ML&P ditch system improvements designed to keep water in Honokōhau Stream during low flow

Maui Land & Pineapple Company, Inc. announced that installation of a remotely monitored and operated diversion in Honokōhau Stream is expected to be completed this week. This improvement to the Honokōhau Ditch System is designed to keep water in Honokōhau Stream during periods of low flow, as currently experienced during the ongoing drought.

West Maui is experiencing historic drought conditions, with only 46% of normal rainfall in the area, resulting in some of the lowest flows on record for Honokōhau Stream, according to the state Commission on Water Resource Management.

New Automated Gates and Communication Infrastructure

In past years, the system’s proposed design focused on diverting water from the stream and then returning water at a later point if streamflow was below minimum required by CWRM’s Interim Instream Flow Standards.

Based on community feedback and in coordination with the Commission on Water Resource Management, an improved system was designed, featuring new automated gates and remote communication technology that will enable operators to control water diversions in real-time based on rain data and stream flows.

“This historic drought has highlighted the importance of innovative solutions that modernize water infrastructure, make it more resilient and better able to safeguard water for public trust uses in all conditions,” Maui Land & Pineapple Company, Inc. said in a news release. “We hope that this solution, which has been developed through collaboration and field testing, will exceed prior design standards by keeping more water in the streams during drought conditions and enabling better oversight through real-time data.”

The new system allows for water to be retained in the stream until it exceeds minimum interim instream flow standards and includes a backup return gate along the ditch to return water to the stream if needed.

Upgrades to Honokōhau Ditch were made possible by technical advancements in satellite communications technology and automation, paired with input from community members and CWRM about the importance of preserving water in the stream.

Construction is planned to continue through Friday, weather permitting, with additional system testing and calibration expected to take place next week.

During construction, Honōkohau Valley residents may see low-flying helicopters transporting materials to the remote area where it is being installed. MLP will continue to update community members on construction activities and share more details after work is completed.

New Data to Drive Smarter Water Resource Management

The new infrastructure incorporates sensors and wireless communications equipment that provide real-time visibility into stream and ditch conditions. These upgrades are aimed at enhancing data-driven decisions about water management.

“We will continue to collaborate with the community, the Commission on Water Resource Management and Hawaiʻi Water Service in making upgrades to obtain more real-time data to inform water management and provide new safeguards to protect public trust uses by preventing diversion during periods of low flow,” Maui Land & Pineapple Company, Inc. reports.

New Data Sets to Promote Greater Transparency in West Maui Drought and Water Use

In an effort to support transparency and community awareness, MLP is developing a web-based dashboard that will make drought conditions, streamflow readings, and Kapalua water usage data publicly available. This dashboard will complement Hawaiʻi Water Services’ existing communication methods.

MLP’s goal is to “foster open collaboration with all interested parties—using accurate, transparent data—to responsibly manage the water resources under the company’s care and deepen understanding of how drought affects water availability and promote conservation and compliance with necessary restrictions.”