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Bhandara Water Watch
Tank desilting / strengthening · tank-10 Satellite-observed water body medium confidence · medium

Tank renovation near Wadad

tank-10 · 21.0334, 80.0165 · Sakoli taluka · PIN 441802

Contributing catchment 466.2 km² · soil HSG-C (clay 40%).

In plain words

A tank at Wadad (Sakoli) that the sensors agree on — filling in the monsoon, emptying by summer. Almost entirely clear; a single structure sits close to the water’s edge.

What to build

Renovate — desilt and strengthen; verify the one adjacent structure first.

Why here

The water evidence is good and corroborated; the only open question is the lone building near the tank.

How

Check the adjacent structure on the ground, then desilt and strengthen.

The delta — now vs after

Restored depth means Wadad’s tank holds longer past the monsoon — more assured irrigation and drinking, with only a minimal land question to settle.

What it delivers · indicative

Impoundment
1,241 TCM
Irrigation
248 ha
Drinking (person-yrs)
22,571
Recharge
149 TCM

Live capacity from the observed satellite extent (83 ha) x 1.5 m mean depth. Desilting restores the depth lost to siltation — the tank empties to near-nothing by summer today, so recovered depth means water held later and more recharge. Irrigation ~5 TCM/ha; drinking 150 lpcd. Actual yield varies with monsoon reliability, seepage and siltation.

Incremental over today · the net-new gain, from the 4-year record

1,237 thousand m³ of net-new water · 247 ha irrigable · 22,491 drinking person-years.

recovered draw-down (82 ha of 83 ha peak) x 1.5 m — the water it loses to summer today. The site already carries ≈4 thousand m³ into summer today — that is not counted; only the recovered draw-down is new.

Why this site

Water-body area
8 ha
Catchment
466.2 km²
Soil (HSG)
HSG-C
Clay %
40%
Runoff CN
100
Peak water
83 ha

An existing water body — desilting and strengthening recovers lost storage at a fraction of new-build cost.

Seasonal water extent · dual-sensor

2022-06
2022-06-070 ha · MNDWI
95 ha— S2 optical — S1 radar2022-062026-05

Radar (S1, 48 passes) fills the monsoon gap that cloud hides from optical (S2, 37 scenes). Radar peak vs summer low: 82.80.3 ha, a 82.5 ha annual draw-down — the storage renovation recovers.

Cross-witness & confidence — independent corroboration

Two sensors track together

Optical (S2) and radar (S1) rise and fall together with correlation r = 0.63 across 37 paired months. Absolute extents match 48% — a close magnitude match strengthens the read on an open water body.

Independent inventory (HydroLAKES)

No HydroLAKES polygon within 800 m (nearest 1,843 m) — likely seasonal water not in the global inventory; treat as unconfirmed.

Land acquisition (submergence)

Submergence not computed for this structure type.

Displacement witness — real building footprints

No structures in footprint

In the submergence footprint

0

a renovation floods no new land — desilting restores depth within the existing waterspread, so nothing is displaced.

Nearest structure

92 m

to the closest mapped building.

Within 500 m

43

buildings in the influence ring.

Restoring lost depth within the existing waterspread raises no new water level and acquires no new land, so no one is displaced. Verify bed encroachment on the historical spread on the ground before restoring the full level.

Overture Maps buildings 2026-05-20.0 (union of OSM / Google Open Buildings / Microsoft / Esri), Bhandara admin_code=506. A desktop displacement screen — precedes, not replaces, cadastral (7/12) verification.

Reconnaissance context & access — Ola + Google Places

Nearest habitation

Wadad

1,403 m away · Sakoli taluka · PIN 441802

Nearest landmark

Wadad Bus Stop

Schools within 2 km

2

nearest 619 m

Health within 2 km

2

nearest 693 m

Google Places (New) searchNearby + Ola Maps Places nearbysearch · reconnaissance-grade. Independent witness to the buildings displacement layer — dense amenities near a site corroborate high displacement. Does not replace cadastral 7/12 records, geotechnical bores or a level survey.

Human pressure — land-cover change (2022 → 2026)

Stable land cover

Vegetation (NDVI) change

+0.042

41 ha lost · 132 ha gained over 1,738 ha land

Built-up (NDBI) change

29.7 ha

new built-up / bare (construction proxy)

Window

2022-11..2023-02 (8 scenes)

2025-11..2026-02 (8 scenes)

Sentinel-2 L2A dry-season MEDIAN composites (2022-23 vs 2025-26), water-masked; NDVI+NDBI change screen — not cadastral or DEM cut/fill

DPR-grade desktop hydrology from Copernicus GLO-30 (30 m) + ISRIC SoilGrids + ESA WorldCover; water extent from Sentinel-2 L2A MNDWI (optical) and Sentinel-1 GRD VV radiometrically calibrated to σ⁰ (DN²/sigmaNought² from the product calibration LUT, GCP thin-plate-spline geocoded, open water at σ⁰ < −17 dB; thermal-noise floor not subtracted). A desktop assessment that precedes — not replaces — the statutory ground & geotechnical survey.