LADM NO. 1130-2-25 Brea Dam FCB O&M Manual 10-1971.pdf

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L A D M NO. 1130-2-25

OPERATION AND MAINTENANCE

MANUAL

, FOR

BREA DAM

SANTA ANA RIVER BASIN AND ORANGE COUNTY

EAST FULLERTON CREEK .IMPROVEMENT

CALIFORNIA

'L • ,·. : ~" • ~

" ... 1 1"·~.

DEPARTMENT OF THE ARMY LOS ANGELES DISTRICT

CORPS OF .ENGINEERS

OCTOBER 1971

P""I

LADM NO. 1130-2-25 Department of the Army, Los Angeles District, Gorps of Engineers October 1971

F 0 R E, W 0 R D

1. This manual prescribes standard procedures for the operation and maintenance of the federally constructed Brea ·Dam and Flood-Control Reservoir, Orange County, California.

2. The Operations Brapch of the Construction-Operations Division is responsible for the preparation of this manual and for keeping the manual up to date. Suggestions for revisions should be forwarded through channels to that branch.

3. All exhibits not attached to this manual may be found in the Operations Branch, Construction-Operations Division.

4. This manual rescinds LADM No. 1130-2-25, Brea Dam, dated July 1963.

~o/C~rf ~ H. McK. ROPER, JR.

LTC, CE

District Engineer

NO.

TABLE OF CONTENTS

TITLE

PART I GENERAL

Introduction

PAGE

1. Authority ........................ ~ ........... · ............. l

2. Purpose

3. Parts.of-manual .. ~·············~···········•.•:············· 1

4. Scope Of· manual ..••................••.•. , . . . . . . . . . . . . • • . . . 1

5.

6.

7.

8.

9.

10.

11.

12.

Project_ Description

Au thori za ti on . ......................................... · ..

Project location •••.. ~ ..•...••••...•.••..•..•••••..•••••.

Protection. proyi ded

Principle structures and equipment •.•.•....•••••.•.•.••••

Hydrographic installations ..••••.•••••••••.••••.•.•••..••

Communi ca ti on facilities~ ••..••••••••.•••...•••••.••.•••.

Construction history

Pertinent data ... -l

13. Recreational development •••...••.••..•.... ~

PART II OPERATION AND MAINTENANCE

1. Inform-ati·on ..... · .................. ~ ..... :

2. Reference drawings and manuals •..•.•..•..•.••••...•.••.• .- 5

3. Functions of the_fonstruction-Operations Division

4.

5.

6.

7.

8.

9.

10.

Fu~ctions of the Engineering Division ••.••.••••.••••••..•

Functions of the Real Estate Division ••••••••.•.•.••••• ~.

Functions of the U. s·. Geo 1 ogi ca 1 Survey •....••••.••••.••

Functfons of the Safety Office ..•••.•.•••••••••.•....•.•••

Du ti es of the Dam Opera tor ••••.••••..•••••• ~ •.••••...••..•.

Project and Reservoir Area

Dam • •••••••••••••.••••••••••.••••••••••••••••••••••••••••• s·addl e dike . ............. · .........................•..... •

'. 3

11 ·• Access roads . ••..•..•......•.•..•.......... .' • . • . .. • . • . . . • . . 9

12.

13.

14.

Fences . ••••..••.•..•.•... , .•.•.•.....••........•........•

Inspections and maintenance •.••••.•.•••.•••.•.••••••••...

Flood-emergency inspection •..•.......•..••..•.••....•..•••

Outlet Structures

15. Description

16. Approach channel ........................... ·-

17. Intake structure with tower and control house

18. Gated outlets

19. Ungated outlets

20. Outlet conduit

21.

22.

23.

Open lutlet channel •...••.••....••••.•.•.•..•.••••••••.••

Inspections and maintenance •••••••••••••••••••.•••••••.••

Spillway

Descri ptir on . ............. · · · · · · · · · · · · · · · · · · · · · · · · · ~· ·· ·· · · · ·

24. Approach channel . . . . . . . . •

25 . Control sect·i on . ......... ~ ................. • ....... 1• • • • • • 14

26. Exit channel ....... .' .......................... ~····~····· 14

27. Surface drains

28. Inspection and maintenance ••.•.•..••.• ~

Service Gates and Hoists

29. Description

30. Service g~tes.. • . • • . • . . • • • • • • • • . • . • . • . . • • • • • • . . • • • • • . . . • • 15

31. Hoists ......•...........................•.......•. ,.~

32. Electric motors and accesories

33. Test operation of gates

34. Five-year inspection and maintenance

Electrical Facilities

35. Electrical supply and services

36. Standby power un·i t. • . . . . . . . . • . • • . • • • • • • • . • . • • . . . • • • • • • • • • 17

37.. Switchboard

38. Light fixtures

39. Convenience outlets •••••.•.... ~

40 . Ground wire

.41. Operation of electrical facilities

42. Inspection, tests, and maintenance

43. Five-year inspection and maintenance

Hydrographic Installations

44. Slope and staff gages

45. Reservoir water-stage recorders

46 • Te 1 ema rk • • • • • . • • • • • • • • • • • • • • • • • • • • • • • • • • . • • • • • • • • • . • • • . • 20

47. Gate-opening recorders ..••••••••••.•..•.••••...•.•...• ~

48 •. Gate-opening ind1cators

49. Outflow gaging station ••••...•..•••.••.•...•••...•.• ~... 21

50. Standard rain gage

51. Automatic ·rain gages •••

••••••••••••••••••••••••••••••••• 21

52. Sedimentation monuments

53. Inspection, ·servicing, maintenance, and reporting

Communication Facilities

54. Radio station ............. , ........... -

55. Telephones

56. Maintenance of radio facilities

57. Telephone maintenance

Buildings

58. Dam Operator's house

59. Garage-shop building and equipment

60. Electrical service and equipment

61. Gas service and equipment

Water Supply and Sewage Disposal

62. Water-supply system

63. Sewerage system

64. Other improvements .. ............................. _ .. _

65. Inspection and maintenance ••.•.•.•....••.......••..•••.•. · 24

66. Miscellaneous

. · Fire-Fighting Equipment, Fire and Accident Prevent.ion . . ; .

