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Conservation Releases, Schoharie Reservoir

Written by; Howard R. Bartholomew

Thirty-five miles north of its origin at Acra, Greene Co., NY at an elevation of 2,500’ the Schoharie Creek ceases, for some considerable distance, being a perennial stream. Perennial, or “year round” steams occur where ground water and surface water systems are naturally and hydraulically connected. As a result of the 2000’ long, 182’ high Gilboa Dam, the Schoharie Creek below the dam is transformed into an intermittent stream. Even in times of drought, perennial streams keep flowing at an albeit reduced rate. This is because ground water continues to supply water to these creeks, river, etc. in spite of a lack of surface water or run-off. Unlike perennial streams, intermittent streams stop running during dry weather. Intermittent streams are normally found in arid regions such as the American South West. They are sometimes referred to as dry gulches.

(1) Some ravines in the Catskills, which were once conduits for melt water from the glaciers at the end of the Pleistocene, are seasonal or intermittent in their flow. One does not normally expect to see a stream in a wet region like the Catskills become intermittent. So effective is the Gilboa Dam, its grout curtain and cutoff trench in halting down stream flow of the Schoharie Creek, below the dam, that the creek literally “dries up” for a distance of .8 miles until the creek is revived by a minimal discharge from the Platter Kill, USGS #01350120. As this tiny stream has a catchment of only 10.9 sq. miles, its contribution to the Schoharie Creek is negligible. A table showing Platter Kill flow for a 33 year period can be found in the appendix. The annual phenomenon of the Schoharie Creek going dry below the Gilboa Dam generally occurs during the summer months of June-September. USGS surface water annual statistics for site #01350000, Prattsville, NY and site #01350101. Gilboa, NY can be found in the appendix and the figures speak for themselves. It can best be summed up by the USGS itself in describing the situation at Gilboa as “entire flow, run off from the 315 sq. mile, except for periods of spill, diverted from Schoharie Reservoir through Shandaken Tunnel into Esopus Creek upstream from Ashokan Reservoir for water supply of City of New York”. An equally dramatic example of the impact of the diversion of Schoharie water to Ashokan Reservoir is in the chart “Burtonsville vs. Prattsville”. Burtonsville is 41 miles, by creek, North of Prattsville. Burtonsville, USGS # 01351500 has a catchment area of 649 sq. miles below the Gilboa Dam, as compared to the 237 sq. mile drainage basin at Prattsville. It is were not for the substantial ground water resources of the Schoharie Valley, the Schoharie Creek at Middleburgh would be nearly as low as it is below the Gilboa Dam during the dry summer months.

(2) Tributary flow is not measured below the Mine Kill, USGS #01350140 which enters the Blenheim-Gilboa Power Project Reservoir and USGS maintains three more gauge stations below the PASNY Pumped Storage Reservoir, Blenheim, NY, USGS #01350180, Breakabeen, NY, USGS #01350355, and Burtonsville, NY. Contained in the appendix are several stream flow data sheets showing there to be more water at Prattsville than at Burtonsville! This is not an anomaly; it happens every year.

We will now briefly turn our attention to the tributaries below the Gilboa Dam that enter the Schoharie Creek. As the Schoharie Creek channel is of pre-glacial or perhaps inter-glacial origin, it has many “hanging valleys”, where smaller alpine glaciers met the larger ice sheet that advanced and retreated only to re-advance several times during the Pleistocene Epoch.

