Perhitungan Debit Bulanan Metode F.J MOCK

Luas DAS 119 km2

K = 0.6

Tahun 1999 i 0.4

31 28 31

I Data Meteorologi

1 Hujan Bulanan Rata-Rata (P) mm/bulan 331.00 90.00 240.00

2 Hari Hujan Rata-Rata (n) hari 7.00 5.00 14.00

II Evapotranspirasi Potensial (Eto) mm/hari 4.27 5.29 4.98

mm/bulan 132.37 148.12 154.38

III Limit Evapotranspirasi

3 Exposed Surface (M) % 20% 20% 20%

4 E / ETo = (M / 20) x (18 - n) % 11% 13% 4%

5 E = Eto (M / 20) x (18 - n) mm/bulan 14.56 19.26 6.18

6 Evapotrans Aktual ( E1 = Eto - E ) mm/bulan 117.81 128.86 148.20

IV Water Balance 3.80 4.60 4.78

7 Water Surplus (P - E1) mm/bulan 213.19 -38.86 91.80

V Run Off & Ground Water Storage

8 Infiltrasi (i = 40%) 85.28 0.00 36.72

9 0,5 (1 + K)i K = 0,6 68.22 0.00 29.37

10 K (Vn - 1); 1st step 17.21 51.26 30.75

11 Vn = k(Vn - 1) + 0,5 (1 + k)i; 1st step 85.43 51.26 60.13

12 K (Vn - 1); 2nd step 53.23 83.20 80.67

13 Vn = k (Vn - 1) + 0,5 (1 + k); 2nd step 138.66 134.45 140.80

14 K (Vn - 1); 3rd step 121.02 123.87 105.08

15 Vn = k (Vn - 1) + 0,5 (1 + k)i; 3rd step 206.45 175.13 165.20

16 K (Vn - 1); 4th step 121.17 123.96 105.13

17 Vn = k (Vn - 1) + 0,5 (1 + k)i; 4th step 206.60 175.21 165.26

18 Volume air tanah (Vn) mm/bulan 206.60 175.21 165.26

19 Vn' = Vn - (Vn - 1) mm/bulan 4.65 -31.38 -9.96

20 Base Flow = i - Vn' 80.63 31.38 46.68

21 Direct Run Off mm/bulan 127.91 0.00 55.08

22 Run Off mm 208.54 31.38 101.75

23 Debit Bulanan Rata - Rata ltr/dt 9265 1544 4521

No. Keterangan Unit Jan Feb Mar

30 31 30 31 31 30 31 30 31

177.00 271.00 112.00 161.00 117.00 135.00 432.00 251.00 228.00

9.00 6.00 4.00 7.00 3.00 7.00 15.00 11.00 11.00

5.03 4.67 3.94 4.12 4.74 4.99 5.03 4.49 4.80

150.90 144.77 118.20 127.72 146.94 149.70 155.93 134.70 148.80

20% 20% 20% 20% 20% 20% 20% 20% 20%

9% 12% 14% 11% 15% 11% 3% 7% 7%

13.58 17.37 16.55 14.05 22.04 16.47 4.68 9.43 10.42

137.32 127.40 101.65 113.67 124.90 133.23 151.25 125.27 138.38

4.58 4.11 3.39 3.67 4.03 4.44 4.88 4.18 4.46

39.68 143.60 10.35 47.33 -7.90 1.77 280.75 125.73 89.62

15.87 57.44 4.14 18.93 0.00 0.71 112.30 50.29 35.85

12.70 45.95 3.31 15.15 0.00 0.57 89.84 40.23 28.68

36.08 29.26 45.13 29.07 26.53 15.92 9.89 59.84 60.04

48.77 75.22 48.44 44.21 26.53 16.48 99.73 100.07 88.72

84.48 79.95 93.10 84.93 77.48 62.41 47.33 88.24 112.98

133.25 155.17 141.54 129.14 104.01 78.89 147.06 188.31 201.70

99.12 88.74 98.37 88.09 79.38 63.54 48.01 88.65 113.23

147.90 163.96 146.82 132.30 105.91 80.02 147.74 188.72 201.95

99.15 88.76 98.39 88.10 79.38 63.55 48.02 88.65 113.23

147.93 163.98 146.83 132.31 105.91 80.03 147.74 188.72 201.95

147.93 163.98 146.83 132.31 105.91 80.03 147.74 188.72 201.95

-17.33 16.05 -17.15 -14.52 -26.40 -25.88 67.72 40.97 13.23

33.20 41.39 21.29 33.45 26.40 26.59 44.58 9.32 22.61

23.81 86.16 6.21 28.40 0.00 1.06 168.45 75.44 53.77

57.01 127.56 27.50 61.85 26.40 27.65 213.03 84.76 76.38

2617 5667 1262 2748 1173 1269 9465 3891 3394

Okt Nov DesApr Mei Jun Jul Agt Sep

Data CH Wilayah

Data CH Wilayah

Prhit. Eto

Data

((3) / 20) * (18 - (2))

(4) * (II)

(II) - (5)

(1) - (6)

i * (7)

0.5*(1+K)*(8)

K * (9D)dst

(9) + (10)

K * (11D) dst

(11) + (12)

K * (13D) dst

(11) + (14)

K * (15D) dst

(11) + (16)

(18) = (17)

(30J) - (30D) dst

(8) - (19)

(18) - (20)

(20) + (21)

(22) x CA / T

Ket.