67. Garage-shop building •••••••••••••••• ~······~············~ 2s·

68. Dam Operator's house •••••••••.••••. • ••••••. ·~ ••••••.•••••.•.•• · 2.6 ·

69 •. Contro 1 house a"d radio-equipment house· •••••• q • ••• · ••••• · 2~

70. Inspection, tests, an.d maintenance~ •• -~ ................... ; •• 26

72. Accident preve~tion ••••••. • ~ ••••••••• · •••.••••••• ~ ·• ••••• ~ 28

Foundation and Materials

73. · Instrumentation at Brea Dam .............................. · 30 ·

• J .

I'

74. · Responsibility for instrumentation measurements •.•.• ~·~·· 30

. ' I~

EXHIBITS

NO. TITLE

A. Proj.ect location ...................... "·••·••••e•••···· 1 Sheet

B. General Plan •.•••••.•.•. ~............................. 3 Sheets

C. Drawings, half-size (unattached) •••.•••.•..•••..•••.•.

D. Reference Manufacturers Manuals (unattached) •.••..•••.

E. Maintenance thart •••••..•• ~........................... 1 Sheet

F. Inspection check 1 ist................................. 1 Sheet

G. Test reports .... ·.·.·..................................... 1 Sheet

H. Gate operation., gate hoist •• ·.......................... 1 Sheet

I. Starting the UD 236 Diesel Standby-Unit............... 2 Sheets

J. Operation of Switchboard.............................. l Sheet

K. General Safety Requirements (EM 385-1•1 )(Unattached).

L. Foundation & Materials Instrumentation................ 1 Sheet

OPERATION AND MAINTENANCE MANUAL

FOR

BREA DAM AND FLOOD-CONTROL RESERVOIR

ORANGE COUNTY, CALIFORNIA

PART I - GENERAL

Introduction

1 . Authority. -- This manua 1 was prepared pursuant to ER 1130-2-304, dated 25 March 1966., which c:Jirects the preparation and prescribes the coverage of operation and maintenance manuals for completed civil works projects operated by the Corps of Engineers.

2. Purpose.-- The purpose of this manual is to provide guidance and instructions to the Dam Operator and District operating personnel for proper operation and maintenance of Brea Dam. These instructions will insure the continuous maintenance of structures and equipment, and their operation in such a manner and at such times as wi 11 obtain optimum benefits.

3. Parts of manual.-- This manual has been prepared in two parts:

(1) general description of the completed project, and (2) Operation and Maintenance instructions for the major and critical project equipment and facilities installed at Brea Dam. ·

4. Scope of manual.-- The scope of this manual is limited to essential operation and maintenance instructions, and describes the operating parts, their purpose, and technique of operation in sufficient detail to insure proper operation.

Project Description

5. Authorization.-- The Flood Control Act of 22 June 1936, as amended 28 June 1938, authorized a flood-control plan of improvement for pro tection of metropolitan areas in Orange County. Brea Dam and Flood Control Reservoir is part of this authorized plan.

6. Pro~ect location.-- Brea Dam is on Brea Creek, appro~imately one-hal mile north of the intersection of State Highway 72 and Brea Boulevard, and within the city limits of Fullerton; Orange County,· California. Brea Creek is a tributary of Coyote Creek, which is a tributary of the San Gabriel River. The .location of the project is shown on Exhibit A.

7. Protection provided.-- The. project was designed to protect the City of Fullerton and the highly developed areas adjacent to the lower course of Brea 'Cr~ek q,y,_redijcj_n_q,the flood flows to non-damaging states. The Reservoir Design Flood has a peak inflow estimated at 8,300 c.f.s. The Reservoir has a capacity of 4,018 acre-fe.et at the crest of the spillway (elevation 279.0) and a capacity of about 6,000 acre-feet at maximum water surface (elevation-287.7).

8. · Principle structures and eguipment.-- Principle structures and equipment include an earth-fill dam; an earth-fill saddle dike; an outlet works consisting of an approach channel, an intake structure with tower and control house, two gated outlets with gates and hoisting equipment, two ungated outlets, a standby power unit, a· service bridge from the top of the dam to the control house, a double-barreled conduit through the dam, and an outlet channel; aD ogee spillway; a Dam Operator's house; and a garage-shop building. (See Exhibit B.)

9. Hydrographic installations.-- Hydrographic installations include two reservoir water-stage recorders; two gate-opening recorders; an outflow gaging station; a standard glass-tube rain gage; a recording rain gage; and miscellaneous slope gages, staff g~ges, gate indicators, and sedimentation monuments.

10. Communication facilities.-- Communication facilities include a radio transmitting and receiving station and telephones at the control house and the Dam Operator's house.

11. Construction history.-- Copies of the contracts for Brea Dam are on file in the office of the District Engineer, Los Angeles Di.strict,· Corps of Engineers. Pertinent data on the principle contracts are as follows:

a. Dam and appurtenant work

Contractor:

Contract No:

Work Started:

Work Completed and Accepted:

Winston Bros. Co.

W-509-ENG 1073

1 July 1940

30 March 1942

-b. Service gates - fabrication

Contractor:

Contract No:

Work Started:

Work Completed and Accepted:

Philips & Davies, Inc.

