Wadi Hanifah Dams (Diriyah Dam System)
سدود وادي حنيفة · Hanifah Dams · Diriyah Wadi Dams
Najdi Emirate to First Saudi State·Najdi oasis (Diriyah Amirship)·🇸🇦 Riyadh Region, Wadi Hanifah, Diriyah to Riyadh, Saudi Arabia
About
About Wadi Hanifah Dams (Diriyah Dam System)
Wadi-bed dam cascade in Wadi Hanifah (620 m) 8 km northwest of Riyadh at UNESCO At-Turaif Diriyah world heritage, 120-km wadi incised 40 m deep in Najd limestone. Historic system 15th–18th c. Najdi oasis agriculture: 6 gravity dams 3–6 m high, 40–120 m long of coursed limestone with earth-core, stepped spillways, and upstream silt-trap basins feeding palm grove qanats and Bir spring. Largest Diriyah Dam 6 m × 120 m traps 45,000 m³; spillway carved into limestone bench. Restored under Wadi Hanifah Environmental Restoration 2005–2010, now wetland bioremediation chain. Dams irrigated Diriyah capital of First Saudi State.
Why it mattersOnly Najdi wadi-dam oasis cascade integrated with Diriyah First Saudi State capital UNESCO site.
Open questions
Mysteries & theories
Mysteries
- 01How silt traps maintained palm water without salinization
Theories
- 01Qanat recharge via dam silt
Theories are interpretations, not findings. The seal above tells you how much scholarly weight the place carries.
History
How it came to be
- Built
- c.1450 – 1750 CE
- Period
- Najdi Emirate to First Saudi State
- Culture
- Najdi oasis (Diriyah Amirship)
- Builders
- Diriyah Najdi oasis builders under Al Saud forebears
- Purpose
- Wadi flood harvesting, silt-trap, and palm-grove qanat recharge at Diriyah capital oasis
- Abandoned
- 1950s (modern pumps but dams preserved as heritage wetlands)
- Rediscovered
- 2005 Wadi Hanifah Restoration survey; UNESCO 2010 At-Turaif inscription 1729
- Excavation
- Partially excavated
1450 CE
Earliest palm-grove wadi dams at Diriyah
2010 CE
UNESCO At-Turaif Diriyah inscribed 1729; Hanifah wetland restoration
On the ground
Structures & features
24.7300° N · 46.5700° E · 620 m · 2 mapped features
Diriyah Main Dam 120 m
dam6-m high 120-m long gravity dam with 45,000 m³ basin at At-Turaif
24.7320° N · 46.5680° EWadi Hanifah Silt-Trap Basins
reservoirUpstream silt basins feeding palm-grove qanats, 40 m deep wadi
24.7280° N · 46.5720° E