Lecture 4 Patterns of Water Demand By

Lecture 4 Patterns of Water Demand By : Eng. Mona Al-Gharbawi Eng. Ayman Al-Afifi

Patterns of Water Demand The water consumption varies hourly, daily, monthly and seasonally. This variation is caused by peoples activities that differs from one hour to another during the day , and by climate conditions. Demand Patterns are diagrams that show the variation of water consumption during a certain period of time. These diagrams are based on recordings for each type of water demand (Domestic, commercial, industrial … etc). Then the diagram is plotted between the time on the X axis and the ratio of the recorded flow to the average flow on the Y axis. Demand patterns for domestic consumption are usually generated using metric readings and billing records. For other types of demand studies are made to generate the demand patterns.

House information Residential Area Al Naser St. Source of water Beach Camp well (3) Duration of water supply Mostly (13: 00 -16: 00) House 2 floors Water recording Upper tanks No. of tanks 2 cold + 1 hot Family member 6 Description 2 College students, 2 school pupils Working Father Tank perimeter (m) Diameter (D) (m) Area m 2

Consumption Hour Q (litter ) 4 -6 6 -8 8 -10 10 -12 12 -2 2 -4 4 -6 6 -8 8 --10 10 --12 12 --2 2 --4 186 15 63 28 19 9 9 71 50 136 63 31

Cumulative Consumption Hour 4 -6 6 -8 8 -10 10 -12 12 -2 2 -4 4 -6 6 -8 8 --10 10 --12 12 --2 2 --4 Q (litter ) 186 201 264 292 311 320 329 400 450 586 649 680

Consumption = 6806 = 133. 3 lcd Average consumption 2 hours = = Hour Pattern Values 4 --6 3. 280 6 --8 0. 264 8 --10 1. 110 10 --12 0. 494 12 --2 0. 335 2 --4 0. 158 4 --6 0. 158 6 --8 1. 252 8 --10 0. 882 10 --12 2. 410 12 --2 1. 110 2 --4 0. 547

Factor Time ( hr )

Annual consumption Month January February March April May June July August September October November December Q ( m 3 ) 56 51 45 40 39 49 54 53 46 33 37 50

Annual pattern Month January February March April May June July August September October November December Pattern Values 1. 215 1. 106 0. 976 0. 868 0. 846 1. 063 1. 171 1. 150 0. 998 0. 716 0. 803 1. 085

Factor

ﻓﻨﺪﻕ ﻣﺼﻨﻊ ﺑﻼﻁ ﺯﺭﺍﻋﻲ )ﻃﻤﺎﻃﻢ( ﺯﺭﺍﻋﻲ )ﻓﺮﺍﻭﻟﺔ( ﻣﺪﺭﺳﺔ )ﻓﺘﺮﺗﻴﻦ( ﻣﺪﺭﺳﺔ )ﻓﺘﺮﺓ ﻭﺍﺣﺪﺓ( ﻣﺴﺠﺪ ﻣﺤﻄﺔ ﻭﻗﻮﺩ ﺍﻟﺘﺠﺎﺭﻱ ﺍﻟﺴﺎﻋﺔ 38. 0 0 41. 0 50. 0 00: 1 -00: 0 96. 0 0 12. 0 50. 0 00: 2 -00: 1 55. 0 0 0 6. 0 41. 0 12. 0 00: 3 -00: 2 94. 0 0 0 80. 2 82. 0 35. 0 00: 4 -00: 3 38. 0 0 0 6. 0 13. 0 47. 0 00: 5 -00: 4 9. 0 0 0 98. 0 52. 0 72. 1 00: 6 -00: 5 52. 1 70. 1 37. 3 91. 5 23. 1 82. 4 3. 0 82. 0 96. 1 00: 7 -00: 6 11. 1 17. 1 60. 7 20. 5 34. 2 21. 2 6. 0 82. 0 11. 2 00: 8 -00: 7 55. 0 17. 1 0 0 95. 1 89. 2 0 41. 0 11. 2 00: 9 -00: 8 24. 0 39. 1 0 0 68. 4 75. 2 0 82. 0 46. 2 00: 01 -00: 9 55. 0 41. 2 0 0 84. 1 4. 2 0 7. 0 61. 3 00: 11 -00: 01 96. 0 75. 2 0 0 73. 1 32. 2 3. 0 50. 1 23. 2 00: 21 -00: 11 40. 1 12. 3 0 0 10. 3 47. 2 74. 4 86. 1 85. 1 00: 31 -00: 21 52. 1 97. 2 0 0 93. 4 74. 2 17. 0 93. 2 73. 1 00: 41 -00: 31 35. 1 41. 2 0 0 60. 1 68. 0 0 18. 2 50. 1 00: 51 -00: 41 66. 1 41. 2 0 0 61. 1 86. 0 3. 0 93. 2 48. 0 00: 61 -00: 51 93. 1 39. 1 18. 3 42. 4 97. 0 43. 0 22. 3 21. 1 36. 0 00: 71 -00: 61 23. 1 46. 0 80. 7 91. 5 35. 0 43. 0 11. 2 24. 0 00: 81 -00: 71 64. 1 0 23. 2 63. 4 0 0 6. 0 93. 2 23. 0 00: 91 -00: 81 40. 1 0 0 0 75. 3 86. 1 23. 0 00: 02 -00: 91 93. 1 0 0 0 91. 1 12. 0 00: 12 -00: 02 11. 1 0 0 0 96. 3 48. 0 12. 0 00: 22 -00: 12 79. 0 0 0 3. 0 7. 0 11. 0 00: 32 -00: 22