W-509-ENG 1121

.- 19 September 1940

18 September 1941

c. Remodeling Dam Operator's house

Contractor:

Contract No:

Work Started:

Work Completed:

Work .Accepted:

12. Pertinent data.--

A. J. Givson

W-509-ENG-2314

25 April 1942 26 June 1942 21 September 1941

Drainage area .......... ~.... . ............. · ....... sq. mi . . . 22 .O Reservoir: · Elevation

Streambed at dam •.••..•• : ••....••..•• , •.... ft., m.s.l... 205.0 Spillway design surcharge· level ••••.•••..• ft., m.s .1... 287. 7

Area (Survey of. June 1964) i . · s.p.j.1 lway cres.t.·~-.. •·• .·,., .: ........................... . ac... l61 Spillway design surcharg~ level ..... ~ .....•........ ac... 216 Top of Dam .............. : .......................... ac... 269

Capacity (Survey of June 1964) Spillway crest ........•. i •••••••••••••••••••••• ac. -ft. . . 4 ,018 Spillway design surcharg~ level ............... ac.-ft... 5,660 Top of dam.· ............. ! •••••••••••••••••••••• ac.-ft... 7,439 Sedimentation allowance.: .... ~ ............. ~ ... ac.-ft... 1,200

Dam-type .................... ; ................................. Earthfill Top elevation ........... : .................. ft., m.s. l.. 295.0 Height above original streambed ..•.•.........•. ; .. ft... 87 Top length .......•.•..•. :...... ft.,appro¥... 1,765

Spillway-type ...•..•..•..•. .:. ................. Overflow concrete ogee Crest elevation ......... : ................... ft.,m.s.1... 279.0 Crest length ........... . i •••••••••••••••••••••••••• ft... 150 Design surcharge on spil!lway crest ..••........•... ft... 8.7 Discharge at design surdharge ...•.•..••......... c.f.s... 14,000

Outlets: ! I

Ungated: , Number • •••••••.•.•••...• : • • . . • • • . • • • . • • • . • • • . . • . . . . • • . • . .2

• Si ze . ••.••.......•.•.... ! •••••••••••••••••••••••••• ft. .. . 3. O x 2. 5 Entrance invert elevati(ln .................. ft.,m.s.l... 251 Gated:

Number ...•.......•..••• ~ Size ................... J ........................... ft... 5 x 8 Gate tvne ............ . J ••••••••• •••••••••••••••••• Vertical lift Entrance invert elevation .....•..•..•....... ftqm.s .1... 208

Conduits Number • ................ ~ ..•................... ·• ..

Size ................ ~ ... , ...................... ft .. .

Max. LengtRpa. f t·rn·l.. · .. !.,!1.,..., .• _.,· ~·"· ••. •t ~ ...... ·-~.~· ........................ ft ..• imam c c ., ... 1. sp1 1way cres .•..............•. c.f.s ..• Regulated capacity at spillway crest., .............. c.f .s .. .

z 5 ~ _8

!,SQO

1,400

Reservoir design flood: (original design) Dura ti on • .••••••...••••.•.......•...•.......•••..... days .. .

Tot~l volume ...................................... ac.- ft .. .

I -nfl ow peak ... ~ ............................... · .... c . f . s .. .

Outflow peak .................................... -.. c.f.s . . .

Re due ti on in peak • ..•••.•..........••...•.......•. c. f. s .. .

Spillway design flood:

Du'ra ti on . ...••.••...• ; ...........•................. hours .. .

Total vo 1 utne . ................................... a·c. -ft Inflow peak . .......................•. ~ ............ c. f. s .. .

0 u tfl ow peak ..................... ~ ................ c . f. s .. .

Reduction in peak ............................ , ..... c. f .s .. .

Standard project flood: (current flood-control operation) Dura ti on . ................................... · ..... . hours . . .

To ta l vol ume • . • • . • • • • • • • • • • . . ••.•••••...•.•. ·• • . • a c . -ft Inflow peak ..•••...•.•..•.•....•................... c·. f .s .. .

Q.utfl"qw peak ...... : .............................. . c. f .s .. .

Reduction in p.eak •... ~ .•.•.•.......•.........•.... . c. f .s .. .

Maximum probable flood:

Dura ti on . ......................................... hours .. .

Total volume .................................... ac.-ft Inflow peak.· . ..................................... c. f. s .. .

O~tflow peak ...................................... c.f.s .. .

Reduction in peak ...•.............................• c.f.s .. .

9,440 8,300 1,400 6,900

12 ,360 16,800 14,500 2,300

8,260 8,000 4.280 3,720

8,200

37,000 27,000 10,000

13. Recreatio.nal development.-- A recreational area of 182 acres was granted the City of Ful 1 erton, Department of Parks and Recreation, by the Corps of Engineers on 3 December 1959 for development of recreational facilities within the reservoir area.

PART I 1: - OPERATION AND MAINTENANCE

General

1. Infonnation.-- Special terms used in this manual are:

a. 11 Flood Season 11

· - refers to the period from 15 October to e 15 April ·When most past floo.ds have occurred.

b. "Emergency Flood Conditions" - refers to periods· during which the reservoir water surface rises above the crest of the spillway at elevation 279.0. All elevations refer to "mean sea level" datum.

2. Reference drawings and manuals.-- Drawing file numbers in this manual refer to nas-'constructed 11 drawings; half-size. reductions are included as Exhibit C and are separately bound. Drawings, manuals, and instructions for manufacturers• equipment are listed in Exhibit D and are on file in the District Office, Maintenance .·Section, and at the project. ·

3. Functions of the.Construction-Operations Division.-- Operation -and maintenance and all inspections are under the supervision of the Construction-Operations Division, which assigns this responsibility to the Operati.ons Branch. The general duties include the. following:

a. The Operations Branch shall train key personnel in order that regular inspection,' operation and maintenance work will be performed efficiently and to insure that unexpected problems related to flood control may be handled in an expeditious and orderly manner. The men shall become familiar with the provisions of this manual, the supplements A, B, and C of LAD OM 500-1-1, and the "as-constructed" drawings. · ·

b. The Operations Branch shall report violations of outgrant terms to Real Estate Division for official action when they cannot be handled informally.

c. The Operations Branch prepares and executes all flood-fighting plans and through the Regulation and Meteorology Section directs the Dam Operator or his assistant in the operation of the ·gates. The above section keeps records of reservoir stages, inflow to the reservoir, releases through the outlet structures, and spillway flow.

d. The Regulation and Meteorol,ogy Section, Operations Branch, is responsible for the inspection, servicing, and maintenance of all hydrographic installations and radio installations. (Their routine inspections are made by the Dam Operator.)

e. Periodic inspections shall be made by the Engineering Evalua tion and Inspection Section, Operations Branch, in order to determine maintenance measure,s necessary to insure serviceabi 1 i ty of the works in time·of flood. Such inspections shall be made immediately following each major highwater period, at intervals not to exceed six.months, and at such other times as may be necessary.· Immediate steps shall be taken to correct dangero·us conditions disclosed by such inspections, and regular maintenance repair ~easures shall be accomplished during th~ appropriate season as scheduled by the Chief, Operations Branch.

