Between February and August Arizona Public Service (APS) and SWCA Environmental Consultants documented the hydroelectric complex, under guidance of the Historic American Engineering Record (HAER). Project managers Phil Smithers (APS) and Linda Martin (SWCA) coordinated historian Steely, photographer Jessica Maggio, and draftsman Hanson Todachine to complete the HAER documentation. Archives for the Childs-Irving Hydroelectric Project are at APS in Phoenix, Arizona. CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 2) Table of Contents Introduction......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 Physical Description of the 5 Layout of the 7 Description of the Engineering Aspects, Placed in an Engineering Context . . . . . . 8 9 Engineering Context 10 Dates of Construction and 13 Use and Operation (see also Maps and 13 History of the Resource, Placed in Historic 16 Contextual Franiework... ... . .. . . ... ... ... . .. 16 Significant Events and 16 Workforce Associated With the 18 Technology and 19 Summary 20 . . . . . . 22 Drawing "Water Conduit Childs & Irving Plants" . . . . . . . . . . . . 24 Drawing (one HAER site plan, Construction Drawings are in Field Records) Structures Within the Complex, AZ-65-A through AZ-65-FF, are in separate reports following page 24. CHILDS-IRVING HYDROELECTRIC PROJECT HAER No.
AZ-65 (Page 3) Introduction The term "unique" is carefully chosen in describing the Childs-Irving Hydroelectric Project. No other electric-generating system in the United States is known to exist in comparison to age, remoteness, simplicity and duration of operation.
In addition to its individual significance nationwide, the Childs-Irving Hydroelectric Project is a classic part of Arizona history spanning the century: remote low-grade mining operations sought reliable and less-expensive energy; a combination of investors, entrepreneurs and engineers modified a natural resource to supply the energy; cutting-edge technology entered a harsh and remote landscape; an isolated labor force merged experts with skills learned far away with local residents, including Native Americans with traditional ties to the land; growing cities soon offered an additional customer base; farmers and irrigation cooperatives became major consumers for their pumps and agricultural machinery; and distant metropolitan areas boomed by tapping the energy source.
Finally, a conservative operational approach to investment and maintenance retained aging technology within a huge modem power grid for many, many years past a reasonable retirement. Attention of engineering historians focused on the Childs-Irving plant as early as when the American Society of Mechanical Engineers named the facility their eleventh National Historic Mechanical Engineering Landmark (ASME) (Biddle In as part of a periodic federal operating-license-renewal procedure, owner Arizona Public' Service (APS) commissioned the successful nomination of Childs-Irving facilities to the National Register of Historic Places Consultants at Archeological Consulting Services, in Tempe, Arizona-led by Richard W. Effland, and Barbara S.
Macnider-completed the nomination and thoroughly described the plant in form, function and historic context (Effland and Macnider Much additional engineering detail was assembled in Childs/Irving Hydroelectric Decommissioning Project, Historic Properties Management Plan (Neal and Martin through sectional schematic drawings of the linear complex coupled with annotated aerial photographs, as well as site plans for the individual management complexes at Childs and Irving. Most information for the ASME, and designations and research projects came from the archives of Arizona Public Service, which holds a remarkable cache of material on Childs-Irving (unfortunately Irving construction documents are absent).
These documents-ranging from the correspondence and feasibility studies of original investors to subsequent operational and capital improvement records-have been saved and stored by APS. The company (in no longer employs a full-time archivist to manage these records and voluminous other files, but a secure and climate-controlled space is retained for the historical collection. Many current and retired APS employees CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 4) recognize the rich heritage of these records and information, as well as the profound significance of the Childs-Irving Hydroelectric Project itself Thus, Childs-Irving is already well documented and placed in historic context by indisputable authorities.
Regretfully, only the evaluated the project as a system totaling the sum of its components; the ASME designation (Biddle followed a very general analysis and the National Register nomination (Effland and Macnider considered significant only those components in place before major modifications beginning about The present HAER document's narrative and statistics draw from those efforts at their best, and also unfortunately from their limitations since the National Register nomination's "contributing" features dictated only those specific features (herein AZ-65-A through AZ-65-FF) to receive HAER-prescribed documentation.
Beyond those limitations, this HAER report organizes the ASME, and research in Historic American Engineering Record format and incorporates details from subsequent works, particularly the Fossil Creek Cultural Landscape Study by SWCA Environmental Consultants (Martin Headings and subheadings below follow the recommended organization of information in "Preparing the HAER Narrative" issued by the Historic American Engineering Record.
The power-generating facilities along Fossil Creek have functioned continually under a number of names since their conception in The founding Arizona Power Company (APCO) named its investment "Fossil Creek Water Power Project" in A year later the Electric Operating Construction Company called the first facility under construction "Arizona Power Company's Plant No. l." Shortly after completion this first powerhouse took the name "Childs" for bond-broker Childs of William P. Bonbright & Co. in Colorado Springs, New York, and London. Upon development of the second powerhouse below Fossil Creek dam, the company named it "Irving" for Irving Bonbright, a co-founder ofBonbright & Co.