Example ( 1 ) A water supply company delivered an average annual quantity of 10, 000 m³. On the maximum consumption day, the registered delivery was as follows : Hour 1 2 3 4 5 Q (m³/h) 989 945 902 727 844 13 14 15 16 17 1600 1309 1091 945 6 7 8 9 10 11 12 1164 1571 1600 1775 1964 2066 2110 18 19 20 21 22 23 24 1062 1455 1745 2139 2110 2037 1746 1018 Determine : The daily pattern for the water delivery of that area. The maximum seasonal variation factor for that day.

Solution : Find the average daily consumption = ∑ Q / 24 = 1454. 75 m³/hr For each hour, the pattern factor = Q / Qavg Hour 1 Q (m³/h) 989 Factor 0. 68 13 2 3 4 5 945 902 727 844 0. 65 0. 62 0. 58 0. 8 1. 08 1. 1 1. 22 1. 35 1. 42 1. 45 14 16 17 18 19 20 21 22 23 24 15 1600 1309 1091 1. 1 0. 9 0. 75 945 0. 65 6 7 8 9 10 11 12 1164 1571 1600 1775 1964 2066 2110 1062 1455 1745 2139 2110 2037 1746 1018 0. 73 1. 0 1. 2 1. 47 1. 45 1. 4 1. 2 0. 7

Factor Time ( hr ) The average consumption, based on the annual figure = 10, 000/365/24 = 1141. 55 m³/h. The seasonal variation factor = 1454. 75/1141. 55 = 1. 274.

Example ( 2 ) A water supply company delivers an annual volume of 13, 350, 000 m³. The maximum daily demand of 42, 420 m³ was observed on 26 July. The minimum, observed on 30 January, was 27, 360 m³. The following delivery was registered on 11 March: Determine: 1. Delivery on an average consumption day and the range of seasonal peak factors. 2. The Final peak factor diagram.

Solution : 1. /day Delivery on an average consumption day = Minimum seasonal Peak Factor = Maximum seasonal Peak Factor = Range of seasonal peak factors 0. 75 – 1. 16 2. To generate the peak factor diagram : Q avg = 1435 m³/hr , Ps = 1. 16 Hour 1 2 3 4 5 6 7 8 9 10 11 12 Factor 0. 35 0. 454 0. 52 0. 675 1. 172 1. 328 1. 553 1. 564 1. 525 1. 391 1. 383 13 14 15 16 17 18 19 20 21 22 23 24 1. 32 1. 338 1. 446 1. 555 1. 686 1. 661 1. 571 1. 174 0. 984 0. 657 0. 546 0. 486

Example ( 3 ) A Family of 7 members has the following Daily Consumption : Hour 0 1 2 3 4 5 6 7 8 9 10 11 Q (l/h) 25 15 7 5 5 11 34 15 14 25 70 53 12 13 14 15 16 17 18 19 20 21 22 23 47 67 95 103 57 34 38 25 23 19 15 19 And the following Annual Consumption : Month 1 Q (m³/d) 19. 7 2 3 4 5 6 7 8 9 10 11 12 18. 6 21. 5 23. 4 26. 9 35. 7 42. 4 45. 9 37. 5 32. 3 25. 4 20. 1 Generate the final demand pattern for 24 hrs.

