Locks on the river could prevent flooding
The flow of the Chao Phraya River is in the news now, and one of the problems with the flow of the river is, of course, that it flows south and then "loops" north again to the port at Klong Toei, in effect stopping in its tracks before it regains momentum
The loop itself closes at points that are less than one kilometre apart, north to south, and a canal or water tunnel connecting those two parts of the river would speed the flow of the river into the sea.
The northern of those two points is at a narrow part of the river, and that would be a good place for locks, the types used in the Panama Canal to lift ships almost 26 metres high. They could be used in the Chao Phraya River to keep the river levels low while the sea levels to the south are higher.
I have been looking into this for more a year now.
The Pacific Ocean at the Panama Canal is about 20 centimetres higher than the Atlantic on average, but tidal variations on the Pacific side are much greater than on the Atlantic side – six metres versus 30 centimetres – and “locks” help make up the difference.
A set of locks on the Chao Phraya River could keep the sea from “backfilling” the river in the dry season and thus provide more space for floodwaters in the rainy season. Simply put, the locks would stay closed when the river level is lower than sea level and would open when the river level is higher than sea level, thus forbidding the sea to go any further north than the locks.
Only engineers with all the data, however, would know if the locks would keep the Chao Phraya at low enough levels to justify their cost.
Guy Baker
Bangkok