The ASME designation of calls the combined plants "Childs-Irving Hydro-Electric Project" and the nomination of summarized a number of historic components as "Childs-Irving Hydroelectric Facilities." APS ultimately operated the system as "Childs-Irving Hydroelectric Project," the title used for the current description herein. With all its outstanding characteristics converging inevitably upon age, the Childs-Irving Hydroelectric Project nevertheless continued to operate efficiently as a 4.5-megawatt plant well into the century. Its removal from operation by Arizona Public Service, beginning in with decommissioning and remediation phased over a five-year period, was a decision based on issues other than economical operation.
In as part of APS' standard procedures, the utility company filed its application with the Federal Energy Regulatory Commission (FERC) to re-license the Childs-Irving Power Plant. However, when a coalition of community and environmental groups requested that APS analyze and consider decommissioning, CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 5) preliminary settlement negotiations were undertaken between APS, these interveners and interested parties. In after consideration and negotiation with environmental and community stakeholders, APS announced it had decided to decommission the Childs-Irving plant and restore full flow of Fossil Creek's waters to its stream bed.
APS felt that because of the stream's unique qualities, decommissioning the plant was a rare opportunity to return the area to its original condition. The benefits to the public associated with restoring this unique stream to its natural flowing state outweighed the business benefits the facility provided APS. (APS The decision by APS to decommission Childs-Irving led, among many steps, to a Section 106 review under the National Historic Preservation Act, and consultation with the State Historic Preservation Office (SHPO).
The Arizona SHPO stipulated, as part of mitigation for removing Childs-Irving from service and dismantling most of its facilities, that additional documentation be assembled to the standards of the Historic American Engineering Record, an external program of the National Park Service, U.S. Department of the Interior. HAER historian (based at NPS Intermountain Support Office, Denver) Lysa Wegman-French subsequently joined correspondence with Phil Smithers of APS and together they guided the HAER project to completion in SWCA Environmental Consultants-with James W. Steely as historian and project co-manager, Jessica Maggio as photographer, and Linda Martin as project co-manager-assembled the narrative and photographic record.
APS designer Hanson Todachine completed the project Cover Sheet to HAER standards. Physical Description of the Resource Fossil Springs and Fossil Creek take their names either from fossil-like travertine formations deposited by their mineral rich water, or from the presence of fossil impressions in their canyon's stone formations (Barnes The U.S.D.A. Forest Service's Rocky Mountain Research Station, Flagstaff Lab, maintains a Web site (Forest Service describing the anticipated closure of Childs-Irving Hydroelectric Project and restoration of Fossil Creek's natural flow.
Therein is a thorough description of geological conditions that form Fossil Springs and Fossil Creek canyon: Fossil Creek is representative of many of the drainages in the Transition Zone that begin at the Mogollon Rim Fossil Springs is located just below the edge of the Mogollon Rim, at the southern margin of the Colorado Plateau, in Fossil Creek Canyon. North of Fossil Springs the area is characterized by steep-walled canyons cut into flat-lying Paleozoic sedimentary rocks, while south of the springs the canyon is composed of Tertiary volcanic rocks [supporting the Childs- Irving facilities]. Approximately m of Paleozoic and Cenozoic strata are exposed within the canyon.
Paleozoic stratigraphy include[ s] the Mississippian Redwall Limestone, Pennsylvanian Naco Formation, Pennsylvanian/Permian Supai Formation, Permian Schnebly Hill Formation, Coconino Sandstone and CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 6) Permian Kaibab Formation South of Fossil Springs, the volcanic rocks, chiefly dark-gray basalt and yellowish-gray tuff, thicken abruptly to more than 600 m along an ancestral Mogollon Rim, where they were deposited in an ancestral lowlands. A basalt flow located approximately 400 m above the floor of the Fossil Creek Canyon produced a potassium-argon age of + giving a minimum age of formation of the ancestral Mogollon Rim.
A unique feature of the area is a prehistoric travertine deposit (Pleistocene and Holocene) that forms a conspicuous bench above Fossil Springs. Remnant travertine formations begin approximately 0.5 km below the springs and persist for approximately 7.5 km downstream. Due to diversion of spring water for power generation, modem travertine deposits in the natural channel only form where baseflow is returned to the natural channel. Presently, baseflow in the natural channel and subsequent downstream travertine deposition occur as a result of the Irving diversion dam leaking and at the Irving Plant tailrace, which discharges a small proportion during normal operations.
Areas of large travertine deposits similar to the historic Fossil Creek deposits are widely recognized as unique natural wonders. Discharge measurements taken on four occasions between June and July revealed flows that ranged from Usec to Lisee [averaging gallons per minute (Effland and Macnider Analyses of gauging data obtained at the Irving power station indicate that surface runoff contributes to the discharge less than 20 percent of the time. Effland and Macnider reported that a "wide diversity of plant communities within a relatively small area can be attributed to the permanent water supply and steep canyon slopes.
Fossil Creek is a relatively short watercourse and has a small drainage area." Vegetation along the Childs-Irving water diversion and facilities is dominated by mesquite and prickly pear cactus, with examples of catclaw acacia and pifion. Childs- Irving operating staff over many years were likely responsible for introducing interesting intrusions of fruit trees, cottonwood, and sycamore that thrived along the diverted watercourse (Martin CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 7) Fossil Springs prior to development. APS Photo Library #59 Layout of the Site Fossil Creek flows west then southwest from Fossil Springs with their total discharge of gallons per minute (43 cubic feet per second/cfs).
