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REMARKS PREPARED FOR

LIEUTENANT COLONEL ROGER C. HIGBEE

DEPUTY DISTRICT COMMANDER

U.S. ARMY CORPS OF ENGINEERS

LOS ANGELES DISTRICT

TESTIMONY FOR

CONGRESSIONAL HEARINGS ON

COLORADO RIVER FLOODING OF 1983

7-8 SEPTEMBER 1983

GOOD AFTERNOON MR. CHAIRMAN, MEMBERS OF THE COMMITTEE, AND LADIES AND GENTLEMEN IN ATTENDANCE. I AM PLEASED TO HAVE THIS OPPORTUNITY TO PRESENT YOU WITH A REPORT ON HOW THE US ARMY CORPS OF ENGINEERS HAS DEALT WITH THE COLORADO RIVER FLOOD SITUATION.

COMMISSIONER BROADBENT HAS ALREADY PROVIDED YOU WITH SPECIFICS ON MUCH OF THE COLORADO RIVER SYSTEM. I

PLAN TO PRESENT MAINLY ADDITIONAL INFORMATION, THEREBY

MINIMIZING REDUNDANCY.

THE US ARMY CORPS OF ENGINEERS HAS TAKEN ACTION IN TWO RESERVOIR REGULATION AND EMERGENCY OPERATIONS.

AREAS:

THE CORPS OF ENGINEERS RESERVOIR RESPONSIBILITIES

INCLUDE PRESCRIBING THE FLOOD CONTROL PLANS FOR THREE

PROJECTS PROTECTING THE LOWER COLORADO RIVER. THESE PROJECTS ARE THE BUREAU OF RECLAMATION'S LAKE MEAD ON THE MAIN STEM OF THE COLORADO RIVER PLUS THE CORPS OF ENGINEER'S ALAMO LAKE AND PAINTED ROCK RESERVOIR BOTH ON ARIZONA TRIBUTARIES. LET ME TAKE A MOMENT TO POINT OUT THE RESERVOIRS ON THE CHART I HAVE BROUGHT WITH ME

TO HELP CLARIFY THEIR RESPECTIVE LOCATIONS.

WATER CONTROL AT THE THREE RESERVOIRS IS WELL

COORDINATED TO MINIMIZE SIMULTANEOUS DAMAGING

RELEASES. FOR INSTANCE, DURING THE LAST SEVERAL YEARS THE CORPS HAS PROGRESSIVELY LOWERED ALAMO LAKE ON THE BILL WILLIAMS RIVER. THIS ACTION--ALTHOUGH

CONTROVERSIAL WITH RECREATIONAL INTERESTS-HAS REDUCED

THE RISK OF CONCURRENT FLOOD CONTROL RELEASES FROM HOOVER DAM AND ALAMO DAM SHOULD A VIOLENT ARIZONA RAIN FLOOD OCCUR. FOR EXAMPLE THIS MARCH A FLOOD PEAK OF 69,000 CUBIC FEET PER SECOND WAS REDUCED TO AN OUTFLOW OF ABOUT 1600 CUBIC FEET PER SECOND; A FLOW RATE THAT WAS READILY INTEGRATED INTO THE COLORADO RIVER WATER DISTRIBUTION SYSTEM. AT PRESENT, ALAMO LAKE IS NOT CONTRIBUTING ANY FLOW TO THE COLORADO RIVER.

LAST WINTER'S CENTRAL ARIZONA FLOODING DEVELOPED A LARGE IMPOUNDMENT BEHIND OUR PAINTED ROCK DAM ON THE GILA RIVER. A PEAK INFLOW OF ABOUT 29,000 CUBIC FEET PER SECOND WAS EXPERIENCED DURING FEBRUARY 1983.

SUBSEQUENT FLOOD CONTROL RELEASES FROM PAINTED ROCK WERE REDUCED APPRECIABLY FROM 4,500 TO 500 CUBIC FEET PER SECOND THIS JUNE TO MINIMIZE HIGH COLORADO RIVER LEVELS IN YUMA AS WELL AS IN MEXICO. THIS WAS AN

ACTION OF TRADE-OFFS WITH BENEFITS PROVIDED TO COMMUNITIES ON THE COLORADO RIVER AND BENEFITS REDUCED

TO COMMUNITIES ALONG THE GILA RIVER. PAINTED ROCK DAM RELEASES ARE PRESENTLY 1,000 CUBIC FEET PER SECOND. HOWEVER, DUE TO INTENSE DESERT EVAPORATION, A NEGLIBLE FLOW OF SEVERAL HUNDRED CUBIC FEET PER SECOND IS NOW REACHING THE COLORADO RIVER.

