The spillways on both the Sandusky and Scioto should be constricted retarding spillways, so as to maintain a retarded bankfull flowage both ways, while the upper part of the reservoir is filling with excess flood waters, which can be up to the 900-foot level with a minimum of damage, if certain towns are protected by local levees.

The maintenance of low-water flowage down the two rivers would result in a beneficial drawdown on the flood storage capacity of the summit reservoir, and the usable diluting effects that are so needful in both the Sandusky and Scioto Rivers during drought periods. Droughts have become the common occurrence in recent years, with a water shortage for Columbus.

By using the proposed Columbus water supply reservoir dam site at Bellepoint for the summit diversion dam in the Scioto River at 890 feet mean sea level, then the combined drainage area to be controlled would total about 1,100 square miles in the two watersheds will 30,000 areas of a surface reservoir.

Such a storage and flood retardation of 1,100 square miles of run-off on the summit of the State in a multiple-purpose reservoir will result in the development of many benefits.

Such an accumulation of surplus floodwaters in the Sandusky watershed, that can be released, as needed, down the Sandusky River channel for use by the cities along the way, will completely change the present low-water flowage past those Sandusky Valley cities and towns.

Since 770 square miles of the drainage area of the Scioto River is the greater part of this combined headwater control, then Columbus and the entire lower valley would be guaranteed flood control and a greater water supply and a much needed dilution of a constant low-water flowage, with a regulated drawdown of the summit reservoir through both rivers in preparation for maximum flood control, when most needed.

After the excess flood flowage has passed down both rivers and the waters have receded in the Summit Reservoir to the normal pool level of about 890 feet mean sea level, the outlets could be regulated to release a constant normal flowage down the channels of about 200 cubic feet per second for the Scioto River, 100 cubic feet per second for the Sandusky, and 25 cubic feet per second for the Tymochtee Creek.

This amount of regulated flowage would about drain off the top 5 feet of the conservation pool down to 885 feet mean sea level in 220 days if the inflowing streams did not replenish the reservoir with run-off water from the rainfall during that period of drawdown. But droughts of 220 days duration have never been known in this section of the country.

Columbus waterworks uses about 60 cubic feet per second per day, so that there would be an excess of about 140 cubic feet per second from the Scioto plus the normal flowage from the Olentangy passing down the channel through Columbus to dilute the sewage wastes of the river below Columbus, where it receives the effluent from the outfall sewer at the city sewage-disposal plant.

The experience of the United States engineers in the Muskingum Watershed Conservancy District, with controlled and properly regulated reservoirs, has developed a system of water release and storage at the strategic moments, that bids fair to grow into a complete regulation of crests of dangerous and destructive floods on both the Ohio and the Mississippi Rivers.

This double outlet on the summit reservoir will permit the United States engineers to exercise a very complete regulation on the Sandusky River below the dam in that stream, since the auxiliary reservoir locations are not as available as they are on the Scioto.

The experience in the Muskingum is giving the United States engineers a demonstration of how to synchronize the reservoir control with storm intensity and dangerous flood crests, in the streams under control, with headwater floodcontrol reservoirs.

These criteria of multiple-purpose flood-control reservoirs are growing year by year as the plans of the United States engineers' headwater control develop and new experiences are encountered and the problems are solved

According to C. E. Sherman's reports on the 1913 flood, there were 75,000 cubic feet per second passing over Greggs Dam at the peak of the flood crest. Assuming that 75,000 cubic feet per second represents a lack of storage of about 150,000 acre-feet per 24 hours and that the flood flowage lasted for 3 days, then it would have required a summit reservoir storage, to prevent the inundation of west Columbus, with a flood-control reservoir that would hold back 450,000 acre-feet for a 100-percent control.

Calculations show that the proposed summit reservoir in the top 10 feet, between 890 and 900 feet mean sea level, would contain about 450,000 acre-feet of storage. But it has been suggested that the outlet channel down the Scioto should have a bottom level of 885 feet mean sea level or better. This would permit a lower draw-down as a flood is approaching the crest with a constant regulated flowage through the desilting flumes at the bottoms of both dams.

While the flood is cresting and filling the flood storage space above the conservation pool, the restricted spillways would be releasing a safe bank-full stream down both rivers under complete control of the United States engineers' attendants at the dams.

This is a recitation of the Muskingum Reservoir control system that is being followed for the control and regulation of floods in that conservancy district and it can be anticipated that the United States engineers would use the same regulation in the Scioto-Sandusky Conservancy District to control the floods. on both rivers.