(3) These hanging valleys are characterized with having one or more water falls. All these tributaries of the Schoharie Creek in Schoharie County contain Char, Brook Trout (Salvalinus fontinalis), Brown Trout (Salmo trutta), and Rainbow Trout (Salmo gardneri). The latter two species are introductions in the Schoharie. All three species move seasonally between the main stem river, or “Big Creek” as it is referred to locally, to the mouths of the “tribs” seeking thermal refuge in the warmer months. Deep, scoured “spring holes” abound in the Schoharie, proper, and are fed by ground water. Two major tributaries of the Schoharie flow over and originate in limestone. They are Foxes Creek, which enters North of the Village of Schoharie from the east and the Cobleskill (creek) which enters the main river from the west, and has a little known water falls formed of Schenectady Bed Sandstone. Near by is the out fall of spring water from “Jack Patrick’s Cave” and the “Cow Sink”. Foxes creek has numerous springs and cave water sources. An excerpt from Jeptha Simms, “The History of Schoharie County and Border Wars”, published in 1846 gives an account of the fish present in the region when it was first settled by Europeans in the early 18th century. On pages 86-87 Simms states, “Fish are said to have been very plentiful formerly in most of the streams in Schoharie county. For many years after the Revolution, trout were numerous in Foxes Creek, where now there are few, if any at all. From a combination of causes, fish are now becoming scarce throughout the county. In many small streams, they have been nearly or quite exterminated by throwing in lime. This cruel system of taking the larger, destroys with more certainty all the smaller fish. Such a mode of fishing cannot be too severely censured. The accumulation of dams on the larger streams, proves unfavorable to their multiplication. Fine pike are now occasionally caught in the Schoharie, as are also suckers and eels. Some eighty years ago, a mess of fish could have been taken, in any millstream in the county, in a few minutes.” Conditions have improved considerably since this was written more than 150 years ago.

Another reference to the presence of Brook Trout in the main stream of the Schoharie can be found in “The Ultimate Fishing Book”, edited by Lee Eisenberg and DeCourtney Taylor, Houghton Mifflin, Co., Boston 1981, p. 56. In a chapter entitled “Opening Days”, by the late Ernest Schwiebert we read, “The Schoharie is still a native brook-trout fishery in its headwaters on the timbered summits of Indianhead. Its gathering currents riffle over ledges there, through vast thickets of rhododendron and the overgrown walls of abandoned colonial farms and it tumbles through huge boulders in other places. The swift runs and pools above Hunter are classic Catskill water, and in the valley at Lexington, it becomes a series of sweeping riffles and smooth flats. There are deep ledge rock pools downstream, and before the Gilboa Reservoir (sic) warmed its lower mileages, the old-timers told us, there had been excellent trout fishing as far downstream as the covered bridge at Blenheim”.

