Assessment of reservoir sedimentation using remote sensing and recommendations for desilting Patratu Reservoir, India

Figures & data

Figure 1. Index map of the study area.

Table 1. Elevation–area–capacity of Patratu Reservoir.

Elevation (ft)	Elevation (m)	Difference in elevation (m)	Area (Acre)	Area (km^2)	Cumulative capacity (hm^3)
1223	372.75	0.00	0	0.00	0.0
1240	377.93	5.18	25	0.10	0.3
1250	380.98	3.05	131	0.53	1.2
1260	384.03	3.05	300	1.21	3.9
1270	387.08	3.05	504	2.04	8.8
1272	387.69	0.61	553	2.24	10.1
1280	390.12	2.44	689	2.79	16.3
1290	393.17	3.05	852	3.45	25.8
1300	396.22	3.05	1225	4.96	38.6
1310	399.27	3.05	1567	6.34	55.8
1320	402.32	3.05	1932	7.82	77.4
1330	405.36	3.05	2290	9.27	103.4
1332.5	406.13	0.76	2450	9.91	110.7

Figure 2. Original elevation–area–capacity curve of Patratu Reservoir.

Table 2. Satellite data for different dates of pass for the Patratu Reservoir w.r.t. water levels.

Date of satellite pass	Satellite/Sensor/Scene	Path	Row	Water level (m)
22 April 2006	IRS P6/LISS -III	105	55	390.876
16 January 2006	IRS P6/LISS -III	105	55	393.878
14 May 2011	IRS P6/LISS -III	105	55	397.596
27 March 2011	IRS P6/LISS -III	105	55	398.877
21 December 2010	IRS P6/LISS -III	105	55	400.629
8 May 2012	IRS P6/LISS -III	105	55	403.342
2 February 2012	IRS P6/LISS -III	105	55	405.216
29 October 2011	IRS P6/LISS -III	105	55	405.902

Figure 3. (a) False colour composite of Patratu Reservoir (22 April 2006) near MDDL, (b) extracted water spread areas of Patratu Reservoir near MDDL (22 April 2006), and (c) NDWI map of Patratu Reservoir near MDDL (22 April 2006).

Figure 4. (a) False colour composite of Patratu Reservoir (29 October 2011) near FRL, (b) extracted water spread areas of Patratu Reservoir (29 October 2011) near FRL, and (c) NDWI map of Patratu Reservoir (29 October 2011) near FRL.

Table 3. Patratu Reservoir capacity loss estimation due to sedimentation.

Elevation (m)	Elevation difference (m)	WS area (10^6 m^2)		Capacity (hm^3)		Cumulative capacity (hm^3)		Sediment deposition (hm^3)	Remarks
		Base year	2012 (SRS)	Base year	2012 (SRS)	Base year	2012 (SRS)	2012 (SRS)
387.096	0.000	2.05	2.040	0.00	0.00	0.00	0.00	0.00	MDDL
390.876	3.780	2.95	2.332	9.40	8.26	9.40	8.26	1.14
393.878	3.002	3.80	3.213	10.10	8.29	19.50	16.55	2.95
397.596	3.719	5.58	5.181	17.33	15.46	36.83	32.01	4.82
398.877	1.280	6.16	5.666	7.52	6.94	44.35	38.95	5.40
400.629	1.753	7.00	6.246	11.52	10.43	55.87	49.38	6.49
403.342	2.713	8.31	7.394	20.74	18.48	76.61	67.86	8.75
405.216	1.875	9.20	8.091	16.40	14.50	93.01	82.36	10.65
405.902	0.686	9.72	8.115	6.49	5.56	99.50	87.92	11.58
406.152	0.250	9.91	8.220	2.45	2.04	101.95	89.96	11.99	FRL

FRL: full reservoir level, MDDL: minimum draw down level, SRS: satellite remote sensing.

Figure 5. Comparison of elevation–capacity curves of Patratu Reservoir.