From the diversion dam and capture point just downstream of the springs, the Childs-Irving system begins with the controlled introduction of water into the flume system. Effland and Macnider 2) described the hydroelectric facilities as "two distinct flume systems and two hydroelectric generating plants with other related components." This was not quite the case historically, as the Childs plant diverted water from the same source--Fossil Springs-and the Irving plant had been planned from the beginning as a second integrated opportunity to tap sufficient water pressure at a shorter distance from the source.
Effland and Macnider summarized the two components and their relationship generally in consecutive order from the "capture point"-springs, dam and pond-to final use of the water at Childs powerhouse about 11 miles southwest: The facilities are located within the dissected canyon portion of Fossil Creek and range[] in elevation from [at Childs on the Verde River] to [at Fossil Creek dam] feet [S]teady ... water is supplied by a series of springs that have a constant flow and temperature. Since the area is so inaccessible, construction for all parts of the system, including the housing, has remained relatively simple. Although much of Irving and Childs [housing and support facilities] has changed CHILDS-lRVING HYDROELECTRIC PROJECT HAER No.
AZ-65 (Page 8) because of remodeling and rebuilding, the character of both settlements remains basically unchanged since their inception. The Irving system [of includes a metal flume, an inverted siphon, and a pressure pipe that conducts water from the capture point [Fossil Creek dam] down to the powerhouse, [a total ofJ approximately four miles.... The flume maintains a [descending, southwesterly] grade of 1 foot to feet although it traverses very steep slopes above Fossil Creek.... The plant together with housing, storage, and maintenance buildings sits on a broad, flat bench above Fossil Creek. To supply the Childs plant, water is transferred from the Irving plant into a reinforced concrete flume that sits on an artificial bench cut into the steep slopes.
The Childs flume originally consisted of concrete flume, wooden flume [replaced with steel], steel pipe, and concrete pipe There are seven tunnels and a relatively long, inverted siphon along the flume route The flume feeds a reservoir known as Stehr Lake that has a maximum capacity of 287 acre-feet of water. Two earth-fill[] dams at either end of the a [formerly] dry lake bed were used to create this storage reservoir. [Pressure pipe conducted] the water to Childs in its final descent. .. as water plunged approximately feet at a grade of feet.
Schematics of the entire complex layout are available in Childs/Irving Hydroelectric Decommissioning Project, Historic Properties Management Plan through sectional schematic drawings of the linear complex coupled with annotated aerial photographs, as well as site plans for the individual management complexes at Childs and Irving. (Neal and Martin Description of the Engineering Aspects, Placed in an Engineering Context The Childs-Irving project is a "uniquely engineered hydroelectric system in terms of construction and operation," in the assessment of Effland and Macnider 8/1 ).
It achieved an unusually strong static head pressure through "the high degree of topographic relief that allows for a drop of 1 foot per feet over a distance of only miles," creating a static head of 480 feet at Irving-sufficient for one low-pressure generator-and feet at Childs-sufficient for three high-pressure generators. The Childs system particularly, noted Effland and Macnider "is recognized for its simplicity in design" through three engineered components in sequence from the water source: the steel and reinforced concrete flume, pipes, and tunnels; the intermediate reservoir; and the durable mile-long conduit of concrete and steel between the reservoir and the Childs powerhouse.
The use of the concrete flume in the Childs system was required because the terrain and ground conditions precluded the construction of a wood and ditch-type CHILDS-IRYING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 9) flume conduit. When the flume was operational, there was a marked [and unexpected] reduction in friction created by using the smoothed concrete. The system was more efficient than the ordinary ditch or wooden flume that was extensively used in the western United States [Stehr Lake] reservoir could store enough water to run the Childs plant for three and one-half days at the average steady flow of the stream.
This meant that the flume and other components located above the reservoir could be overhauled or cleaned without interrupting the normal operation of the plant Finally, the system from Stehr Lake to the [Childs] headworks is remarkabl[y] well protected with a series of tunnels and pipes. For approximately feet, the water is conducted through a concrete-lined tunnel and both reinforced concrete and steel pipe. (Effland and Macnider See individual-structure HAER reports for detailed descriptions of AZ-65-A through AZ- and their specific engineering aspects as structures within the Childs-Irving Hydroelectric Project complex.
See also Childs/Irving Hydroelectric Decommissioning Project, Historic Properties Management Plan Neal and Martin for schematics that place all components into their water-flow-system engineering context. Glossary adit - shaft constructed for access to a tunnel for construction, repair, ventilation, and/or drainage. baseflow - calculated average flow of water based on records oflow and high ranges. bridge- engineering assembly of wood, metal or concrete to convey vehicles and/or linear structures (such as pipe and flume) across a considerable depth and/or clear-span width (see trestle). dissected canyon - landscape eroded into hills, valleys and/or canyons.
flume - continuous semi-circular trough, of wood, metal or concrete, to convey water from its source to its applied use; usually engineered to drop at a constant rate for consistent water flow and pressure. forebay- a structure than consolidates, controls, and directs water from one feature, especially a flume, entering another structure such as a sluice gate, tunnel or siphon. grizzly - evenly placed and rigid bars of iron or steel across a water intake to trap floating debris and prevent large objects from entering a flume, pipe, tunnel, etc. penstock- circular pipe, usually of high-strength steel, to convey water at a greater drop and shorter distance than the flume, creating greater pressure at its discharge.