All repairs shalJ be made in accordance with standard engineering practice to line, grade, and quality and 'in accordance with relevant de~ails shown on . 11 as-~onstructed

11 drawings, Exhibit C.

f. The Engineering Evaluation and Inspection Section, Operations Branch, reviews plans and furnishes comments to Real Estate Division on requests from public or private interests for collateral use of land and water areas and performs inspections during construction to assure compliance with approved plans.

g. The Maintenance Section, Operations Branch, shall establish a file of all .reports and records concerninS the maintenance and operation of the project works. (See Exhibit E.) ·

4. Functions of the Engineering Division.--

a. Conducts or participates in periodical condition surveys of the project with representatives from Construction-Operations Division, South Pacific Division, and Office of the Chief of Engineers. These surveys serve a two-fold purpose: (1) ascertain the condition of the various parts of the project, and (2) see that all repairs and improve ments have been carried out that were previously recqmmended.

b. Performs engineering review of plans of proposed development on project land or water areas, as requested by the Construction Operations Division.

c. Furnishes engineering comments on request.of public or private interests for collateral use of land and water areas as requested by Construction-Operations Division. ·

d. Reports to Construction-Operations Division all trespass or violation of outgrants discovered by Engineering Division personnel.

5. Functions of the Real Estate Division.--

a. Processes a 11 permits, 1 i censes, easements, or 1 eases through appropriate channels and administers completed instruments.

b. Insures compliance through periodic inspections and acts upon all violations _of outgrants.

·c. Furnishes the Construction-Operations Division copies of all permits, licenses, easements, or leases.

6. Functions of the U. S. Geological Survey.-- By a9reement with the Corps of Engineers, the 0. S. Geological Survey (USGS) services the outflow gaging station below Brea Dam and makes di'scharge measure ments. Outflow records are published in their "Water Supply Papers.11

7. Functions of the Safety Office.-- A11 functions involving safety are under the supervision of the Chief, Safety Office. The Safety Office shall perform periodic inspections to insure compliance with appropriate safety codes and standards of all activities in the project area.· ·

I

8. Duties of.the Dam·Operator.-- The Dam Operator or ·his alternate 1' is required to perform the following duties: (Hereafter Dam Operator or his alternate will be referred to as Dam Operator.)

a. Be present at the dam when rainfall or runoff occurs.

b. See that all equipment at the project, including·~ecording and indicating gages, gate mechanism, power units, radio, etc .. is in operating condition •.

c. Operate the gates fo accordance with instructions from the Regulation and Meteorology Section, Operations Branch, Construction Operations Division.

d. In the absence of communications with the Operations Branch, Construction-Operations Division, or in the absence of a representative from that group, follow the fixed gate operation schedule posted in the control house.

e. Service all gages and recorders, wind the clocks, install new recording paper, etc.

f. Guard the proj~ct against vandalism, sabotage, and fires.

g. Guard against unsafe conditions in the project area.

h. Report on trespassing and encroachment on rights-of-way.

i. Maintain records, including water surface 'elevations, outflow gage heights, preci.pitation amounts, gate openings, and· log all radio and telephone calls on prescribed forms.

j. Keep premises and equipment clean and in good repair; painting will be performed by the Dam Operator when necessary. On larger jobs requiring sandblasting and painting, the maintenance crew will assist.

k. Periodic inspections of structures, equipment, and the project area shall be made by the Dam Operator to determine maintenance measures that.are required. These inspections during the non-fl0od seasons shall be made at intervals of not more than 90 days, during the flood seasons at intervals of not more than 30 days, and also immediately following each flood. More frequent inspections shall be made· if ~eguired for the safety and efficient maintenance of some features of the proj~ct. · During each i nspecti.on '· i terns requiring maintenance shall be checked and described on the inspection check list included as Exhibit F. After each inspection, one inspection check list shall be promptly submitted to Chief, Engineering Evaluation and Inspection Section, Operations Branch, through the Chief, Maintenance Section. Maintenance shall be performed by the Dam Operator, if feasible. Note: If maintenance requires additional labor or equipment, the Dam Operator shall notify the Chief, Maintenance ·section, of the recommended maintenance measures required. Normal maintenance shall be made without delay.

1. The Dam Operator shall test operate the service gates and electrical facilities in the control house every 30 days and the standby power unit every 15 days. Test operation reports (Exhibit G) shall be completed in triplicate after each test. One copy shall be promptly submitted to the Chief, Maintenance Section, one copy to the Chief, Engineering Evaluation and Inspection Section, and one copy kept on file in the Control House of the dam.

Project and Reservoir Area

9. Dam.-- Brea Dam is a compacted earthfill structure approximately 1,76-s-feet long and 87 feet high. The upstream face is covered with a 2-foot layer of graded granite riprap roughly placed over a 12-inch gravel backing. Th.e slope -of tlie upstream face i's 1 on 4 from the toe to elevation 255.0, and 1 on 3.3 from elevation 255.0 to the crest, elevation 295.0. The downstream face is covered with a 2-foot gravel blanket, with a slope of. l on 4 from the toe up to a· 12-foot wide berm at elevation 255.0 and 1 on 3 from the b'erm to the crest. A rock drain, cut in the original ground ur.der the dam, is parallel to and 110 feet

L downstream from the axis of the dam. · A 36-inch re.inforced concrete pipe connects the rock drain with a manhole at the downstream toe of the dam. The manhole is drained into the outlet channel by a 12-inch corrugated metal pipe .with automatic drainage gate. See drawings 435/8, 435/21, and 435/4 of Exhibit C.

