Watersheds () August 24, 2017 16 / 30 A Watershed decomposition - - PowerPoint PPT Presentation

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Watersheds () August 24, 2017 16 / 30 A Watershed decomposition () August 24, 2017 17 / 30 Decomposition Objective: Divide the p1 A1 domain into R1 A2 p2 A4 A5 sub-domains, each of R2 reasonable size. A3 Select suitable points

SLIDE 1

Watersheds

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SLIDE 2

A Watershed decomposition

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SLIDE 3

Decomposition

A4 A5 p1 p2 R1 A2 A1 A3 R2

Objective: Divide the domain into sub-domains, each of reasonable size. Select suitable points and prepare differential watersheds. Reservoirs R1 and R2. Special points p1 and p2. A1 = WS(p1), A2, A3 = WS(R1) − A1 and so on. Catchment of R1 = A1 + A2 + A3. Catchment R2 = WS(R2) − Catchment(R1). Attributes of each Ai area, crops, soil, rainfall and so on.

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SLIDE 4

The Watershed

a small volumetric unit for analysis. includes static data such as

◮ geology ◮ wells and discharges

dynamic data such as:

◮ weather data

land and water use.

◮ farms, factories,

wells etc.

Demarcation Along ridge lines enclosing surface water flow.

Objective

Water Balance, Sustainable use, Planning Intervention design.

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SLIDE 5

Daregaon

83 90 126 39 58 68 66 53 85 139 74 4 69 26 2 97 59 70 24 1 27 99 146 43 100 60 44 65 49 136 52 111 29 89 87 164 75 46 77 57 157 56 104 131 152 55 96 116 35 174 163 36 47 48 177 81 50 180 17 73 151 173 23 32 31 30 67 40 162 179 172 164 119 125 64 72 117 181 129 63 41 142 162 187 185 71 62 127 143 148 54 178 120 124 37 21 76 128 78 19 155 183 20 34 141 106 138 150 173 161 175 84 107 135 42 149 105 160 93 165 156 171 91 167 118 145 144 79 88 92 131 132 109 51 170 114 186 153 61 188 98 159 94 137 134 22 166 168 101 16 121 123 103 122 9 112 5 179 18 15 115 158 12 162 38 140 3 130 165 184 75°29'0"E 75°29'0"E 75°28'0"E 75°28'0"E 75°27'0"E 75°27'0"E 20°5'0"N 20°5'0"N 20°4'0"N 20°4'0"N

.

Legend Lineament Drainage Village Gat No. High Priority Moderate Priority Low Priority Limited Scope (Good for Soil Conservation) 0.5 1 1.5 2 0.25 Kilometers

Source - GW Prospect Map RGDWM 2009-10

Groundwater Survey & Development Agency

Map Showing Prioritization for Artificial Recharge Distict - Aurangabad, Taluka:- Phulambri, Village - Daregaon () August 24, 2017 19 / 30

SLIDE 6

Daregaon

.

0.45 0.9 0.225 Kilometers

1:20,000 SCALE - ACTIONPLAN MAP (Watershed No:- GP-8/4/14)

PREPARED BY:: Maharashtra Remote Sensing Applications Centre,

Dept. of Planning,Nagpur,
Govt. of Maharashtra.

And GSDA,Pune DATA SOURCES:: Village Map:Directorate of Land Records Linaments/Dyke:Derived from SatelliteData MRSAC, Actionplan: MRSAC Contour 5mt:Derived from SRTM data MRSAC, Watershed -AISLUS & GSDA, Drainage:GSDA,Pune

Village-Daregaon ,Taluka -Fulambari, District -Aurangabad

Location Map

7 1 685 6 9 695 6 8 675 715 720 725 6 6 5 6 6 655 650 745 715 735 725 7 3 5 730

GP-8/ 04/14 GP-8/ 04/12

D a r e g a o n D a r e g a o n

83 90 126 39 58 68 66 53 85 139 74 4 69 26 2 97 59 70 24 1 27 99 146 43 100 60 44 65 136 177 52 81 111 29 50 180 17 89 87 164 73 151 75 77 57 157 56 104 131 40 152 164 119 55 96 116 117 41 35 162 187 185 143 174 37 163 36 19 155 183 20 34 106 173 175 105 47 48 49 173 46 23 32 31 33 30 67 162 179 172 125 64 72 181 129 63 142 71 62 127 148 54 178 120 124 21 76 128 78 141 138 150 161 84 107 135 42 149 160 93 165 156 171 91 167 118 145 144 79 88 173 92 131 132 109 51 170 114 186 153 61 188 98 159 94 137 134 22 168 166 101 16 121 123 103 182 122 9 112 5 133 179 15 18 113 169 115 158 7 12 162 38 29 140 3 13 108 130 165 158 184 28 147