The picture taken of two Brook Trout, caught simultaneously on a “3 fly” cast on May 28, 2008 bears out this statement by Schwiebert. These fish were caught 1 mile downstream of the Covered Bridge at North Blenheim at the mouth of a cold water spring, in a 14’ deep, scoured hole in the main stem of the Schoharie. It was not a “fluke” or a one time occurrence. All three species previously mentioned are found below the Gilboa Dam in spring holes. A map showing, by name, the tributaries of the Schoharie Creek within Schoharie County, along with a Karst map of a portion of the Schoharie Valley is found in the appendix. The impact of the Gilboa Dam on the fishery of the Schoharie Creek has been great over the last 82 years, but it has not been devastating. Walleyes or Pike Perch (Sander vitreus) referred to by Simms a “pike” can be found in the big pools or eddies of the Schoharie. However, the supply of invertebrates such as fly larvae, hellgrammites and crayfish that juvenile Walleye eat is negatively impacted by low surface flow through riffle areas that connect the big pools of the Schoharie Creek below Gilboa. The elevation of the Schoharie at the base of the Gilboa Dam is c. 939.56’. It is 507.98’ at Burtonsville. As there are about 40 miles of stream between these two gauge stations, the average rate of fall per mile is 10.7895’ per mile. There are three greatly eroded ledge rock falls on the Schoharie between Gilboa and Burtonsville, one above the Covered Bridge, North Blenheim at Frisbieville and one a short distance upstream from the gauge at Burtonsville. There is a ledge of Onondaga limestone just north of Middleburgh. As none of these falls are very high, the rate of drop per mile is pretty uniform. It is in the area of drop between pools that the riffle areas occur. It is these very riffle areas that suffer most when the Gilboa Dam stops spilling, as surface water diminishes so greatly in volume. The annual rainfall for Schoharie Co. is 38.1”, according to the Progressive Farmer website of 2008. The average rainfall for the Schoharie Watershed above the Gilboa Dam is 41”; Schoharie Creek Management Plan, www.gcswcd.com/stream/schoharie.eastkill/schohariecreeksmp. It is the deprivation of this extra 3” inches of rainfall that is so detrimental to riffle flow between pools on the lower reaches of the Schoharie Creek. A fair question is, Where would the water “come from” to create a base level flow of 50-75 cfs at Gilboa, in times of non-spillage of the dam?. The rainfall chart found in the appendix shows annual average precipitation, actual precipitation and a “trend line” for the Schoharie Creek Region. Also, included are annual weather summaries for the years 2006-2008. This graph’s trend line is supported by the newspaper clippings. More rainfall is falling in the watershed in 2009 than there was at the time the Gilboa Dam was built. Accompanying the over 14% increase in rainfall in the watershed is the fact that NYCDEP, operators of the Gilboa Dam and Schoharie Reservoir are limited to allowing no more than a combined flow of 300 million gallons per day (mgd) of the Esopus Creek during the months of June-October. This seriously impacts the output of the Shandakan Tunnel in the summer months when water is so desperately need north of the Gilboa Dam. Using information provided by USGS on monthly water statistics for the Esopus Creek at Allaben, NY site #01362200, we find that the discharge for the creek was an average of 118, 59, 39, and 60 cfs for the months of June-September. To convert cfs to mgd, multiply cfs by 86,400 (# of seconds in a day) and multiply the result by 7.481 (the # of gallons in a cubic foot of water). The converted mean stream flow for a return period from 1963-2007 for the months of June-Sept. is as follows: June-76,270,291 mgd, July-38,135,145 mgd, August-25,207,977 mgd and Sept.-38,781,504 mgd. Subtracting these figures from the 300 mgd limit imposed by the “SPDES” Permit, we arrive @223,729,709.0 mgd tunnel limit or 374.74 cfs for an average June. As 300,000,000 mgd is the equivalent of 464.13 cfs over 24 hours, we find that the July, Aug. and Sept. figures for the Shandaken tunnel discharges are as follows: July-405.13 cfs, Aug.-425.13 cfs, and Sept.-404.13 cfs. As the carrying capacity of the Shandaken Tunnel is over 900 cfs at its present state,(4) we see that large quantities of water are left in the Schoharie Reservoir during times of SPDES compliance by NYCDEP. The installation of an Obermeyer Gate system in he 220’x5.5’ deep notch in the spillway portion of the Gilboa Dam will allow a full pool level of 1130’ to be achieved as it was during the years from 1972-2005, prior to the emergency declaration at Gilboa. Obviously some of the “extra water” could be and should be used for Conservation Releases from the Schoharie Reservoir. This is factually demonstrated from the following figures based on actual monthly discharges and their mean monthly quantities over a given number of years. Some of the measurements are based on records collected for over century, such as the records kept on Schoharie flow at Prattsville. Other are of a shorter duration, such as Toad Hollow. All relevant tables are found in the appendix.

Water input Schoharie Reservoir from USGS Monitored Sources based on mean of monthly discharges expressed in cfs

Water diverted from Schoharie Reservoir since SPDES Compliance by NYCDEP expressed in cfs

Based on the latest discharge figures since the SPDES constraints have been in effect, we see that the month of June had a 198.40 cfs “surplus” over “output” from the Schoharie Reservoir; the month of July had an output of 35.70 greater than combined reservoir input; Aug. was a negative figure also @ 37.74 cfs, Sept. was positive 44.7 cfs over output. Taken all together, we find that for the periods mentioned, which are four driest months, there were 42.42 cfs more water going into the Schoharie Reservoir than were being sent to the Ashokan Reservoir via the shandaken Tunnel.

At present, full pool elevation in the Schoharie Reservoir is 1124.5’ due to the 220’x5.5’ ungated spillway notch. This makes for a capacity of about 18 billion gallons. Once the Obermeyer Gate system is installed, scheduled for fall of 2009, full pool level will be restored to 1130’, with a capacity of 19.583 bil. gal. These extra 1.5 bil. gal more than insure the ability of the Schoharie Reservoir to meet its water supply requirements to the Ashokan Reservoir, while providing conservation releases to the Schoharie Creek, north of the Gilboa Dam. Mark Twain is quoted as saying that there are 3 forms of falsehood...in order of magnitude; a lie, a damn lie, and a statistic. A lot of figures have been presented in this paper. They are all found in the appendix and those who read this paper are invited to draw their own independent conclusions on the veracity of DCC, Inc.’s position that sufficient water exists for conservation releases, without impairing in any way the quantity or quality of water discharged through the Shandaken Tunnel. DCC, Inc. is not asking for the coldest portion of the water column in the Schoharie Reservoir. The fishery of the Esopus Creek has come to depend upon that water. Rather, the Schoharie Creek needs flow to connect the spring fed eddies. Furthermore, reasonable people would consent to a temporary cessation of conservation releases, during times of drought or other emergency of any kind, if they were “ramped down” in an orderly manner over a period of 12-24 hours. Pictures below show results of the abrupt stopping of dam spillage that occurs when the Shandaken Tunnel discharge is suddenly increased to full capacity.