10. ·Saddle dike.-- The saddle dike was constructed in lieu of re locating the Umon Pacific Railroad trackage just to the west of it.

The dike is located on the west side. of the reservoir, less than one mile north of the dam, and .is approximately 650 feet long and 39.5 Jeet high. Both faces are covered with an 18-inch gravel blanket, witt! a slope of l on 3 from the. base to elevation 285.0.and l on 2~ from elevation 285.0 to the crest. elevation 295 .O. One 30-1nch and two 48-inch corrugated rrietal drainage pipes pass through the dike and are equipped with automatic drainage gates on.the ends of the pipes inside the reservoir. These gates permit drainage into the

.res'ervoir, but. prevent flow in the opposite direction (see drawing 435/32;

Exhibit C).- It is extremely important that these drainage facilities be kept operable at all times in order to prevent damage to the Union Pacific tracks by flooding during periods of high water in the reservoir.

11. Access roads.-- Access roads include the following: (a) an access road extending southeastward from its junction (about 600 feet downstream from the crest of the dam) with State Highway 72, past the Dam Opera tor 1s house, and thence to the sou teas t end of the dam;

(b) an access road extending southeastward from State Highway 72 to the northwest end of the dam; {c) an access road, about 300 feet long, extending northeastward from State Highway 72, through the Union Pacific Railroad rights-of-way, and thence to the west end of the saddle dike; and (d) gravel-surfaced roadways, 9 inches thick, extending along the crests (20 feet wide) of the dam and the saddle dike.

(See drawings 435/6, 435/21, and 436/69 of Exhibit C.)

12. Fences.-- Project ferices include rights-of•way fences and safety guard fences. The rights-of-way fences consist of four barbed wires strung on wqod posts. The safety guard fences, which are 4 feet high and 8 feet high, are chain-link fences with steel posts; they are topped with barbed wire.· A safety guard fence 8 feet high, with posts set in concrete, is along the east rim of the spillway excavation;

and safety guard fences 4 feet high, with posts cement-grouted into pipe sleeves, are along the tops of the concrete walls on.each side of the outlet channel and the spillway-control section. (See drawings 435/6, 435/20, 435/43, 435/52, 436/56, 436/57, and 436/69 of Exhibit C.)

13. Inspections and maintenance.-- The Dam Operator shall perf,orm periodic inspections and maintenance and shall .complete inspection check list as shown in Exhibit F. Maintenance work is described in detail in the following paragraphs:

a. Embankments.-- Maintenance methods for repair or reconstruction of the embankments shall depend upon the extent of the damaged section.

If the embankment damage is small, sand and gravel or other coarse granularimaterial may be placed in 6-inch layers to restore th~ embankments. If the damage is 1 a rge, the fill sha 11 be made in the same manner as the original construction; homogenous material from borrow pits approved for the project shall be placed in uniform horizontal layers not more than 6 inches in depth and compacted to a density equa 1 to the ori gi na 1 embankment sec ti on.

b. Concrete and riprap.-- Damaged concrete or riprap structures shall be repaired promptly. Broken concrete surfaces and exposed reinforcement .steel shall be thoroughly cleaned by chipping or sandblasting and shall be built up to the original dimensions;

pneumatically placed portland-cement mort~r is satisfactory for this work. Small cracks in .the concrete may be filled with asphalt.

· Any indicatio.n of settlement, uplift, or failure of concrete structures shall be reported to the Chief, Operations Branch.

c. Embankment drains.-- A system of pipes ranging in size from 12 inches to 36 inches drains the embankments. The 12-inch and 18-inch perforated ·corrugated metal pipes are surrounded by l~ to 3-inch aggregate which in turn is surrounded by a 9-inch layer of #4 to 1~ inch aggregate and a 9-inch layer of sand. The 36-inch pipe is of extra heavy reinforced concrete in 4-foot lengths and a manhole is located at the end of the pipe where it reduces to 12 inches in size.

(See drawings 435/21 and 435/4 of Exhibit C.) It is improtant that this manhole normally be kept covered, s i nee when open,· it constitutes a possible trap for children. Any indication of seepage through the dam shall be reported to the Chief, Operations Branch. Automatic drainage gates on the corrugated metal drainage pipes from the embankments shall be oiled and checked during each inspection.

d. Access roads and berms.-- Access roads and embankment toe berms .shal 1 be adequately maintained for vehicular travel so that ordinary maintenance of the project and flood-fight\ng operations wi 11 be facilitated. The crests with the roadway on the dam and the saddle dike shall be well crowned and maintained to drain readily.

e. Fences.-- Maintenance of the rights-of-way and safety guard fences shall include keeping (a) line posts firmly set and gates hung in good alinement; (b) barbed wire tight and broken strands repaired; (c) corner posts, gate posts, and braces firmly set; (d) posts, braces, and gates that require paint properly brush painted;

(e) chains and locks attached to all gates; and (f) gate keys available at the Dam Operator's' house to permit authorized travel throughout the property.

f. Vegetation. -- Weeds and brush on the· embankments sha 11 be mowed in May and August, and more often if they interfere with proper inspection of the embankments and adjacent areas -for settle ment, seepage, ·and burrowing animals. After mowings the weeds and brush shall be removed to an approved disposal area.

g. Burrow~n animals.-- Burrowing animals in or near the dam or the saddle dike shal be exterminated. Their runways and dens shall be opened up and thoroughly compacted at the same time they are. backfilled. Trapping and poisoning may be used for the extermina tion of burrowing animals. Information about other methods of animal extermination may be obtained from the county agricultural agent.

h. Hazardous obstructions.-- Reservation area used by authorized personnel shall be kept free from obstructions that may cause injury or impede inspections, maintenance, or flood-fighting operations.

