We are not against flood mitigation. We are protesting certain elements of the proposed plan of the Ala Wai Canal Project. We are asking the government to engage the public and carefully assess this project. Federal funds have been granted and we believe the money should be put to proper spending and avoid being unnecessarily detrimental to the land and residents.
Let’s come together as a community
and demand the government reassess the
Alternative: Flood Gate and Flood Pump
We believe the solution is to follow what is done in New Orleans and install a flood gate at the Ala Wai Boulevard Bridge and use high capacity flood pumps. With today’s weather radar we could predict the storm ahead of time and could close the flood gate at the lowest tide in advance of a storm to let nature do some of the draining. Then gate it up and pump out the rest. Rather than built a 4-foot solid reinforced concrete wall to create the capacity, we can lower the elevation in the Ala Wai Canal 4-feet to create the same capacity.
Flood pumps speeds can be adjusted to accommodate any size storm or magnitude. Inlets can be positioned at the intersections of major streams like near the Manoa stream intersect or at the end of the canal. All pumped water can be mechanically screened for trash and debris before being pumped out to the ocean and skimmed for oils. The outlet can be at the Ala Wai Harbor or further out to sea.
If outlets are positioned further out to sea the pumps can be reversed to help circulate the water in the Ala Wai from becoming stagnant. Fresh ocean water can be pumped in from the deep ocean as an option. The power to run the pumps during the day can be produced from solar panels farms out in the Ewa plains.
This would permit our existing gravity storm drainage system to work as designed without the need to mechanically cap all the outlets to the Ala Wai Canal to prevent backflow as would be required with a 4-foot wall.
The USACE plan does not protect large areas on the Mauka side of the Ala Wai Canal and are sacrificed because they cannot accommodate all the water or would have to raise the wall to a height that would be totally unacceptable. This would not necessarily be a problem with the flood gate and flood pump and existing storm drainage systems can work as designed and the flood pumps can handle the additional storm waters.
The flood gate and flood pump method would also be able to protect us from sea level rise. If it becomes true, then the Ala Wai Canal water level can permanently remain below sea level so that our existing gravity stormwater system will still be able to function.
Funding can be spent on shoring up the ocean side to protect from sea level rise and not have to worry about the Ala Wai Canal side.