Thus far, we have dealt with matter pertaining to geology, the environment, hydrology and engineering. We will now turn our attention to a very troubling legal issue. This issue is the agreement reached in the settlement of a case brought by the City of New York against the NYS Department of Environmental Conservation, in the Supreme Court of the State of New York, County of Albany, Index #5840/80. It was resolved by a stipulation of discontinuance, which means that NYSDEC Commissioner Robert F. Flacke agreed to terms set out by the City of New York concerning conservation releases from New York City owned reservoirs. In a nutshell, the “City” would drop its case against NYSDEC if the commissioner consented to abide by certain stipulations. The full text of this stipulation of discontinuance can be found in the appendix. The second article of this agreement states that...”New York State will not at anytime require releases from Schoharie, Ashokan or Kensico Reservoirs, except as provided herein”.

For several years people concerned with the Schoharie Creek and the Gilboa Dam have heard vague allusions to some law or agreement that exempted NYCDEP from making conservation releases from the Schoharie Reservoir. This case is the “Baby”. Stipulations rhymes with capitulation and that is what it amounts to. For a Commissioner of the Department of Environmental Conservation to sign such an agreement is beyond belief. This case is to the environment what the Dred Scott decision is to civil rights. It is a wrong that must be righted, a legitimate grievance that must be redressed. The stipulation of discontinuance is 29 years old this October and “a lot of water has gone over the dam” in terms of environmental awareness since 1980. “Tunnel Vision” in reservoir operation is as bad as narrow mindedness in any other endeavor. A reasonable, intelligent exchange of ideas can lead to an equitable sharing of the water resources of the host or donor communities in the Catskills and the recipients of the vital water they require. With the impending reconstruction of the Gilboa Dam, the time is NOW !!!

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Footnotes

1. Water Encyclopedia-Ground Water: Hydrologic Cycle, Patricia S. Irle, internet.

2. Ground Water Resources of Schoharie Co., NY, Jean M. Berdan, p. 28

3. Berdan, p. 27.

4. Susquicentennial Gilboa, NY, 1848-1998, Linda Trautman, Stratigos, ed., p 71.

Bibliography

1. Berdan, Jean M., "The Ground Water Resources of Schoharie Co. NY, Albany, NY Bulletin G W-22.

2. Board of Water Supply City of NY, "Annual Report for 1925".

3. Eisenberg, Lee & DeCourtney, Taylor, eds., "The Ultimate Fishing Book", Houghton- Mifflin, Boston, 1981.

4. Fetter, C.W., "Applied Hydrology", University of Wisconsin, Oshkosh, 1994.

5. Fluhr, T.H. & Terrenzio, V.G., "Engineering Geology of the NYC Water Supply System", NYS Geological Society Bulletin, Oct., 1984.

6. NYCDEP Bureau of Environmental Planning and Analysis, prepared by Hazen Sawyer/Gannet Flemming, a joint venture, "Final Environmental Assessment Gilboa Dam Reconstruction, July 2008.

7. Simms, Jeptha R., "The History of Schoharie County and the Border Wars", Schoharie Co. Council of Senior Citizens, reprint 1974.

8. Stratigos, Linda T., "Susquicentennial Gilboa, NY 1884-1998, Gilboa Historical Society.

9. Titus, Robert, Ph.D., "The Catskills in the Ice Age", Purple Mt. Press, Fleischmanns, NY, 2003.

10. Van Diver, Bradford B., "Road Side Geology of New York, Mountain Press Co., Missoula, Mt., 1985.

Dam Concerned Citizens, Inc. would like to express its gratitude to the United States Geological Survey and their website, "Real-time Data of New York Stream Flow" and their many useful links.