Tank renovation near Umari
tank-2 · 21.0408, 80.0345 · Sakoli taluka · PIN 441802
Contributing catchment 451.73 km² · at a 3 m bund it impounds 633 thousand m³ over 45 ha · design monsoon yield 406,554 thousand m³ · soil HSG-C (clay 37%).
In plain words
A large tank near Umari (Sakoli) that both sensors track closely (correlation 0.86) — filling to ~140 ha each monsoon and drawing down hard by summer. As a renovation it displaces no one. The one caution: the land-change screen shows Umari building up around it, an encroachment signal.
What to build
Renovate — desilt and strengthen — but survey the encroachment against the tank boundary first.
Why here
The water evidence is strong and there is no new land to acquire; the risk is that rising construction silts the tank faster and can creep onto its bed.
How
Ground-check the built-up encroachment against the foreshore, then desilt, strengthen the bund and waste weir, and protect the boundary.
The delta — now vs after
Renovated and protected, it holds its monsoon fill far longer for Umari; left alone, siltation and encroachment keep shrinking it.
What it delivers · indicative
Live capacity from the observed satellite extent (142 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
≈ 1,224 thousand m³ of net-new water · 245 ha irrigable · 22,255 drinking person-years.
recovered draw-down (82 ha of 87 ha peak) x 1.5 m — the water it loses to summer today. The site already carries ≈85 thousand m³ into summer today — that is not counted; only the recovered draw-down is new.
Why this site
An existing water body — desilting and strengthening recovers lost storage at a fraction of new-build cost.
Seasonal water extent · dual-sensor
Radar (S1, 48 passes) fills the monsoon gap that cloud hides from optical (S2, 23 scenes). Radar peak vs summer low: 87.3 → 5.6 ha, a 81.6 ha annual draw-down — the storage renovation recovers.
Area-capacity (DEM, 30 m) · gross storage by bund height
Cross-witness & confidence — independent corroboration
Two sensors track together
Optical (S2) and radar (S1) rise and fall together with correlation r = 0.86 across 23 paired months. Absolute extents match 69% — a close magnitude match strengthens the read on an open water body.
Independent inventory (HydroLAKES)
No HydroLAKES polygon within 800 m (nearest 1,327 m) — likely seasonal water not in the global inventory; treat as unconfirmed.
Land acquisition (submergence)
A 3 m bund would submerge 45 ha — the land to be acquired. Cost & consent scale with this.
⚠ catchment likely includes a through-flowing nala — verify pour point
Displacement witness — real building footprints
No structures in footprintIn the submergence footprint
0
a renovation floods no new land — desilting restores depth within the existing waterspread, so nothing is displaced.
Nearest structure
185 m
to the closest mapped building.
Within 500 m
41
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
Umari
1,202 m away · Sakoli taluka · PIN 441802
Nearest landmark
Aasha Kiran Palace
Schools within 2 km
1
nearest 1,324 m
Health within 2 km
1
nearest 1,095 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)
Built-up rise (encroachment)Vegetation (NDVI) change
-0.02
249 ha lost · 71 ha gained over 1,757 ha land
Built-up (NDBI) change
245.2 ha
new built-up / bare (construction proxy)
Window
2022-11..2023-02 (8 scenes)
→ 2025-11..2026-02 (8 scenes)
Construction / encroachment is rising in the site vicinity — this changes runoff and raises future land-acquisition cost. Prioritise an early ground check.
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.