Safeguarding High-Risk Mountain Valleys
Namakab District is characterized by steep, deforested mountain slopes draining into seasonal river channels. In early spring, rapid snowmelt combined with torrential rain generates heavy flash torrents that historically eroded agricultural riverbanks, destroying irrigated wheat fields and inundating residential mud-brick compounds.
Under partnership with Concern Worldwide, ODSAD’s civil engineering unit designed and constructed a 450-meter heavy stone-masonry flood protection retaining wall with stepped stone foundations anchored directly into natural bedrock.
Technical Construction Specifications:
- ✓ Foundation: 1.5m depth excavated to solid gravel bed with stepped mass concrete foundation slab.
- ✓ Wall Structure: Dressed quarry stone bonded with 1:4 cement-sand hydraulic mortar with 1:6 front batter.
- ✓ Drainage System: PVC weep holes installed at 2m intervals along two staggered tiers with backfilled graded gravel filter.
- ✓ Scour Apron: Heavy-gauge galvanized wire gabion mattresses placed at river toe to prevent sub-surface erosion.
"For thirty years, we watched our wheat fields wash away every spring flood. Since ODSAD and Concern Worldwide built this stone wall, our children sleep peacefully during heavy rains, and our harvest is secure."