siphon - sealed pipe to convey flume water across an obstacle too large or long for the expense of a conventional bridge or trestle; water drops into the siphon intake under gravity, and rises to the siphon discharge under atmospheric pressure to the same level as the entry, or in the case of a flume system, to a level slightly lower that its entry to maintain consistent water flow and pressure. CHILDS-IRYING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 10) sluice - artificial channel for water, such as a flume, that controls its flow.
stand pipe - circular, vertical open pipe or tank standing above the junction of one conveyance into another, that normally allows water to pass through the junction, usually under some pressure; if entering or exiting flow is interrupted or creates a pressure surge, water in the standpipe drops slightly or backs up into its additional capacity to prevent loss of pressure in, or entry of air into, the system. surge tank - see stand pipe. tailrace - channel for water movement through a fixed, usually cast-concrete, structure, especially in the foundation of powerhouses to move water into and out of water wheels for power generation and then discharge.
trestle - series of piers or groups of pilings--ofwood, metal or concrete-that convey a linear structure usually across a shallow depth without the expense of a clear-span bridge; sometimes used in combination with a bridge as its flanking approaches. Engineering Context Engineer Raymond Masson's innovative design of the Childs powerhouse eliminated unreliable automatic switching in favor of manual routing of electrical loads. "If one circuit was to fail," analyzed Eflland and Macnider, "the load could be diverted to a load tank, a tank filled with brine water, and subsequently, manually rerouted at the master plant to a second transmission line circuit. This ...
simply required an operator at Childs to monitor an ammeter that would record any short-circuit problems along either line." The innovative transmission system at Childs meant that the service was more reliable than that from any other hydroelectric plants in the western United States. The transmission line plan devised for the Childs plant was adapted at other hydroelectric plants in the southern California area in subsequent years.
The concrete flume, the reservoir, the transmission line network, and other elements at the Child[s]-Irving Hydroelectric Facilities, make the system not only efficient and reliable but also wonderfully simple in design (Eflland and Macnider Arizona Public Service offered public descriptions of the two power plants on its Web site (APS Variations in distances and other measurements between these modem descriptions and statistics used in the National Register nomination are likely explained through adjustments between more intuitive records (used in the document) and more exact statistics assembled in recent years by APS.
Irving Hydroelectric Power Plant The Irving Development includes a diversion dam in Fossil Creek; a conduit about 3 1/2 miles long; a surge tank; a penstock feet long]; a powerhouse on Fossil Creek containing a 2,100-horsepower turbine connected to a kilowatt generator; a tailrace discharging into the forebay of the Childs Flume; a step-up substation; a 69 kilovolt transmission line about 6.6 miles long, extending CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 11) from the step-up substation to a switchyard; access roads; and appurtenant facilities.
Childs Hydroelectric Power Plant The Childs Development includes a diversion dam in Fossil Creek just below the Irving plant to divert the water of Fossil Creek into the forebay of the Childs flume; a forebay; a conduit about 4 1/2 miles long; a regulating reservoir known as Stehr Lake; a pressure tunnel about feet long; a concrete pipe about feet long; a concrete surge tank; a penstock about feet long; a powerhouse on the Verde River containing three 3,000-horsepower water wheels each connected to an 1,800-kilowatt generator; a short tailrace; a step-up substation; two 69 kilovolt transmission lines about 200 feet long, extending from the step-up substation to a switchyard; access roads; and appurtenant facilities.
"Transmission lines" noted in these descriptions are now all carried by galvanized steel lattice structures dating from about with at least one original "windmill" tower surviving at the Childs powerhouse. The original prefabricated steel windmill towers, chosen over typical wood transmission poles, allowed quick delivery by railroad of an off-the-shelf industrial product that could be brought to the field in small pieces and assembled into a strong and stable elevated platform on site.
The 700 steel lattice towers acquired for the first transmission line each weighed pounds and came in pieces small enough for men at the railhead to load and unload them easily from wagons and the backs of pack mules (Effland and Macnider By contrast, wood poles also would have ~een hauled long distances and would have been more difficult to install deeper in rocky soil with the tools and technology of the early Mule train - APS Photo Library CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 12) "Access roads" include the connecting roads between facilities-PS FS and Flume Road---0riginally built by Arizona Power Company as part of its ambitious project. The U.S.D.A.
Forest Service now maintains FS traversing the property generally east to west from near Camp Verde to near Strawberry, and FS 502 connecting southwest to Childs. "Appurtenant facilities" include telephone lines connecting Childs and Irving with distant APS offices and commercial service, as well as offices, housing, shops, garages and other necessities of remote operations. For the hydroelectric system proper-excluding outbound power lines, access roads and ancillary facilities-Childs-Irving is composed of a large variety of engineering aspects, or features, shaped from a variety of industrial materials.
Concrete examples: feet of wire-mesh reinforced concrete on concrete flume bench, produced from sections pre-cast near the work site; feet of concrete-lined tunnel, 6 feet high and 3.5 feet wide cutting through Ike's Backbone ridge; feet ofreinforced concrete pipe pre-cast on site; Childs and Irving powerhouses, and associated tailraces in their foundations. Metal (assumed to be primarily steel) examples: transmission towers, at least 700 modified from windmill tower designs; pipe sections of riveted steel and welded, riveted produced by Pelton Water Wheel Company of Harrisburg, PA, and welded produced by Krupp in Germany; siphon pipes; trestles across canyons and washes; steel roof trusses, and corrugated roofing of the Childs Powerhouse.
