10-12-2018, 06:51 PM
My guess would be that those were a part of the various early flood alleviation actions done on the Alenaio. This quote is from the 1982 USACE "Alenaio Stream Draft Survey Report and Environmental Impact Statement", from one of many of the engineering reports written from at least 1941 until the eventual Alenaio Stream flood control project in this century:
"Many man-made changes have also been made, most notably the construction of
the waiolama Canal from l9l2-l9l7. Approximately 600,000 cubic yards of material dredged from the beaches of Hilo Bay were utilized in filling the marsh land area along the Waiolama Canal. The waiolama Stream area was used during the pre-contact period for self-sufficient agriculture (taro) and aquaculture (fishponds). Today the Haiolama Stream is a canal that drains water from the Alenaio Stream into the wailoa River.
Various culverts and local drainage systems were also constructed. The most significant project was the Punahawai relief box culvert which originates between Ululani and Kinoole Streets and diverts part of the water flow directly into Hilo Bay through a diversion culvert running east of Punahawai Street. This system was constructed in l924 by local businessmen to help alleviate flooding in the Punahawai area. Over-flows are carried by a diversion weir into the waiolama Canal."
There is this link you may be able to find some research:
http://dlnreng.hawaii.gov/nfip/wp-conten...292017.pdf
"Many man-made changes have also been made, most notably the construction of
the waiolama Canal from l9l2-l9l7. Approximately 600,000 cubic yards of material dredged from the beaches of Hilo Bay were utilized in filling the marsh land area along the Waiolama Canal. The waiolama Stream area was used during the pre-contact period for self-sufficient agriculture (taro) and aquaculture (fishponds). Today the Haiolama Stream is a canal that drains water from the Alenaio Stream into the wailoa River.
Various culverts and local drainage systems were also constructed. The most significant project was the Punahawai relief box culvert which originates between Ululani and Kinoole Streets and diverts part of the water flow directly into Hilo Bay through a diversion culvert running east of Punahawai Street. This system was constructed in l924 by local businessmen to help alleviate flooding in the Punahawai area. Over-flows are carried by a diversion weir into the waiolama Canal."
There is this link you may be able to find some research:
http://dlnreng.hawaii.gov/nfip/wp-conten...292017.pdf