THE 1944 FLOOD CONTROL ACT ASSIGNED THE CORPS OF

ENGINEERS RESPONSIBILITY FOR THE FLOOD CONTROL

OPERATION OF ALL FEDERAL RESERVOIRS HAVING FLOOD

CONTROL AS A PROJECT PURPOSE. THIS INCLUDES LAKE MEAD FORMED BY HOOVER DAM.

IN 1977 THE BUREAU OF RECLAMATION AND THE CORPS OF
ENGINEERS JOINTLY INITIATED A STUDY OF THE FLOOD
CONTROL CRITERIA FOR LAKE MEAD. THE STUDY WAS

PROMPTED BY TWO CONDITIONS LEADING TO AN INEVITABLE
COLLISION COURSE: FIRST, CONSIDERABLE FLOOD PLAIN
ENCROACHMENT HAD ELIMINATED THE 40,000 CUBIC FEET PER
SECOND CHANNEL CAPACITY NEEDED TO IMPLEMENT THE, THEN
IN EFFECT, 1968 FLOOD CONTROL REGULATIONS:

SECOND,

LAKE POWELL WAS EXPECTED TO REACH A FULL CONDITION

WHICH WOULD RESULT IN THE RESUMPTION OF FREQUENT

HOOVER DAM FLOOD CONTROL RELEASES. THE STUDY AND

RESULTS, PRESENTED IN OUR JULY 1982 REPORT ENTITLED,

"COLORADO RIVER BASIN HOOVER DAM REVIEW OF FLOOD

CONTROL REGULATION," FORM THE CRITERIA GUIDING THIS
YEAR'S FLOOD CONTROL RELEASES.

THE STUDY WAS EXHAUSTIVE TAKING 5 YEARS TO COMPLETE.

I WOULD NOW LIKE TO TAKE SOME TIME TO DESCRIBE THE

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SUPPLY, OR POWER PRODUCTION OVER THE OTHERS OR WAS

DESIGNED TO REPRESENT A BALANCE AMONG THE THREE

PURPOSES.

ALTHOUGH THE PLANS DIFFER IN THE PURPOSES THEY FAVOR,

EACH HAS EIGHT ELEMENTS IN COMMON WITH THE OTHER.
FIRST, EACH ALTERNATIVE REQUIRES THAT A MINIMUM OF 1.5
MILLION ACRE FEET OF STORAGE SPACE IN LAKE MEAD BE

AVAILABLE ON THE FIRST DAY OF AUGUST OF EACH YEAR FOR

THE CONTROL OF RAINFLOODS.

Two, A 1 JANUARY MINIMUM STORAGE SPACE IS REQUIRED EACH YEAR FOR THE CONTROL OF SNOWMELT FLOODS DURING THE SPRING AND SUMMER. THE AMOUNT OF STORAGE SPACE VARIES FROM PLAN TO PLAN. IF NECESSARY, WATER WOULD BE RELEASED FROM THE DAM PRIOR TO JANUARY TO PROVIDE

THIS SPACE.

THREE, EACH PLAN SPECIFIED A MAXIMUM CONTROLLED

RELEASE.

FOUR, SPACE BUILDING RELEASES NEEDED TO INSURE

1 JANUARY STORAGE BEGIN ON 1 AUGUST OF EACH YEAR FOR UNDER THE PREVIOUS PLAN, SPACE BUILDING

ALL PLANS.

BEGINS ON 1 OCTOBER.

FIVE, THESE SPACE BUILDING RELEASES BETWEEN AUGUST TO DECEMBER, WOULD BE LIMITED TO THE GREATER OF EITHER 28,000 CUBIC FEET PER SECOND OR THE HIGHEST FLOOD RELEASE ACHIEVED SHOULD LAKE MEAD ENTER A SPILLWAY SURCHARGE CONDITION AS IT DID THIS JULY. UNDER THE

PREVIOUS PLAN, SPACE BUILDING RELEASES WERE LIMITED TO 40,000 CUBIC FEET PER SECOND.

SIX, EACH PLAN HAS A SET OF STEPPED RELEASES TO CONTROL SNOWMELT FLOODS. THE 28,000 CUBIC FEET PER

SECOND STEP REPRESENTS THE APPROXIMATE NON-DAMAGING HOOVER DAM RELEASE TODAY. THE RELEASE STEP OF 40,000 CUBIC FEET PER SECOND WAS USED IN THE 1930, 1957, AND

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