Solution : Calculate the maximum monthly factor from the monthly pattern. The average monthly consumption = 29. 12 m³/d. Month 1 Q (m³/d) 19. 7 Factor 0. 68 2 3 4 5 6 7 8 9 10 11 12 18. 6 21. 5 23. 4 26. 9 35. 7 42. 4 45. 9 37. 5 32. 3 25. 4 20. 1 0. 64 0. 74 0. 80 0. 92 1. 23 1. 46 1. 58 1. 29 1. 11 0. 87 0. 69 So the monthly peak factor = 1. 58 Generate the pattern for daily consumption : Qavg= 34. 21 m 3/h Hour 0 Q (l/h) 25 Factor 1. 15 1 15 2 8 3 6. 5 4 5 5 11 6 34 7 15 8 14 9 25 10 70 11 53 0. 69 0. 37 0. 30 0. 23 0. 51 1. 57 0. 69 0. 65 1. 15 3. 23 2. 45 12 47 2. 17 13 67 3. 09 14 95 4. 39 15 103 4. 76 16 57 2. 63 17 34 1. 57 18 38 1. 76 19 25 1. 15 20 23 1. 06 21 19 0. 88 22 15 0. 69 23 19 0. 88

Example ( 4 ) For a given junction serves different average consumptions (Qave-2 h) and patterns. Calculate the total average consumption (Residential, Commercial & Agriculture) and combined pattern for this junction. Time (hour) 0 -2 2 -4 4 -6 6 -8 8 -10 10 -12 12 -14 14 -16 16 -18 18 -20 20 -22 22 -24 Residential (Qav=15 m 3/2 h) 0. 5 0. 3 0. 5 2 1. 5 1. 1 1. 2 2 1 0. 8 Commercial (Qav=3 m 3/2 h) 0 0. 8 1. 7 2. 5 3 1. 5 1. 2 0. 8 0. 5 0 Agriculture (Qav=10 m 3/2 h) 0 0 0 1 3 2. 4 0 2. 6 2 1 0 0

Time (hour) 0 -2 2 -4 4 -6 6 -8 8 -10 10 -12 12 -14 14 -16 16 -18 18 -20 20 -22 22 -24 Residential 0. 5 0. 3 0. 5 2 1. 5 1. 1 1. 2 2 1 0. 8 (Qav=15 m 3/2 h) 7. 5 4. 5 7. 5 30 22. 5 16. 5 18 30 15 12 16. 25 Commercial 0 0. 8 1. 7 2. 5 3 1. 5 1. 2 0. 8 0. 5 0 (Qav=3 m 3/2 h) 0 0 0 2. 4 5. 1 7. 5 9 4. 5 3. 6 2. 4 1. 5 0 3 Agriculture 0 0 0 1 3 2. 4 0 2. 6 2 1 0 0 (Qav=10 m 3/2 h) 0 0 0 10 30 24 0 26 20 10 0 0 10 Qav Total 29. 25 Qav • The Total average consumption = 29. 25 m³/2 hr Time (hour) 0 -2 2 -4 4 -6 6 -8 8 -10 10 -12 12 -14 14 -16 16 -18 18 -20 20 -22 22 -24 Residential 7. 5 4. 5 7. 5 30 22. 5 16. 5 18 30 15 12 Commercial 0 0 0 2. 4 5. 1 7. 5 9 4. 5 3. 6 2. 4 1. 5 0 Agriculture 0 0 0 10 30 24 0 26 20 10 0 0 Total Q 7. 5 4. 5 7. 5 42. 4 57. 6 48 24 47 41. 6 42. 4 16. 5 12 Equivalent Pattern Factor 0. 256 0. 154 0. 256 1. 450 1. 969 1. 641 0. 821 1. 607 1. 422 1. 450 0. 564 0. 410

Homework # 1 1. For Example ( 1 ), if an average leakage of 20 % is assumed. Find the daily pattern for the water consumption of that area.

Questions