Thus the top storage above the conservation pool becomes a detaining, retarding storage of flood run-off of the drainage area above the dams in both rivers, as shown by actual experience.

It may be necessary to build a diversion groin in the Scioto to accelerate the floodwaters toward the summit reservoir through the diversion channel, thus permitting a backwater release down the Scioto of retarded waters, through a restricted channel around the wing dam.

This wing dam should be built as an ogee dam with the over-fall crest at about 897 feet mean sea level, so that the top 3 feet below the 900-foot level would flow freely down the Scioto to the restricted spillway at the Bellepoint Dam, where if the emergency demands an accelerated release of excess floodwaters down the Scioto, the pen stocks or the desilting flumes at the bottom of the dam can be thrown wide open for free flowage under pressure.

The Scioto Channel can accommodate a greater volume of flood flowage than would be safe to be released into a flooded Sandusky, in case of an emergency. These suggestions are offered at this time to make it plain to the layman as to how headwater flood-control regulations can be developed by the United States engineers, when the local community cooperates with the Federal flood-control plans.

In my next report there will be a discussion of the smaller reservoirs in the Sandusky and its tributaries. Respectfully submitted.

DAVID C. WARNER,

Water Conservation Consultant in the Department of Public Works.

DECEMBER 5, 1945.

CENTRAL OHIO FLOOD CONTROL AND WATER SUPPLY

To the DIRECTOR OF PUBLIC WORKS:

In order for Columbus to have the benefit of all the year around flowage from the summit storage reservoir into the Columbus Bellepoint Reservoir, it will be necessary for the Scioto River and the Green Camp Diversion Channel to have a bottom level at 885 feet mean sea level so as to maintain an available draw-down of at least 5 feet from the conservation pool level of 890 feet mean sea level as mentioned in previous reports. That is why a groin or wingdam is suggested with an opening of at least 100 feet for constant slack-water flowage, so that all flowage above the minimum level of 885 feet will be diverted naturally into the summit storage from all three watersheds of the Scioto, Sandusky, and Tymochtee streams, to be spread out over the surface of the Summit Reservoir, so as to maintain a controlled low-water flowage down all three streams for all the beneficial uses of stored floodwaters for industrial, domestic, sanitary, and recreational waters.

The perpetual benefit of a stabilized supply of valuable and dependable, controlled normal flowage throughout the course of these two rivers across the central part of Ohio from Portsmouth to Fremont, is so far reaching that it is hard to estimate in dollar values the annual earnings because of the wide ramifications. of the accruing benefits that have to be estimated when flood-control calculationsof annual costs against annual benefits are set forth in a flood-control report.

The partial control of flood run-off and the many uses of the controlled waters in multiple-purpose flood-control reservoirs is such a new science in America, that the criteria for calculating all the benefits are not available with precedents of long-standing experience. One decade of engineering planning and practice in this national flood-control program by headwater reservoirs, does not answer all the questions and produce all the solutions to the great variety of water problems, that are being propounded and are the outgrowth of some catastrophies of either droughts or floods.

The Scioto-Sandusky Conservancy District was organized in 1934 by Alan Jordan to help solve some of these central Ohio water problems that have inflicted this part of the State with direct and tangible losses, that presage future disasters that must be prevented.

A large permanent conservation pool in the Summit Reservoir in central Ohio on the same level as the proposed Columbus Water Supply Reservoir at Bellepoint will mean that there will be a level body of water on the 890-foot mean sea level contour across the summit of the State from Bellepoint to within 6 miles of Upper Sandusky with a distance of over 40 miles to the headwaters on Broken Sword Creek.

When the top flood storage acreage above the conservation pool is reforested with wet land forests, that will protect the shoreland and help prevent the rapid silting of the main storage basin, then Ohio will have a water conservation project of outstanding values from all phases that cannot be appreciated until the coming generation realizes all the benefits.

A mere vision and word picture of such a water conservation project as this idea, that was originated by the late Prof. C. E. Sherman, is very hard to comprehend and sell to the general public, as was realized by Professor Sherman before he died.

He made the statement that "it may take another flood like 1913 and some more droughts like 1930 and 1934 before the State and the people in general will be able to comprehend the necessity of constructing the remedy for what ails the Scioto and the Sandusky Valleys." His was a vision that only just recently is being realized by the State and the Federal Governments. How we miss his wise counsel on water conservation and flood control is a tribute that is paid to his memory by his many conservation-minded friends who regret his passing.

