INDEX - ENVIRONMENT

www.islandbreath.org ID# 0705-28


SUBJECT: HANAPEPE LEVEE DAMAGE

SOURCE: JUAN WILSON juanwilson@mac.com

POSTED: 5 DECEMBER 2007 -  9:30am HST

Hanapepe levee damaged by rain

image above: Rain on 28 November 2007 washes red mud from west bank levee into Hanapepe River.
Photo by Juan Wilson 11/28/07.

by Juan Wilson on 5 December 2007 Revision 2.3 071206

It began with an unannounced stripping of all vegetation from the east and west bank levees along the Hanapepe
River in March of 2007. This was one year after the Kaloko Dam breach catastrophe. The dam failure highlighted the failure of the state and county government to monitor our reservoirs, dams, levees, and other critical infrastructure.

The US Army Corps of Engineers stepped in and demanded that a survey of all dams and levees be done in the state of Hawaii. Here on Kauai this resulted in a determination that the two most dangerous levees in the state were the Hanapepe and Waimea River structures.

The county of Kauai was instructed to strip the vegetation for inspections and repairs. Heavy equipment was paid for. Lots of labor with chemical spraying, weed pulling and tree root extraction was done. The levees were bare and ugly, kind of like a shaved cat. Unfortunately, the vegetation that was removed so that the Armty Corps of Engineers could get a better look at the levees was protecting them. The roots and mass of plants held the soil in place and reinforced the embankments.

The area involved is about .8 miles long and 50 feet on either side of the west bank levee, and about .4 miles long and 50 feet inside the east bank levee. This amounts to about one-half-a-million square feet of raw dirt embankment.

Once the levees were denuded, measurements were made of erosion and some fill was brought in to "restore" the levee's specified profiles. By summer a couple of new gates were installed to keep public vehicles off the newly tweaked levees.

Here in Hanapepe Valley we began to worry about the replanting of the levee embankments, not only because of the hideous state that the county had left our river valley, but for our protection as well.

On September 4th Gary Uetunten, of thye State Health Department, spoke to Ryan Nishikawa of the County Engineering Department, the man charged with the levee restoration project. Mr. Nishikawa said the County was negotiating with the Army Corp of Engineers on whether an irrigation system can be installed on the levee and if so what kind of system. If an irrigation system can be installed the County would like to plant an approved ground cover on the levee. They are also considering applying a compound to help keep the dust down as a temporary measure.

Linda Harmon, who lives inside the west bank levee wrote to neighbors:

"The levee is bare of vegetation and has been for months. My fear is nothing will be planted in time and there will be mass mud slides into the river causing a die off of river flora and fauna, not to mention covering any coral reef beyond the river mouth that might be trying to make a comeback. What is to keep the eroded levee from washing away?"

Towards the end of September neither the irrigation system or any dust mitigation had been achieved. In fact nothing but some touchup work with the herbicide seems to have been done.

The people in the valley composed a letter to the Mayor of Kauai, our County Council, the Engineering Department, and to the Hawaii  State Department of Commerce and Consumer Affairs. That letter stated that that the "Hanapepe levee was in peril of winter rains", it ended with...

"The very improvements the County has tried to implement may be washed aside during a storm, allowing flood waters to descend on us due to the county letting the ball drop on replanting the levee. Certainly, if there is damage to property or the environment the County will have exposure that could easily have been avoided."

Since November, the county Engineer, Donald Fujimoto, stated that despite project engineer Nishikawa's statement, that his department had no budget for replanting the levee. He was considering spraying a polymer coating on the levee for its protection through the winter and until planting could be done in 2008.

This only added to the alarm of valley residents concerned with the possible toxic effects of an an application of a polymer coating and its subsequent breakdown and runoff. Those residents told Donald Fujimoto that there was still time to act and that the "Hanapepe levee still needs stabilization". Nothing happened.