Materials and auxillary construction equipment shall be stored in such a way that they a~ not hazardous to personnel or capable of floating into the gate structure.

14. Flood-emergency inspection.--

a. During flood periods, the embankments shall be patrolled continuously to 1ocate possible sand boils or unusual wetness of the downstream slope and to take appropriate corrective measures for the following condi~ions~

(1) Indications of slides or sloughs developing.

(2) Wave wash or scouring action.

(3) Other .conditions whi'ch might endanger the structure.

(4) Inadequate labor and materials to meet all contingencies.

Immediate ·steps shall be taken to control any condition which endangers the embankments and to repair the damaged sec ti on.

b. The project works shall be continuously patrolled during periods of flood flow during which the water stage in the reservoir :* reaches or e ceeds elevation 275.0. A store of su lies and e ui ment avai ble for emer ency oo - i hting o erations an emer ency rep~irs shall be maintarne . In 1s connection, a copy o · e atest

)revised "Natural Disaster Activities Memorandum OM 500-1-1 11 shall be consulted for suggested methods of combating flood conditions.

Outlet Structures

15. Description.-- The outlet structures inc·lude an approach channel, an intake structure with tower and control house, a double-barreled conduit through the dam, and an outlet channel. Descriptions of the outlet structures are given in the following paragraphs.

16. Approach channel.-- The approach channel is lined partly with rock and partly with reinforced concrete. The rock.,. lined sec ti on, which is 100 feet long, is paved with 12-inchJJngrouted rock over a 6-inch gravel backing. The side slopes of this section extend up to elevation 220.0; they are warped to make a smooth transition from the upstream natural-earth channel to the 1 on 2 side slopes of the concrete-lined section. The concrete.,.lined section, including intake structure wing walls, extends 67 feet upstream from the intake structure. (See drawing 435/8 of Exhibit C.}

17. Intake structure with tower and control house.-- The intake structure with tower and control house is a reinforced-concrete structure with a base slab 6 feet thick, 63 feet long, and 54 feet wide. The top of the control house is 105.5 feet above tne top of the base slab, which is the_intake invert (elevation 208.0). The inside of the contro 1 hous·e is 22 feet wide, 28 feet long, and approximately 16 feet ·high. A .steel-girder service bridge, which extends from the Jop of the dam to the control house, is about 111 feet 1 ong; the bridge is designed for H-10 loading. The bridge has a concrete deck; and an ll-foot ·roadway, two sidewalks 2 feet wide, and steel pipe side railings set in concrete posts. (See drawings 435/8, 435/3, 435/15, 435/16, and 435/47 of Exhibit C.} ..

18 .. Gated outlets,.,.- Two 5- by 8-foot gated outlets control outflow from the reservoir for water-surface elevations ranging from elevation 208~0 the elevation of the intake invert, to elevation 251.0, the elevation of the inverts of the ungated outlets. The gated out lets are separated by a concrete pier 5 feet thick. About 40 feet downstream from the gates, the two 5- by 8-foot parallel conduits convey the flow into the double-barreled outlet conduit, which extends through the dam. Separate 10-inch air-vent pipes are provided for each of the gate wells and for each water conduit behind the gates. (See drawings 435/15, 435/16, 435/17, and 435/46 of Exhibit C.)

19. Ungated outlets.-- Two 3- by 2.5-foot ungated outlets, outside and above the gated outlets, permit flow to bypass the gates when the reservoir water surface reaches and exceeds elevation 251.0. These outlets prevent permanent storage above that elevation. Water flows over the sill of each ungated outlet into a 4- by 5-foot vertical shaft, which extends 2 feet below the intake invert, elevation 208.0. Each shaft is provided with a lQ-inch air-vent e pipe. At the'elevation of the intake invert, each shaft drains the water into separate 3- by 4-foot conduits, which converge with smooth horizontal curves into the adjacent conduits from the gated outlets. The combined computed discharge of the two ungated outlets is 590 c.f.s. when the reservoir water surface reaches the spillway crest, elevation 279.0. (See drawings 435/15, 435/16, and435/45 of Exhibit C.)

20. Outlet conduit.-- The outlet conduit consists of a double- . barreled conduit, each barrel of which is 5 feet wide by 8 feet high.

The barrels are separated by 2.5 feet of concrete. TransitiOn conduits from the gated and ungated outlets lead the f1ow into the outlet conduit. The i n·verts of the intake and the transition sec ti on are level at elevation 208.0. About 64 feet downstream from the gates and at the end of the transition section, 14 monolithic sections of the conduit extend 420 feet through the dam on a uniform slope of 0.00238 to elevation 207.0 at the invert of the outlet portals. The conduit discharges into the open outlet channel. (See drawing 435/19 of Exhibit C.)

21. Open outlet channel.-- The concrete-lined part of the open out let channel is a chute 12.5 feet wide and 425 feet long, with depths ranging from 9 to 12 feet •. Flow continues from the concrete section through a trapezoidal section, 60 feet long and lined with derrick stone,_ to the existing. natural channel of Brea Creek. The invert of the concrete secti'on·has a uniform slope of 0.01867 for a distance of 375 feet downstream from the outlet protals. The inverts of the last 50 feet of concrete sec ti on and of a 11 the s tone-1 i ned sec ti on are level at elevation 200.0. Hydrostatic pressure behind the walls of the concrete section is prevented by two 8-i nch open-joint ti 1 e drain pipelines, which discharge into the derrick stone section. A concrete bridge, on the road to the Dam Operator's house, spans the concrete channel. This bridge; which has a clear width of 12 feet is about 70 feet upstream from the end of the concrete section. (See drawing 325/20 of Exhibit c.) -

22. Inspections and maintenance.-- The Dam Operator shall inspect each year, before the flood season starts, the interior of the outlet and the full length of the double-barreled conduit and shall complete inspection check list as shown in Exhibit F. In addition to inspection and maintenance work previously described for embankments, concrete and riprap structures, and safety guard fences, the Dam Operator shall perform maintenance work pertaining mostly to the outlet structures.