Wood examples: originally supported metal-conduit flumes; maintenance platforms along metal and concrete flumes; original formwork for pre-cast and cast-in-place concrete pours; telephone and transmission-line poles. CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 13) Dates of Construction and Changes Construction began on the initial project phase-road, telephone lines, Fossil Creek dam, water control system to the Verde River, "Childs" powerhouse, and transmission lines- in April Operators in the Childs powerhouse placed their first generator online on 18 June Childs powerhouse under construction.
APS Photo Library Expansion of the successful system began with construction on the "Irving" system- water system from Fossil Creek dam, powerhouse, operators' camp, and transmission lines-in May Its single generator joined the Fossil Creek grid on 25 April By TAPCO invested in several major improvements to the system, including considerable concrete and steel work for realignment of the Sally May/Purple Mountain siphon. Over the years of operation, most wooden structural members were replaced with steel, and many concrete flume components in vulnerable locations were replaced with steel flume sections.
Electrical switching and distribution components have been replaced regularly, so that by the early new control cabinets occupied both the Childs and Irving Powerhouses, and new steel and wood-pole towers replaced most of the original transmission lines spanning from the Fossil Creek system. (Effland and Macnider Use and Operation (see also Maps, Drawings, and individual component descriptions) In their description of the engineering aspects of Childs-Irving, Effland and Macnider drew from several sources: a U.S.D.A. Forest Service report on Irving, a set of drawings of the hydroelectric operation, a inventory of facilities upon the reorganization of Arizona Public Service and its last major Childs- Irving facility upgrades, and interviews with veteran operating personnel.
Following is a summary of components/features at Childs-Irving, based on the Effland and Macnider synthesis. Their description number is paired with the CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 14) corresponding HAER complex-structure letter (e.g. AZ-65-A through AZ-65-FF), in sequential component-order tracking spring water downstream through the system in distances of feet advanced by each feature. Note that Effland and Macnider's length figures do not consistently match the complex-structure inventory, and considerable lengths of flume-plus modified, more recent, and ancillary facilities--did not receive and/or HAER designations for further engineering and historical evaluation.
Irving System: HAER Component/Feature Distance 1 A Capture point (Springs Pond and Dam) 0 2 Automatic cleaner 3 B Intake system 4 Steel flume on stringers and bents feet 5 c Flume tunnel # 1 115 feet 6-8 Steel flume on stringers and bents feet 9 D Inverted siphon 434 feet Steel flume on stringers and bents feet 10 Steel flume on bridge(# 1) feet Steel flume on stringers and bents feet 11 Steel flume on bridge (# 2) feet Steel flume on stringers and bents feet 12 Steel flume on bridge (# 3) feet Steel flume on trestles and bents feet Steel flume on bridge feet Steel flume on stringers and bents feet 13 E Sand box (surge box) 8.0 feet 14 F Irving penstock pipe feet 15 G Powerhouse and pipe feet 16 Transformers 17a Office and Storage Building 17b H Storehouse and Cottage TOTAL feet Inside the Irving powerhouse, water under 470 pounds-per-square-foot of pressure turned the single Allis-Chalmers Francis-type water wheel, connected by a shaft to the General Electric generator, producing kilowatts of power.
Water then flowed through the tailrace in the powerhouse's concrete floor into an open concrete tailrace outside the powerhouse a short distance into the rock cut leading to the Childs flume. See Use and Operation explanation at AZ-65-G component forms for additional information. CHILDS-IRVING HYDROELECTRIC PROJECT HAER No.
AZ-65 (Page 15) Childs System (after managed from the end of Irving System): HAER Component/Feature Distance Discharge from Irving Powerhouse 0 18 I Rock cut, flume intake, forebay and sand box 390 feet 19 J Concrete flume on bench feet 20 Rock shed Wooden flume on trestle feet 21 Steel pipe bridge(# 1) feet 22 K Flume tunnel # 1 feet Concrete flume on bench feet 23 L Flume tunnel # 2 feet Concrete flume on bench feet 24 M Sally May/Purple Mountain siphon intake 25 N Sally May/Purple Mountain steel siphon pipe feet 26 0 Steel flume on bridge(# 2) feet 27 p Flume bridge(# 3) 28 Q Flume bridge (# 4) 29 R Sally May/Purple Mountain siphon discharge 30 s Steel flume on trestles 31 T Flume tunnel # 3 feet 32 u Concrete flume on bench and bridge(# 5) feet 33 v Flume tunnel # 4 feet 34 Concrete flume on bench feet 35 w Flume tunnel# 5 (under FS 502 road) feet Concrete flume on bench and bridge feet 36 x Flume tunnel # 6 feet 37 Wood flume bridge(# 6) feet 38 y Stehr Lake and dam feet At Stehr Lake, the 27.5-acre, 13.3-foot deep reservoir stored enough water to charge the Childs turbines for about three days if Fossil Creek flow interrupted upstream.
