Flooding Forecasts, Climate Research Among Casualties of Stream Gage Losses

posted in: November 2011, Water | 0

The cost to operate a stream gage is roughly $22,500 a year. The potential cost, in lives and property, of not operating it is incalculable.

So, when the U.S. Geological Survey announced recently that it would be ceasing operations of 22 gages – 10 of them on streams on O`ahu, Moloka`i, Maui, and Hawai`i island – Mike Cantin, the warning coordination meteorologist with the National Weather Service in Honolulu, was alarmed.

Shutting down the gages “will have an impact,” he told Environment Hawai`i. “These gages are part of a network we used in our warning process. The fewer data points we have, the less hard ground-truth data we have to aid in our forecast process.”

Rain gages, some operated by the Weather Service, some by other agencies (including the USGS), are no substitute, Cantin said. “They help you when the rain is falling directly over a stream or stream basin, but if the gage isn’t there, you won’t get the true measure.” Stream gages, he said, are the best way “to see how rain is translating down the stream basin.”

The loss is also felt by scientists and researchers as well. Since 1947, a U.S. Geological Survey gage on Waikoloa Stream, near the Big Island town of Waimea, recorded stream flows, giving scientists a 65-year-long record of hydrologic conditions. It’s just the kind of data set that is coveted by scientists looking into long-term weather patterns and climate change.

No more. The Waikoloa gage was the longest-running of the discontinued sites, but not by much. Gages on Kipapa Stream and the south fork of Kaukonahua Stream, both near Wahiawa, had been in operation since 1957. 

Two other gages, both on O`ahu’s North Halawa Stream, were on the USGS hit list, but were reprieved by the state Department of Transportation. It is required to monitor those streams as a condition of building the H-3 highway.

Ron Rickman, the data section chief at the USGS Pacific Islands Water Science Center in Honolulu, says the cost of operating a stream gage such as that near Waimea is $22,500 a year, while a co-located rain gage cost $9,000 a year. (A stand-alone rain gage is $10,800 a year to operate.) 

The state Commission on Water Resource Management is the largest cost-sharing partner with USGS in the Hawai`i monitoring effort, with a contribution this year of just under half a million dollars to help run 59 USGS gages and observation wells. Its contribution covers around 57 percent of the total cost of the program, which, in the current federal fiscal year, comes to almost $900,000.

Other agencies help out. In addition to the DOT, state Civil Defense has assisted in paying for several other gages, Rickman added, noting that the recently resigned deputy Civil Defense chief, Ed Teixiera, had been “a really big advocate” for gages.

When it became apparent earlier this year that the USGS gaging program would be taking a serious hit, “the National Weather Service really went to bat for us,” Rickman said. “They sent letters to the governor, to congressional staff.” Everyone has been made aware of the problem, he said, but with tight budgets all over, “their hands are tied.”

John Cummings, public information officer of the City and County of Honolulu’s Department of Emergency Management, acknowledged that the agency was aware of the discontinuation of gages at Kaukonahua and Kipapa streams, as well as rainfall monitoring at Manoa Stream.

“We are understandably concerned that these systems were the unfortunate victims of federal budget cuts,” Cummings wrote in an email to Environment Hawai`i. “Elimination of these gages statewide could affect the timeliness and accuracy of weather forecasts.”

Still, he said, the losses “should not radically impact our ability to alert, warn or evacuate residents when severe weather produces a significant amount of rainfall.” Kaukonahua Stream still has one monitoring station functioning, while Kipapa and Manoa streams “will be supported by direct field observation reports” from city employees and citizen volunteers, he wrote.

A Long Decline

Cooperative monitoring of streams and groundwater in Hawai`i began more than a century ago, when, in 1909, the USGS and the Hawai`i territorial government placed the first gages on 12 streams, according to a report prepared earlier this year for the state Commission on Water Resource Management. From that point up to 1966, the number of gages rose steadily, reaching a peak of 197 gages measuring rainfall and streamflow. 

