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Institutional Resilience

Climate Resilient Structures

Ensuring sustainable water infrastructure through rigorous hydrological analysis and adaptive engineering in Balochistan.

Climate Adaptation Strategy

The Balochistan Water Resources Development Sector Project (BWRDSP), financed under ADB Loan 3700-PAK (COL), is a flagship project of the Government of Balochistan to improve water security in the Zhob and Mula River basins.

The catastrophic monsoon events of 2022 and 2024 provided a test for the project. Despite rainfall reaching 239% above normal in Balochistan and 318% above normal in Sindh in 2024, BWRDSP schemes withstood flood discharges nearly 70% above their original design capacity, confirming their climate resilience.

Flood Resilience Capacity to safely pass ~60,000 cusecs in 2024 despite being designed for ~35,000 cusecs.
Drought Resilience Infiltration galleries at Killi Sardar, Hitachi, and Kharzan Churri, which recharge aquifers and ensure water availability during extended dry periods.
Climate Resilient Infrastructure
Resilience Study: Impact of 2024 Monsoon Floods

2. Hydrological Analysis and Flood Magnitudes

2.1 Rainfall Frequency Analysis (Updated 2022)

Table 1: Updated Rainfall Depths – Khuzdar Station
Return Period (yrs) Depth (mm, 1980–2018) Depth (mm, 1980–2022) % Increase
10 56.1 60.9 +8.5%
50 73.6 81.5 +10.7%
100 81.0 90.3 +11.5%
500 98.1 110.4 +12.5%
Table 2: Updated Rainfall Depths – Kalat Station
Return Period (yrs) Depth (mm, 1971–2018) Depth (mm, 1971–2022) % Increase
10 57.1 60.6 +6.1%
50 82.3 89.4 +8.6%
100 93.0 101.6 +9.2%
500 117.6 129.7 +10.3%

2.2 Design Flood Estimates for Key Schemes

Scheme 1:50 Yr (cusecs) 1:100 Yr (cusecs) 1:500 Yr (cusecs) 1:1000 Yr (cusecs) PMF (cusecs)
Siri Toi Dam 39,320 45,760 60,890 67,250 172,720
Karkh Irrigation Scheme 30,980 36,480 49,340 55,090 74,620 (10k yr)
Kharzan–Hitachi Scheme 89,300 106,300 146,900 164,800 225,400 (10k yr)

2.3 Observed 2024 Floods vs Design Floods

  • Observed Peak (2024): ~58,950 cusecs (Mula Basin).
  • Comparison: Karkh Scheme: observed = 1.6 × 1:100 year flood.
  • Siri Toi Dam: observed ≈ 1:500 yr flood.
  • Kharzan–Hitachi: observed within 1:50–1:100 yr envelope.

This shows the 2024 flood was well within updated design thresholds and validates the conservative hydrological basis.