39 z Pressure tunnel intake 40 AA Flume (pressure) tunnel # 7 feet 41 BB Concrete intermediate pipe feet 42 cc Stand pipe/surge tank Here the 36-feet-high, 30-feet-diamater concrete standpipe serves as junction between the 1: 1000-fall flume components and the penstock pressure pipe, temporarily holding water flow from Stehr Lake if the Childs turbine valves were closed. 43 DD Penstock pipe into plant feet 44 EE Childs Powerhouse 45 Childs substation/transformers CHILDS-IRVING HYDROELECTRIC PROJECT HAER No.
AZ-65 (Page 16) 46 FF Office 47 Machinist shop TOTAL feet Inside the Childs powerhouse, water under pounds-per-square-foot of pressure flowed into three branch pipes to rotate three Pelton-type water wheels, each direct- connected by a shaft to one of three General Electric generators, each producing kilowatts of power. In new transformers at Childs boosted the powerhouse capacity to kilowatts. Water then flowed through three tailraces in the powerhouse's concrete floor into open concrete tailraces outside the powerhouse a short distance into the Verde River. See Use and Operation explanation at AZ-65-EE component forms for additional information. History of the Resource, Placed in Historic Context Contextual Framework Western-state land and water surveys from the by the U.S.
Department of the Interior's Geological Survey (U.S.G.S.) brought attention and instruction for the region's development through water utilization and technology (Gilpin, et al. This critical government data served a myriad of public purposes, from identifying immediate homestead opportunities to speculating on vast homestead expansion through development of dams and irrigation systems in certain desert basins. Private mining companies and associated entrepreneurs-railroads, suppliers, fuel brokers-likewise used U.S.G.S. maps and data to calculate the feasibility to extract, process and ship ores from known and speculated deposits throughout the same region.
One approach common to both government and mining speculation was the use of professional engineers, many trained in urban Eastern universities then assigned to comparative Western wilderness, to project technological solutions upon the natural landscape. Significant Events and Individuals While American ranchers in the Verde River Valley are credited with "discovering" this natural water source in the Native American relations with Fossil Springs, Creek, and Canyon extend far back through unrecorded time as places of tradition and cultural meaning.
As the most popular story goes, in local rancher Lew Turner, thinking not as a native or cattleman in the steep canyon but amazingly like a hydroelectric engineer, realized that struggling mines to the west in the Bradshaw Mountains and Black Hills offered a ready market for electricity generated from the fortunate conditions of water and gravity at Fossil Creek (APS In Turner assembled associates including Iva Tutt, a genuine electrical engineer from Long Beach, California, to form the Arizona Power Company (APCO).
Tutt proved adept on political turf, achieving territorial tax abatement for the enterprise, and hydroelectric design, working out the basic framework of a diversion system along Fossil Creek canyon and the Verde River (Effland and Macnider CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 17) APCO's Turner and Tutt could not raise adequate capital, however, so in fellow APCO investor and project chief engineer Raymond S. Masson took over the enterprise. Masson and his partner at Electric Operating Construction Company, Francis S. Viele (also probably an engineer), reorganized the company as The Arizona Power Company (T APCO). They introduced to the project their strong-and perhaps surreptitious- relationship with the General Electric Company of New York and its president W.A.
Coffin. Good timing for the mining industry and Coffin's support brought adequate investments of million through bonds sold by William P. Bonbright & Company and its representative Childs. As noted in the Introduction, the first powerhouse took its name "Childs" from the Bonbright company's bond-broker; upon development of the second powerhouse in the company named it "Irving" for Irving Bonbright, a co- founder ofBonbright & Co. (Effland and Macnider Masson Part of Tutt's and/or Masson's design called for a reservoir to store a backup supply of Fossil Creek water a relatively short distance above the first-constructed powerhouse on the Verde River.
In the further tradition of naming major construction features for the investors, engineers designated the reservoir Stehr Lake, in honor ofF.W. Stehr, a partner of William Bonbright's in Colorado gold mine ventures (Holabird The project signed its first contract with the United Verde (UV) Mine at Jerome on 19 March The substantial UV mine operation and its local rivals resulted from copper magnates of Montana and Phelps Dodge competing ferociously over known and suspected copper deposits in the area. Masson and Viele used their Electric Operating Construction Company as general contractor and assembled specifications and equipment that would meet the UV Mine's horsepower maximum load plus additional power for other customers.
By April construction began on the essential road from the nearest rail siding at Mayer 40 miles to the west, joining the Verde River west of Childs (later replaced by present FS 708 from Camp Verde). Following an astonishing pace considering the remote landscape, on 18 June the project's first generator energized the approximately 60-miles oflines to Jerome and its nearby UV Mine. Other mines along the initial transmission line-running westerly across the Black Hills to Poland, thence splitting to supply Prescott to the northwest and Jerome to the north- bought power as well.
By TAPCO added a separate 39-mile line along the Verde River to supply Jerome directly (Effland and Macnider Electricity freed these mining operations from steam-powered machinery running on expensive coal and oil shipped to their sites by umbilical and monopolizing rail lines. This new, more reliable, and highly competitive power source also "enabled the mining industry," noted Effland and Macnider "to expand in several directions," including new air compressors for equipment in the mine shafts, electric trams to haul ore from the mines, plus smelters and stamp mills to "process larger amounts of ore more efficiently." Outbreak of the World War in among European nations caused copper and other raw metal prices to rise appreciably, and TAPCO's customer base grew accordingly.
In CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 18) addition, in the owners of the UV mine "struck a vein of copper 5 feet thick," according to Arizona historian Marshall Trimble "the richest ever found in American copper mining." Construction of the planned second powerhouse, and a daring new flume system beginning at Fossil Springs dam, commenced in May The resulting facility housed only one low-pressure generator but added another horsepower and kilowatts to the system. Satisfaction of wartime energy demands and accelerated development in the Verde, Agua Fria, and Hassayampa River Valleys followed these key technological achievements.
In T APCO calculated that the Childs-Irving hydroelectric system approached its maximum capacity, and constructed its third powerhouse in Clarkdale as a steam- powered plant close to several mine customers. The plant opened that September and doubled TAPCO's total power output. For decades TAPCO faced little power generation competition in its huge service region of Yavapai, Gila and Coconino counties. Through the Second World War, only the U.S. Bureau of Reclamation's Salt River Project and California's Pacific Gas & Electric served Phoenix and Maricopa County to the south; local companies served the railroad outposts of Seligman, Ash Fork, and Flagstaff to the north (Effland and Macnider EPRI Journal The substantial Roosevelt Dam electrical generators of the U.S.
Bureau of Reclamation provided little electricity during a drought that settled in the Salt River basin by the late In the City of Phoenix and its other major electrical provider, Pacific Gas & Electric (through its subsidiary Central Arizona Light and Power Company, CALAPCO), purchased additional wattage from TAPCO via a new 75-mile line to Phoenix from Sycamore Substation 16 miles west of Childs. TAPCO acquired the Seligman and Ash Fork suppliers in and extended transmission lines to their grids. By TAPCO also sold excess power to the local Wickenburg and Flagstaff systems. CALAPCO purchased T APCO in followed by major upgrades to the Childs-Irving system and transmission lines. In CALAPCO merged with Arizona Edison Company to form Arizona Public Service, APS.
(Effland and Macnider Workforce Associated With the Resource For its first power plant on the Verde River, Electric Operating Construction Company commissioned as many as 450 men and 450 draft animals to build the road, transport equipment from the railhead, and construct the water diversion and (Childs) powerhouse. Teamsters who hauled over the road needed five to six days-in good weather-to complete a one-way haul, so the company established several overnight boarding houses at ranches en route (APS A commissary at Childs warehoused food and supplies for five work camps at West Portal, Stehr, Purple Mountain, Sally May and Hynes.
"The workers included both Mexicans and Indians," Effland and Macnider wrote, "but records do not show the relative proportions of each." CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 19) "The main labor force, 600 [sic] men," according to Fossil Creek Cultural Landscape Study (Martin "was drawn from local Yavapai and Apache groups." These indigenous tribe members had been forced from the same land in 1875-little more than a generation earlier-southeast to the San Carlos Reservation on the Gila River. After and eventual establishment of reservations in the Verde Valley, Yavapai and Apache returned to the area to find that Anglos had claimed much of the land.
Ironically, through employment in and by TAPCO and the Electric Operating Construction Company for road building and power system construction along Fossil Creek, Yavapai and Apache received subsistence wages and, most importantly for future generations, renewed contact with their ancestral landscape. (Martin Neal and Martin Technology and Labor Initial construction tasks of and kept between 300 and 450-some sources, above, list 600-men employed at Fossil Creek and along the road to the railhead at Mayer. While the horse, mule, and human enrollments are impressive, this labor- intensive endeavor also brought state-of-the-art technology to the wilderness.
Concrete mixers on wagon beds produced tons of material for the Fossil Springs dam, flumes, foundations, powerhouse walls and other details. The special-order steel penstock pipe from Germany required pipe-joining equipment, technology in its infancy at the pre- World War I construction along Fossil Creek. The 700 steel lattice towers acquired for the first transmission line each weighed pounds and came in pieces small enough for men to load and unload them easily from wagons and the backs of pack mules. (Effland and Macnider Alston CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 20) Once construction transitioned to operation, talented construction worker-perhaps scores-stayed on to manage the power plants and transmission lines.
As the facility adjusted to its most efficient operation and electrical switching and transmitting equipment improved tremendously over the years, the Childs-Irving Hydroelectric Project settled into a workforce of nine employees by Of those on the 24-hour- per-day, seven-day-per-week schedule, several were multi-generational Childs-Irving employees and at least four descended from common Childs-Irving career families. Summary In February the Yavapai Magazine og>rescott described the importance of electricity to the region's rapid growth and strong economy just before the United States entered the World War in April: It is hard to realize the full importance of "electric juice" in the developing of Yavapai [C]ounty's mines.
The price charged has resulted in a saving of 30 to 50 per cent to consumers as compared with other means of power generation. In many cases it has supplied power easily, where the condition of roads and the country would practically prohibit the transportation of fuel.
(Effland and Macnider In Childs-Irving's 3.5 megawatt plant produced electricity for $18 per megawatt hour compared to $8 to $9 from large hydroelectric dams, $15 from Arizona's single nuclear power plant, $15 to $25 from coal-fired units, $20 from small solar facilities, and $30 MWh from most natural gas-fired plants (Alston In a historic summary of his success with the Childs-Irving Hydroelectric Project, chief engineer and planner Masson wrote after its completion: The location of two plants in this desolate area demanded many innovations in design, transportation and construction. Among these were steel transmission towers, forged penstocks and the handling of every component by mule teams. Electrical energy was essential to the exploitation of the region's rich copper deposits.
