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Bhandara Water Watch
Check dam / nala bund · cd-5 Sensor-witnessed nala flow medium confidence · medium

Check dam near Dhamani

cd-5 · 20.7788, 79.7537 · Lakhandur taluka · PIN 441910

Contributing catchment 33.73 km² · at a 3 m bund it impounds 1,706 thousand m³ over 195 ha · design monsoon yield 19,621 thousand m³ · soil HSG-D (clay 41%).

What it delivers · indicative

Impoundment
1,706 TCM
Irrigation
341 ha
Drinking (person-yrs)
31,020
Recharge
205 TCM

Indicative benefit at a 3 m bund (DEM area-capacity at 3 m bund) under standard norms (irrigation ~5 TCM/ha; drinking 150 lpcd). Recharge is limited on HSG-D clay (12% of storage). Actual yield varies with monsoon reliability, seepage and siltation.

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

1,706 thousand m³ of net-new water · 341 ha irrigable · 31,018 drinking person-years.

full design storage — no structure holds water here today.

Why this site

Priority
81
Strahler
4
Slope
2.4%
Catchment
33.73 km²
Runoff CN
89
Lineament
0 km/km²

Sited on an order-4 nala with a 33.7 km² contributing catchment and gentle grade — a nala/check dam impounds monsoon runoff on the clay lowlands where infiltration is low.

Seasonal water extent · dual-sensor

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

Radar (S1, 48 passes) fills the monsoon gap that cloud hides from optical (S2, 40 scenes). Radar peak vs summer low: 17.90 ha, a 17.9 ha annual draw-down — the storage renovation recovers.

Area-capacity (DEM, 30 m) · gross storage by bund height

2 m4603 m17064 m46675 m10901storage · thousand m³ (bars)submergence · ha (line)
Catchment
33.73 km²
Bed elevation
229 m
Design yield
19,621 TCM
Fill ratio @3 m
11.5×

Cross-witness & confidence — independent corroboration

Two sensors track together

Optical (S2) and radar (S1) rise and fall together with correlation r = 0.65 across 40 paired months. Absolute extents match 0% — they differ by sensor physics on a flowing nala, so the shared rhythm is the witness, not the magnitude.

Nala flow (new-build site)

No existing lake here — expected for a new structure. Sensors confirm a monsoon flow pulse in the nala; nearest mapped lake is 8,905 m away.

Land acquisition (submergence)

A 3 m bund would submerge 195 ha — the land to be acquired. Cost & consent scale with this.

Displacement witness — real building footprints

Settlement in footprint — major acquisition

In the submergence footprint

875

buildings within the 788 m design-submergence radius (195 ha pond at 3 m).

Nearest structure

39 m

to the closest mapped building.

Within 500 m

266

buildings in the influence ring.

The design submergence overlaps a settlement — this site would require major land acquisition and resettlement, or a lower bund. Not viable at this height without displacement.

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

Dhamani

502 m away · Lakhandur taluka · PIN 441910

Nearest landmark

Shri Laxmi Rice Mill

Schools within 2 km

3

nearest 654 m

Health within 2 km

6

nearest 309 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

+0.049

116 ha lost · 382 ha gained over 1,864 ha land

Built-up (NDBI) change

76.2 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.