As a close associate and a recipient of Sherman's broad wisdom, it is a rare privilege to try to give to this section of Ohio a small part of what he visioned. Over 40 years ago be began working on this idea of the central valley's water control for the prevention of floods and the storage of flood waters on the summit of the State for useful waters to the cities and towns down both rivers.

Before Gregg and O'Shaughnessy Dams were built, it was Professor Sherman's wise counsel that guided the planning engineers to give Columbus these dams as a beginning toward an adequate water supply.

His vision of the control of the summit run-off, with a slack water control of both rivers and reservoirs in all of the tributaries, would give to central Ohio a controlled water supply that would guarantee perpetual useful water for agriculture, industry, city water works, ground water restoration and recreation as a valuable byproduct.

The United States Army engineers have surveyed these two rivers and in their reports have given recognition to C. E. Sherman's reports, but because the Federal statutes confined these previous United States reports to flood control values only, they could not use the multiple-purpose benefits in their estimates of annual benefits against annual costs for favorable investments of Federal, State, and community improvements.

Since the passage of the first Federal headwater reservoir flood control law, dated June 22, 1936, there have been many broadening amendments so that now the local communities, districts, and States have a much wider range of cooperation and coordination with the United States engineers, to take advantage of every benefit that will accrue from a comprehensive water conservation program that can be developed on intra-State rivers.

The Federal flood control and water conservation program is experiencing an evolutionary growth and expansion that will some day give to the Nation and local communities all the beneficial uses of controlled flood waters.

It is very encouraging to realize that at long last the United States Congress has authorized the United States Army engineers to include in their estimates the many benefits that will accrue from a comprehensive program of flood control and water conservation.

A complete and comprehensive program of all the phases of water conservation for the central part of the State of Ohio as is outlined in the revised statute for the operations of the conservancy districts, has authorized the Scioto-Sandusky district board of directors to develop a cooperative and coordinated program of improvements in cooperation with every county, municipality, and individual landowner in the watersheds.

In connection with this statute are the many new State laws that make it possible for the State boards, divisions, and departments to cooperate, with their special services, to help in developing a comprehensively planned program for the benefit of all concerned.

Just to get a view of how interrelated such a comprehensive water-conservation program will integrate and obligate the close cooperation of all affected agencies, it will be necessary to consider the intricate and intermingled legislated conditions pertaining to the conservation of natural resources in Ohio.

In contemplating the development of a multiple-purpose Scioto-Sandusky Summit Reservoir for the realization of all the accruing benefits, it is necessary for the planning engineers to consider and recognize the causes and effects of damages and benefits with costs and direct and indirect accruing values and possible uses of the controlled flood waters.

If the waters of central Ohio are going to be controlled and regulated so that the Scioto and Sandusky River flood plains will be protected from excessive damaging floods in the future and, that these protecting works will be adequate enough to control enough of the excess flood run-off to supply a multiplied normal flowage down the main channels, then and then only can the economic growth of this part of the State be sure that neither floods nor droughts will interfere with the normal and anticipated expansion of population increase that will need this necessary protection and with it and from it will come the encouraging incentives that will guarantee economic expansion and natural development through water conservation.

Since the 1913 flood devastated the bottoms west of the river, Columbus has improved the channel through the city. To those who were here and witnessed that 1913 flood pass down the congested channel and then saw the backwater coming back up from Frank Road through the old channel and covering the whole west side to the foot of the hill, long before the waters broke over the NYC Railroad levee at Grandview Avenue, to come over on top of that backwater to sweep away the many homes and take the lives of 100 people, who had moved into their upper floors during the rise of the quiet backwaters from the south; there is a lesson to be learned from the fact that water seeks its level in backwater from floods.

That which has been done to the channel through Columbus will speed such a flood down into the flats below the city, so that the backwater from the south will come back up over the west side much faster than it did in 1913.

Nothing has been done in the headwaters of the Scioto to retard and hold back the Scioto run-off above the Grandview Avenue Bridge.