Then on November 28th 2007 something happened. The first heavy rain came to the newly "restored" levees on both sides of the Hanapepe River and they were damaged. The rainstorm was only for a day. Nothing compared to the forty days of rain that inundated many parts of the island in march 2006, but there was dramatic erosion that will need repair.


image above: rainwater carries earth from the east bank levee of the Hanapepe River through the yards to storm water drains along Hanapepe Road and out to the ocean. Photo by Juan Wilson 11/28/07.

Look at the pictures to appreciate the damage done to the levee with this one seasonal deluge. And don’t forget this is just the beginning. We did have rain for 40 days in March of 2006. This late November rain is likely just a just a precursor to what is likely this winter.

 


image above: New fissures and gullies on levee wall created by a day of rain illustrate how fragile levees are now compared the spring of 2006 when they weathered historic rains. Photo by Juan Wilson 11/28/07.

Along both sides of the river the levee erosion filled residential backyards with muddy water that made its way to the street. Quite a bit of cleanup was required afterward. In some places erosion gullies were 12" to 16" deep. It appears that little or no compaction of new levee material was made while the "restored" profiles were being achieved. The damaged embankments also reveal that fill brought in contained some rubble, garbage and organic material. This is not proper fill for a structural renovation like a levee.


image above: Note the sticks and foreign material exposed by erosion on levee wall after 11/28/07 rainstorm.
Photo by Juan Wilson 11/28/07.

The safety to residents whose back yards abut the levee during the spraying of polymer on the levee has not been demonstrated. The county Engineering Department is inexperienced with the technology. When asked in a phone conversation whether chemical masks were required during application the County Engineer was not sure.

Some residents who are concerned with the health risks have asked for prior notice of any spraying. The spraying could take several days to complete, with clouds of polymer vapor in the air. In addition, residents have asked that if chemical masks are required on workers during application of the polymer, that a temporary evacuation should be considered for all residents and domestic animals who might be endangered.

The county has failed the Hanapepe community. It should treat the current situation as the emergency it is: an environmental crisis. We don't have to wonder if there will be environmental damage because of the County's inattention to this matter. The damage to the environment has already begun.


image above: The footing of the new gate post at the south entrance to the west Hanapepe levee (at Awawa Road) was undermined in the first rain of the season. Note plastic bag (lower right), stick and other organic material exposed in fill. Photo by Juan Wilson 11/28/07.

The mayor and county council should release funds for doing the job they should have done last summer. Now it will cost more, be less effective and there will be remedial work due to the erosion that has already occurred.

It should be noted that nature is beginning to make a comeback on the levee embankments without the help of the county. It may not be the county's preferred species, but it's what mother nature can do on her own as quickly as she can.

That does not mean the job should be ignored.

The county could spray on a quick germinating seed like rye grass mixed with bermuda and loaded with some fertilizer or urea to reinforce the new groundcover that is now developing .

If the county continues to claim they have no budget to do anything, the next step by the community could be to call in the EPA with a complaints about the Clean Water Act being violated and point to the county's liability on this issue.


image above: bend two-thirds up west levee on Hanapepe River from Eleele School grounds show mud running off levee and polluting river. Note that some plants are beginning to get re-established (lower left) after herbicide spraying in spring. Photo by Juan Wilson 12/3/07.

This matter raises several questions and provides some answers too. Obviously, the county had no rational plan to handle this project to its completion. They entered into it without an adequate budget, leaving our environment and our health at risk.

How could that happen? Why doesn't the county see this as an emergency? Do they only respond to pressure by hiring expensive consulting lawyers when faced with their own incompetence and shortcomings?

The Army Corps of Engineers has shown no responsibility to really protect our levees so that they can protect us and our environment. They mandated the state and county to act, but have not seen the project through with expertise, management or resources. No wonder we lost New Orleans. Our levees were better off without their "help".

see also:
Island Breath: Hanapepe Levees 2 11/7/07
Island Breath: Hanapepe Levees 09/23/07

Island Breath: Hanapepe & Waimea Levees Faulty 4/21/07


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