(from Biddle The Childs and Irving powerhouses and their energizing water system were constructed with great effort in an extremely remote landscape. Engineers and laborers of the Childs- Irving system captured a natural water source and followed dramatic topography for construction, operation and maintenance. Once operators learned to stabilize the system, the Childs-Irving Hydroelectric Project generated electric power in a remarkably simple and efficient manner, continuously for 95 years. 0 CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 21) Above - steel pipe on wagons. APS Photo Library #65 Right - making concrete pipe. APS Photo Library CHILDS-IRVING HYDROELECTRIC PROJECT HAER No.
AZ-65 (Page 22) Bibliography Advisory Council on Historic Preservation (ACHP) "Arizona: Surrender of the Childs Irving Hydroelectric Project License, Yavapai and Gila Counties." Electronic document: www.achp.gov. Accessed 5 August Alston, Elmer Personal conversation with James W. Steely. Alston is a 21-year APS veteran and 20-year operator at Childs and Irving Powerhouses. 22 October Arizona Public Service (APS) Archives Historic photograph collection. Historic drawings collection. Historic documents collection. Available through appointment at: APS, P.O. Box Phoenix, Arizona Arizona Public Service (APS) Childs-Irving: A History. Brochure. Relates to Effland and Macnider Arizona Public Service (APS) Childs-Irving Hydroelectric Project Homepage.
Electronic document, Accessed 8 July Biddle, Walter A. "Childs-Irving Hydroelectric Project-1909/1916." Documentation for dedication of Childs-Irving Hydroelectric Project as a National Historic Mechanical Engineering Landmark. Designated 10 April Biddle was then chairman of the ASME History & Heritage Committee. Barnes, Will C. Arizona Place Names. The University of Arizona Press. Tucson. Originally published Byrkit, James W. "A Log of the Verde, the "Taming" of an Arizona River. In Water in a Thirsty Land, Sonoran Desert and Mountain River History. Pifi.on Press Reprinted from The Journal ofArizona History, Effland, Richard W., and Barbara S. Macnider Childs-Irving Hydroelectric Facilities. National Register of Historic Places Registration Form. U.S.
Department of the Interior, National Park Service. Washington, CHILDS-IRVING HYDROELECTRIC PROJECT HAER No. AZ-65 (Page 23) EPRI Journal "Creating the Electric Age." Electric Power Research Institute. Palo Alto California. March Forest Service, USDA "Fossil Creek." Electronic document. Accessed 9 July Rocky Mountain Research Station. Northern Arizona University and U.S.D.A. Forest Service. Flagstaff. Gilpin, Dennis and James Steely, with Jean Ballagh, Neal, Dan Newsome, Michael O'Hara, Gordon Rakita, and Louise Senior Water Utilization and Technology in Arizona's Historic Era, Statewide Historic Context on Multiple Property Documentation Form for National Register of Historic Places.
SWCA Environmental Consultants for Arizona State Historic Preservation Office and USDI Bureau of Reclamation. Phoenix. Hay, Duncan Hydroelectric Development in the United States, Edison Electric Institute. Washington, Holabird, Fred, Americana Electronic document: Accessed 4 August Martin, Linda Fossil Creek Cultural Landscape Study. Commissioned by Coconino National Forest. SWCA Environmental Consultants. Flagstaff. Masson, Raymond S. Letter to Childs, New York. The Arizona Power Company letterhead. One of a number of descriptive letters from Masson in APS archives. Neal, and Linda Martin Childs/Irving Hydroelectric Decommissioning Project, Historic Properties Management Plan Prepared for APS/Generation Engineering. SWCA Environmental Consultants. Flagstaff.
Trimble, Marshall Arizona: A Panoramic History ofA Frontier State. Doubleday & Company, Inc. Garden City, New York. tJ ~ (IQ = -~ie. ~ ~ ('D ""! 1..J...,li.tJ TO llfVIN N. LilNdrH n 0 TOTl'll- TH WATl:R CONDUIT 11.fO.S.-f't'I TUIM'AL.s n F&U~S 11n Lwc e: a.~111 CN1t..IJ$ ~ 1a.2' JI/../'" ~., CIJ XltVING- i ~11r.o' .l!I ,. ... ~ z .2' ~Ro - r= o~ - Cf> n ::i:: < "ti ,. IH' '!a'i .u. G') I cn -B Cll I -< :; a - :0 \0 ow ~ m- r m (") ~ -I ~'' :0 0 ~ -0 ~ :0 0 0 tI1 m (") 'oo'-~")( 1 -I ~ f$ x IY.c 11' .- )( ~ I NOTE: )> THI# IHIAWI,,. 6LIVA1'iON4 COlllll!CT AS OF S-15-S<I. ~~ 1< ~ m ~ :0 -#".II rtM ~~ 1' '. x ~ z i1'.r JC y"' CJ -.I' .. .it ~ .-;a ?z "ti )> ~ii x """ H'rlHtA~LIC OONWIT -.u X 4i'B'. lllOW/W. Tt:IV //IND l'-~IM"l"tott# N !)) (IQ ~ 0 8 1' - 2" .\ I 1...ze -u ;-.
w C1l (1) tI1 No. Q TOTAL-~' ~ O'I ~ '-' VI
Block