(See drawings 435/19 ~nd 435/20 of Exhibit C.)

a. Channels.-- Channels shall be kept free of driftwood, trash, silt and other debris. Driftwood, brush, weeds, and other combustible and incombustible accumulations of trash shall be hauled away-and dumped in approved disposal areas.

b. Weep holes.-- Weep holes in the linings of the approach and spillway channels shall be kept open. Plant growth, birds' nests and animal-den accumulations shall be removed from the weep holes, using weed killer to keep down plant growth, and a piece of heavy wire bent into a hook at one end to remove birds' nests and animal-den accumula tions. Silt deposits shall be removed from the holes by flushing with a hose·and nozzle.

Spillway

23. Description~-~ The spillway, which is east of the d m embankment, includes a trapezoidal approach channel, a rectangular co trol section, and a trapezoidal exit channel. (See drawings 435/6 and 35/24 of Exhibit C.) The design flood outflow is approximately 14,000 cubic feet per second, with a depth over the spillway crest of 8.7 f et.

24. Approach channel.~- The approach channel, which is trapezoidal channel with side slopes of l on 2, is about 640 feet lon ; it has a bottom width of 150 feet. The first 600 feet of channel onsists of unlined excavation in natural earth; and the last·40 feet is lined with reinforced concrete. About 30 feet upstream from the fac of the ogee of t~e spillway, the trapezoidal approach channel ends an the rectangular control section begins. Upstream·from the face of the og e, the spillway invert is level at elevation 267.0.

25. Control section.-- The control section of the spill ay is a reinforced-concrete structure approximately 675 feet long with a clear width of 150 feet between vertical walls. A steel sheet- iling cutoff reduces seepage under the structure. A system oi open-joint tile and gravel drains under the floor of the control section protects the spillway against uplift pressure. The ogee crest, which is 12 feet above the invert of the approach channel, is at elevation 279.0 and the toe of the ogee is at elevation 275.0. The control section extends .downstream approximately 288 feet on a 0.0506 slope, and approximately 303 feet on a 0.0746 slope. The control section terminates in an energy dissipating deflecting bucket. The lip end of the bucket is at elevation 240.0. The bucket is protected from underscour by a steel sheet-piling cutoff and by the derrick stone apron downstream.

26. Exit channel.-- The spillway exit channel, which is a trapezoidal channel with l on 2 side slopes, deflects the southward flow from the control section and carries it southwestward into the flood plain of Brea Creek. The first 50 feet of the exit channel is lined with derrick stone, and the rest is unlined excavation in natural earth. The invert of the stone-lined section has a slope of 0.04; the invert of the excavated unlined section, which is at elevation 238.0, is level until it reaches the original ground surface. The bottom width of the channel ranges from 150 to 185 feet.

27. Surface drains.-- A system of refnforced coAcrete-lined surface drains protects the excavated banks on each side of the spillway. (See drawing 435/52 of Exhibit C.) ,

28. Ins ection and maintenance.-- The Dam Operator shall perform periodic inspections an maintenance according to the duties of the Dam Operator, and shall complete inspection check list as shown in Exhibit G. The spillway shall be inspected at least once each year during the dry season. Inspection and maintenance of concrete and derrick stone structures, channels, and weep holes, and the elimination of hazardous obstructions is similar to that desGribed for the inspection and maintenance of open outlet channel. Additional maintenance work

14' that pertains to the spillway is given in the followi_ng paragraph:

Surface dr_ains.-- -The surface drains on each side of the spillway shall be kept free from weeds, trash, and accumulations of soil from the excavated banks. Broken or displaced-concrete shall be promptly repaired.

Service Gates and Hoists

29. Description.-- Two 5- by 8-foot caterpillar-type gates, which are operated by motor-driven hoists, control the. outflow from the reservoir. The design head,_measured from the water.surface at maximum spillway flood to the center of the gates is 76 feet. (See drawings 435/48 and 435/49 of Exhibit C.)

30. Service gates.-- Each service gate, which weighs approximately 10,000 pounds, is desig'ned to be self-closing under all hydrostatic heads. The gate' leaves are structural steel. The gate frames and extensions ·to the gate frames are high-strength cast iron, and the seal plates on the gates and gate frames are bronze.

31. Hoists.-- Drum-type hoists permit either motor or manual operation of the gates. Motor operation lifts or lowers each gate at a rate of about 1-foot per minute. Hand cranks, mechanical brakes, pawls .• and ratches permit manual operation of each gate during power-service fai 1 ures and remova 1 of motors for repair. High-pressure grease fittings permit l ubri cation of a 11 moving parts. Hoists are equipped with pushbutton controls ~and automatic e 1 ectri c brakes, as we 11 as mechani ca 1 1 oad brakes .•

32. Electric motors and accessories.-- Ea'Ch hoist is operated by a General Electric K. R. splashproof, ball-bearing, 3 hp. motor., which operates on 3-phase 440-volt·service. Each motor is designed to lift a gate at approximately 1-foot per minute~ Each hoist motor is provided with a reversing magnetic starter and a pushbutton control station. Four pushbuttons are marked, respectively, 11UP 11

11 DOWN 11

11STOP 11

, and 11 UP-INSP 11

• Operation of the 11 UP-INSP 11 pushbutton requires the use of a key. CAUTION: Before using the 11 UP-INSP 11 pushbutton, ' the cover plates over the gates shall always be removed; and the gate-opening indicator cables disconnected. An electric brake mounted_ on the shaft.of each hoist motor automatically stops~ the hoist within 3-seconds whenever the power supply is interrupted; each break permits electrical and hand operation. Limit switches on.each hoist opens the hoist motor circuit and apply the electric brake when the gate reaches a fully closed or fully open position. Power to each hoist motor is supplied through an air circuit breaker mounted on the control-house switchboard.

