Bisokotuwa (reservoir valve pit)
Bisokotuwa (pozo de compuerta de embalse)
- Date
- c. century I a.C. · confidence low
- Place
- Anuradhapura, North Central Province, Sri Lanka
- Credited to
- Sinhalese engineers
- Field
- Tools
⚠️ Disputed: the sources disagree.
What it is
Stone or brick chamber at the base of the dam that allows water to be released from the reservoir at controlled pressure without eroding the embankment. It functions as a valve tower and allowed much higher dams to be built.
The dates of the earliest bisokotuwa vary between the 3rd century BCE and the 3rd century CE according to different authors.
What it led to
- large-capacity reservoirs with regulated outflow
- reliable year-round irrigation