75°29'0"E 75°29'0"E 75°28'30"E 75°28'30"E 75°28'0"E 75°28'0"E 75°27'30"E 75°27'30"E 75°27'0"E 75°27'0"E 75°26'30"E 75°26'30"E 75°26'0"E 75°26'0"E 20°5'30"N 20°5'30"N 20°5'0"N 20°5'0"N 20°4'30"N 20°4'30"N 20°4'0"N 20°4'0"N 20°3'30"N 20°3'30"N

PREPARED FOR:: Vasundhara Watershed Development Agency, Maharashtra, Pune-1 And Director of Soil and Water Conservation Maharashtra, Pune-1

Sillod Kannad Vaijapur Paithan GangapurAurangabad Fulambari Soegaon Khuldabad Soegaon Part of Jalna District Part of Vaijapur Bid Pune Nashik Solapur Satara Jalgaon Thane Yavatmal Gadchiroli Jalna Latur Amravati Sangli Nagpur Nanded Dhule Buldana Chandrapur Ratnagiri Raigarh Kolhapur Gondiya Osmanabad Nandurbar Sindhudurg Bhandara

Legend

Linaments/Dyke Contour 5 Meter Watershed Boundary Survey/Gat No. Boundary Village Boundary Drainage Line Treatment Gully Plug or LBS Earthen Nalla Bund/ Gabian Bandhara Nala Desilting/C.N.B./K.T. Area Treatment Dry land Agriculture/Contour Bunding/ Farmpond Afforestation/ Dry Land Horticulture/Plantation CCT/Deep CCT/WAT/Forest Pond Compartment Bunding/Graded Bunding/Fram Pond/Well Recharge River/ Waterbody Village Area Page Size:A1

JALYUKT SHIVAR ABHIYAN (2017-18)

In Map Show Existing Activities with Red Colour and Proposed Activities with Green Colour

(For Official Use Only)

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SLIDE 7

The mathematics, data, entities and quantities

0.0 20 0.2 18 16 0.4 14 0.6 12 0.8 10 X Z 1.0 8 6 2 1.2 4 6 4 8 10 1.4 12 2 Y 14 16 1.6 18 20 1.8 2.0

The DTM or DEM: terrain model/elevation model is a representation of the terrain in a particular area. Grids are where the base division in 2D is a grid of squares/triangles with a certain resolutions.

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SLIDE 8

The Digital Terrain/Elevation model

XY−Domain (xi,yi) zi Basic grid in the 2D-plane as an index set, with adjacency association of z-values for each point, to define 3D points, edges, triangles and adjacency.

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SLIDE 9

The Attributes and Computation

The DTM or DEM: terrain model/elevation model is a representation of the terrain in a particular area. Attributes of the DTM-soil, geology, land-use, land-cover. Regions-subsets of the DTM, to represent watersheds, flows, etc. Functions and Computations: to simulate various physical quantities and their dynamics.

◮ Infiltration : the process of rainwater moving down to

groundwater.

◮ Drainage lines : The development of streams due to rainfall. ◮ Surface flow : a composite model of surface flow of water and

infiltration which may include time to flow, movement of solids etc.

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SLIDE 10

Lets Compute Drainage

If a drop falls at point (i, j) then how does it move? We consider the 8-neighbours

f the point.

8−way adjacency

The flow gets distributed relative to the height differences. Here is an example: 1.1 1.5 1.6 1.3 1.4 1.7 1.3 1.3 1.5 Hypothesis: Only lower, and in proportion to the height differences. 3/6 1/6 1/6 1/6 And this continues recursively downwards.

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SLIDE 11

and Infiltration

The slope values (×10−3). 2.1 2.5 2.6 7.3 9.1 8.0 1.3 1.3 1.5 Hypothesis: Infiltration depends on slope. 0.1 0.09 0.09 0.2 0.2 0.15 More complicated models: moisture, daily rainfall, soil-thickness.

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SLIDE 12

Ikharicha pada

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SLIDE 13

Ikharicha pada

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SLIDE 14

Coming back-mywatershed

V−weirs Rain−gauges

Suppose that we have installed appropriate rain-gauges and V-notch weirs. Suppose that we have good geological and GW data. Can we achieve stating a water-budget for mywatershed? Likely not. Most natural phenomena too complicated to model. A good model will always have predictive value. Short-term: floods, crops. Long term: health of watershed.

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