33. Test operation of gates.-- The Dam Operator shall test operate the two service gates on or near the first day of every month and shall complete and transmit test-operation reports as described in Duties of the Dam Operator of this manual. Each month one gate shall be operated by standby power and the other gate shall be operated by Edison Company power. The source of ppwer used to operate each gate shall be alternated from month to month. (See Exhibit H which illustrates operation of the gate hoists.) Maintenance work pertaining to service gates and hoists is described in detail in the following paragraphs:

a. General.-- The gate and hoist assemblies shall be maintained in the best possible operating condition. They shall be tested once every month and the report {Exhibit G) sh al 1 be submitted to the Chief, Engineering Evalua~ion and Inspection Section, Operations Branch, through the Chief, Maintenance Section. Loose, damaged, unserviceable, or missing parts shall be promptly tightened, repai.red, or replaced.

b. Gates.-- Gates must come to a true watertight closure against the bottom seal. the Chief, Operations Branch, shall be notified whenever the gates fail to close tightly or whenever the seals are damaged. Gate-seal surfaces shall be kept clean and free from mud and sand, and the bottom sealing surface shall be kept free from rocks or other obstructions. To minimize the adhesion of abrasive dust and sand, the gate seals, frame seals, gate wheels, and gate wheel pins shall NEVER be lubricated.

c. Hoists and motors.-- Hoists and motors shall be kept properly lubricated. Before attaching the grease gun to the grease fitting, wipe the fitting carefully to remove all accumulated dirt and· grit.

Each hoist.assembly shall operate smoothly and without abnormal noise or vibration. The gate-opening indicators, shall be adjusted to show the actual height of the bottom of each gate above the intake invert.

Each gate shall stop automatically at the fully open position and shall close tightly without shock. The hoist is equipped with "S. K. F. 11 roller bearings, which are packed with ball-bearing grease. These pack ings normally will last many years; however, each bearing shall be checked once a year by pumping grease into each fitting, while the drain plug is removed, until the grease oozes out of the drain. Removal of the drain plug while pumping grease.prevents excessive pressures and injury to the grease seals. Ball-PeariQg~ of the hoist motors shall be checked every three months. The hoist motors shall· be lubricated_and maintained by qualified .electricians from the Maintenance Section. The hoist gears shall be lubricated with a light coating of gear grease; the wire-rope sheaves are self-lubricating.

d. Painting.-- Painting of exposed metal surfaces shall be done as required. Surfaces shall be thoroughly cleaned before painting;

oil and grease shall be removed with suitable solvents and clean cotton rags; and rust spots and loose paint, with stiff wire brushes.

Paint shall be applied in a workmanlike manner and in accordance with the applicable paragraphs of the original construction and supply specifications. Gates, gate frames, sheave blocks, trash racks, and other metal surfaces exposed to water shall be painted. Wire rope

. 16 sha 11 be treated thoroughly and often with · an approved. corrosion ·· resisting lubricant un.affected by temperature changes, to prevent rust.

34. Five-year i.nspection and maintenance. -- Five-year inspection and maintenance on tractor gates to be done by mechanics from-the Maintenance Section.

a. Remove .gate cover plates and raise gate by means of 11 UP-INSP 11 pushbutton. Inspect and clean tractor gates including roller chains and seals. ·

b. Loose, damaged, unserviceable or missing parts shall be tightened, repaired, or replaced in accordance with original contract specifications.

Electrical Facilities

35. ~lectric:al suppl~ and services.-- Ele~trical energy is supplied at 3-phase, ll ,500 vo ts, 60 cycle by the Southern Edison Company to a step-down transformer rack, near the downstream toe on the north west abutment of the· dam. Both 3-phase and single phase, nominal 440-volt, electrical services from the transformers pass through the meter box,' mounted on one of the transformer rack poles, and thence pass underground in the same trench through a 3-conductor No. 4 lead cable and a 2-conductor No. 2 lead cable in separate l~~inch rigid steel conduits. Both cables. continue underground to the crest of the dam, thence through two manholes along the crest, and thence under the service bridge to the switchboard in the control house.

{See drawings 436/4, 436/5, 436/6, 436/7, 436/36, 436/37, and 436/38 of Exhibit C.}

36. Standby power unit.-... The standby power unit consists of an alternating current generator, driven by a diesel engine. The .

generator supplies electrical energy for power and lights whenever power company service fails. A 6-cylinder International Diesel Engine, Mod. UD 236, drives a Palmer alternator rated at 30 K.W., 2400 R.P.M., 60 cycle at 480 volts. The standby power unit takes care of the connected load. A 300-gallon tank, under the service bridge near the control house, is filled and measured through either of two 9-inch hatch-covered handholes i.n the bridge floor.

The tank is vented into the open air under the bridge. An American Bosch EPS-B-30 Hydrotor is used to start the diesel· engine. (See Exhibit I.) .

37. Switchboard.-- A switchboard in the control house controls power and lighting circuits. Separate air circuit breakers control incoming power and light services from both the power company and the standby generator. Transfer switches permit selection of either source of energy for both power and lights.

38. Light fixtures.-- Light fixtures include two 1,500-watt floodlights on the upstream side of the control house tower, for lighting the trash racks; four 200-watt vaporproof lights under the control house floor, for lighting the access chambers; s·ix 300-watt lights in the cei'ling o.f the control house; and three recessed soffit lights above the doorway of the control house.

39. Convenience outlets.-- Convenience outlets consist of four outlets in the control house and two outlets in the access chambers under the floor of the control house. (See drawings 436/.37, and 436/38 of Exhibit C.)

40. Ground wire.-- The control house ground wire, a 4/0 copper cable, connects the switchboard ground bus to a 36-i nch square by ~-inch thi c.k

.copper grounding plate·, which is buried 8 feet deep in a salt-charcoal pit at the bottom of the .·reservoir a·nd about 160 feet upstream from the control house. ·

41. Operation of electrical facilities.-- Operation of the electrical facilities is described in detail in the following paragraphs. All references to exhibits refer to Exhibits I and J.