Besides, when the levee wall between the Pennsylvania Railway bridge and Broad Street Bridge was built, that section was purposely built lower, to form a long, open spillway so as to prevent the same kind of flood from again destroying the West Broad Street Bridge, and instead to permit such excess waters to pass down the old channel between the high school and Sandusky Street into the quiet backwaters that would be covering the west bottoms again. These conditions are brought to your attention because it must be realized that the river bottoms below Columbus are the same level that they were in 1913 and that when a speeded-up channel is forcing more floodwater into this natural spreading basin, that nature has created, then, its overflow backwaters will be greater and higher than they were when a congested channel was passing the floodwaters through the city down to the spreading bottoms, at a slower velocity in 1913.

Floodwaters should be retarded and controlled above in the headwaters, rather than given the speed to add to the destruction of down-river economic conditions.

The last two decades have witnessed the greatest drainage campaign of all time, in order to make work for WPA during the depression, and following the 1913 flood, when local communities desired to get rid of their floodwaters faster, with no thought of what would happen to their neighbors downstream. The 1937 and 1945 floods on the Ohio River are an outstanding example of what happens from a well-drained watershed with uncontrolled drainage.. The

Miami Valley and the Muskingum watershed conservancy districts illustrate in part, what headwater control can do for communities that have had the vision and enterprise to get this necessary protection.

The water shortage of January and February 1945 in the city of Columbus is a warning example of an opposite condition from 1913, that stands out in our memories, to add to the reasons why the wasting run-off of the upper Scioto must be controlled for future use of a growing Columbus as well as another repetition of a flood disaster, where both can be cured by the same remedy.

The recitation of all of these details is given at this time because Columbus again has the opportunity to cooperate with the other communities in the SciotoSandusky watershed conservancy district to obtain a resurvey of the upper part of the watersheds and thus let the United States engineers know that Columbus must have the use of the controlled summit waters and is willing to contribute its share of the cost in exchange for its protection against floods and thereby have the perpetual guaranty of an adequate and abundant water supply for future use and pollution dilution in low-water periods.

This lack of pollution dilution is costing the city of Columbus thousands of dollars annually for Scioto River pollution, because Columbus uses nearly all of the low-water flowage and leaves practically nothing to dilute the excessive wastes of a growing industrial city. This low-water flowage is only one more benefit against a known dollar damage, that is being accumulated in damage suits year after year against Columbus.

The question presents itself as to what would be the annual benefits against the annual costs for Columbus to acquire a guarantied large water supply with a measured flood protection, coupled with a constant increased lowwater flowage for sewage dilution and with it all thrown in for good measure, a much cleaner river passing through the city and the country below for recreation and down the river use for all beneficial purposes and added to all this a thirty-thousand-acre lake in central Ohio, where a motorboat can navigate these summit waters for over a 40-mile ride from Bellepoint to a point in Broken Sword Creek Valley east of Upper Sandusky.

These things will be available if this central part of Ohio will follow the advice of the late Prof. C. E. Sherman and show the United States engineers that Columbus and the communities of the Scioto-Sandusky watershed conservancy district are willing to cooperate for the building of the works.

The Muskingum watershed conservancy district had the cooperation of the State as well as the counties and communities with the United States Army engineers and the Scioto-Sandusky conservancy district must have it also.

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Section 6443-1, Ohio General Code, authorizes the county commissioners to cooperate with the several State and Federal agencies, "to formulate, create, and construct a complete or coordinated system of water conservation and flood control * with full power to maintain and carry the same forward and are further authorized and empowered * to provide their respective shares of necessary funds in accordance with law for the cost and expense of the formulation, creation, construction, and maintenance of such water conservation or flood-control system, which cost and expense shall include the cost and expense of all preliminary surveys of whatsoever kind or character necessary to the construction and maintenance of such water-conservation or flood-control system."

In accordance with this statute, the county commissioners of every county in the Scioto and Sandusky watershed are interested and authorized to cooperate with and to contribute to the necessary fund for making the general survey in order to cooperate with the United States engineers for a resurvey of the SciotoSandusky Conservancy District project for flood control and water conservation. According to the Federal flood-control statute dated December 22, 1944, the law states that, "it is hereby declared to be the policy of the Congress to recognize the interests and rights of the States in determining the development of the watersheds within their borders and likewise their interests and rights in water utilization and control, as herein authorized to preserve and protect to the fullest possible extent established and potential uses, for all purposes, of the waters of the Nation's rivers; to facilitate the consideration of projects on a basis of comprehensive and coordinated development; and to limit the authorization and construction of navigation works to those in which a substantial benefit to navigation will be realized therefrom and which can be operated consistently with appropriate and economic use of the waters of such rivers by other users."