In 1972, groundwater monitoring wells were added to the program, with 170 such wells eventually established. Now only 18 remain in use. According to CWRM’s Report to the 2009 Legislature, “beginning in 1998, the Commission streamlined the cooperative agreement by transferring the crest-stage stream-gaging program to civil defense agencies where these data (e.g., flooding issues) are more relevant to disaster response rather than sustainability issues, and by eliminating duplication of groundwater data collection efforts in wells.” Data on groundwater would henceforth be provided by water system purveyors and well owners, “who were required by law and rule to report their water-use and groundwater and chloride levels.”

But well owners and operators have a poor record when it comes to self-reporting. According to CWRM’s Roy Hardy, the commission receives regular reports on just a fraction of the known production wells. And even when reports are received, the commission has no staff to analyze it. “We lost our survey branch people, who were keeping track of this before,” Hardy said.

In recent years, the Department of Land and Natural Resources’ Land Division, Engineering Division, Division of Forestry and Wildlife, and Division of Aquatic Resources had helped out with the costs of gaging, motivated by a variety of reasons.

In the Land Division’s case, said Rickman, stream monitoring in East Maui had been undertaken as part of the dispute over rights to stream flows.

The Division of Forestry and Wildlife used part of its Watershed Management Grant Program (WMGP) to gage streams on lands in watershed partnerships over several years in annual amounts ranging from a high of $132,000 (fiscal 2007, when 16 gages were operated) to a low of $49,000 (fiscal 2009, when it ran four gages). But, according to a staff report to CWRM for its July meeting, when the commission authorized renewal of the joint agreement, “the WMGP has withdrawn its support … disengaging the watershed partnerships from Commission and USGS efforts in monitoring the water resources in watershed areas.” 

The Waiahole Trust Fund, established as part of the resolution of the long contested case over windward streams, helps defray the cost of monitoring Kahana, Waiahole, and Waikane streams. The amounts vary – from a high of $50,500 in fiscal 2010, to a low of $32,850 for the current fiscal year.

Vital Information

The most recent cuts are only the most drastic in the four-decade-long decline of the joint water resource monitoring program. Just seven years ago, there were 39 stream gages statewide, 71 monitoring wells measuring water levels and water quality, and 25 rain gages. Today, the numbers have dropped to 27, 18, and 14, respectively – declines of 30 percent, 75 percent, and 44 percent.

In its report to the 2011 Legislature, the Water Commission commented on the loss of this monitoring capacity. “Over 140 (37 percent) of the 376 perennial streams in Hawai`i have been gaged since the inception of the cooperative program,” the report stated. “However, the steady decline of the number of monitored streams has diminished the ability of water resource managers to understand and appropriately manage the state’s surface waters….

“Long-term stream data is vital for flood analysis in the construction of roads and housing developments, assessment of water quality criteria and dam s
afety, and the long-term monitoring of streamflow trends, erosion, and other environmental concerns.”

Lenore Ohye, a planner with the Water Commission, stressed just how serious the loss of data is. “We’re really concerned that we’re losing baseline data, and with us now on the cusp of climate change, it is even more critical to know what’s going on hydrologically. Along with the USGS, we’re trying to spread the word about the importance of data collection, but our own budget keeps getting cut, too.”

Ohye noted that in the past, data collection was not the job of the state and USGS alone. “When the plantations were in operation, they had their own rainfall stations,” she said. “It informed a basic business decision – to irrigate or not. They had a lot of good records, of evaporation as well as rainfall. And all those stations are gone now, too.

“It’s quite alarming when you think about it, and everybody’s scrambling. To me, personally, basic data collection is critical. Every day that goes by when you don’t have that data point, you can’t get it back. I recently went to a conference of western state water planners. USGS people were there, other federal agencies. One common theme across all states was the USGS needs to be better funded. All of us need more data.”

According to Hardy, the CWRM staff is discussing how to augment its support for the gaging program and rebuilding its capacity to analyze data.

Patricia Tummons

Volume 22, Number 5 — November 2011

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