_water_yield	float32	mm	-9999.0
dry_runoff	float32	mm	-9999.0
wet_rainfall	float32	mm	-9999.0
wet_et	float32	mm	-9999.0
wet_rainfall_et	float32	mm	-9999.0
wet_incremental_et	float32	mm	-9999.0
wet_water_yield	float32	mm	-9999.0
wet_runoff	float32	mm	-9999.0

Read it

These are COGs, so GDAL reads them in place over HTTP -- no full download, and a windowed read fetches only the bytes it needs:

from huggingface_hub import hf_hub_url
import rasterio

url = hf_hub_url("IWMIHQ/east_africa_water_accounting", "data/dry_et.tif", repo_type="dataset")
with rasterio.open(url) as src:
    print(src.width, src.height, src.crs, src.nodata)
    patch = src.read(1, window=((0, 256), (0, 256)))

Or pull the whole repo:

from huggingface_hub import snapshot_download
path = snapshot_download("IWMIHQ/east_africa_water_accounting", repo_type="dataset")

Read this before using it

A 2003-2021 AVERAGE, not a time series. No period is declared for this region anywhere -- not in a webmap title, an item description or the service metadata. The span given here is inherited from the sibling sets that DO declare one (Southern Region of Africa, and the continental set, both 2003-2021), on the assumption that these regional cuts come from the same processing run. Treat the period as an inference, not the publisher. Every cell is a multi-year mean, so no individual year is described and no trend can be read from it. Season months are undeclared. Nothing in the service metadata or the item records says where the dry season ends and the wet begins, so these bands cannot be aligned to a calendar or compared with another dataset's seasons. What is known is measured: the wet season averages 280 mm of rainfall against the dry season's 349 mm. The yearly bands are redundant rather than independent: dry + wet reproduces yearly to within 0.01439 mm, so agreement between them corroborates nothing. The exception is a scatter of individual bad cells: runoff breaks the sum in 2972 cells of 5656923, by up to 155 mm. Fewer than a hundredth of a percent, but mask aggressively if you difference the seasons against the yearly band. Dry-season water yield averages +30 mm and yearly +84 mm. Only 51.0% of the frame carries data -- the rest lies outside the mapped area -- so any whole-frame statistic is meaningless. Rebuilt from a tile cache rather than downloaded, so these values are whatever was published into the LERC pyramid, read at the pyramid level that matches the services' native resolution. The ArcGIS service named in each file's source tag remains the authority. The 18 source services do not report identical corner coordinates: they differ by up to 4e-06 degrees, about 445.28 mm on the ground -- 0.00042 of a pixel. The dataset declares the grid the majority agree on. Nothing is resampled; this is recorded only so the discrepancy is not rediscovered as a bug.

Provenance

Rebuilt from IWMI Africa GeoPortal ArcGIS image services, which serve no downloadable raster: they answer exportImage with HTTP 400 because their capabilities are Image,TilesOnly. The full-resolution grid was recovered by fetching every LERC tile at the pyramid level matching the service's own native resolution, decoding, and mosaicking. Each GeoTIFF carries the originating service in its source tag, and that service -- not this copy -- is the authority for its values.

The same product is indexed in IWMI's Open Data Cube, which is the route to its footprint, time extent and band metadata as STAC:

https://explorer-production-0070.up.railway.app/stac/collections/east_africa_water_accounting

Citation

International Water Management Institute (IWMI), East Africa Water Accounting. Published via the IWMI Open Data Cube. Licence CC-BY-4.0.

@misc{iwmi_east_africa_water_accounting,
  title        = {East Africa Water Accounting},
  author       = {International Water Management Institute},
  howpublished = {Hugging Face Hub, IWMIHQ/east_africa_water_accounting},
  note         = {Derived from IWMI Africa GeoPortal services; see Provenance},
  year         = {2026}
}