SECTION 3 OVERHEAD TRANSMISSION ALTERNATIVES 3-1 SECTION 4

City of University Park, Texas - i - Sega Project No. 06-0069 138-kV Underground Transmission Feasibility Study

TABLE OF CONTENTS Page No. SECTION 1 INTRODUCTION 1-1 SECTION 2 EXECUTIVE SUMMARY 2-1 SECTION 3 OVERHEAD TRANSMISSION ALTERNATIVES 3-1 SECTION 4 UNDERGROUND TRANSMISSION ROUTES 4-1 SECTION 5 CONVERSION OF ALLEY AERIAL SERVICES TO UNDERGROUND 5-1 SECTION 6 CONCLUSIONS 6-1

SECTION 1

INTRODUCTION

City of University Park, Texas 1 - 1 Sega Project No. 06-0069 138-kV Underground Transmission Feasibility Study

INTRODUCTION

The City of University Park, Texas has contracted with Sega Inc. to provide a feasibility study for

undergrounding an existing aerial 138-kV transmission line and for undergrounding all existing aerial

utility lines. Various alternatives for replacing the line with new overhead construction as well as

installing the transmission line underground are considered.

The Sega project team met with City staff, representatives of the various entities responsible for the

affected utilities, and representatives of the Transmission Line Steering Committee in March 2006. After

discussions, this Study was developed taking into consideration input from the interested parties and the

various alternatives; then, preliminary opinions of probable cost were developed. A draft study was

prepared sent to the City for review and a discussion was held in May 2006 with City Council members,

City staff, and members of the Transmission Line Steering Committee. The Sega project team includes

utilizing the services of Power Delivery Consultants, Inc. for the underground transmission considerations

due to the highly-specialized nature of underground high-voltage systems.

This Study is intended to provide the City of University Park, Texas and the Steering Committee

information to assist in determining the alternative that fits their needs for the transmission line

replacement.

SECTION 2

EXECUTIVE SUMMARY


EXECUTIVE SUMMARY This Study includes three primary sections which include determining various alternatives and opinions

of probable costs for replacing the existing Greenville - Loma Alto 138-kV transmission line with

overhead construction, placing the 138-kV transmission line underground, and placing existing overhead

electric distribution, cable TV, and telephone utilities underground along the transmission line route. The

resulting alternatives and opinions of probable costs are tabulated at the end of this summary.

The overhead transmission alternatives include replacing the transmission line with new equipment and

materials using the existing design, replacing the line with skip-span construction, replacing the line pole

for pole (two alternatives with different conductor spacing, shorter spans, and shorter poles), and

replacing the line without underbuilt electric distribution, cable TV, and telephone wires. Opinions of

probable costs are developed .

The underground transmission briefly describes the various types of underground transmission circuits,

selects the most desirable for this application, and develops opinions of probable cost for construction.

Two alternative routes are considered: Placing the line under the alley and routing it in one of the

adjacent streets. Opinions of probable costs were developed for these alternatives.

The third primary section of the Study concerns the conversion of alley aerial services to underground.

Two variations of this conversion are shown. The first places the electric distribution, cable TV, and

telephone underground in the alleys along the transmission line route. This alternative was considered to

be constructed in conjunction with the City rebuilding/replacing the sanitary sewer, water lines, and the

existing gas lines. Additional rights-of-way and easements would need to be obtained. A variation of this

places the electric distribution, cable TV, and telephone service feeds at the front of the residential lots to

avoid obtaining backyard rights-of-way which would be very difficult. This would actually require,

possibly, more rights-of-way than the alley construction, but would generally be in less congested (but

more visible) areas. Opinions of probable costs were developed for the undergrounding construction as

well as obtaining rights-of-way.

Table 6-1 is as included in the Section 6 - Conclusion. It summarizes the various combinations of

alternatives ranging form rebuilding the existing 138-kV transmission line to placing all utilities

(transmission, distribution, cable TV, and telephone) underground.

Table 6-1Summary of Alternative Transmission and Distribution Options

Overhead Underground Obtain ROWOverhead Distribution Underground Distribution for Total

Transmission & Telecommunications Transmission & Telecommunications Underground Cost

Rebuild Line, Existing Configuration;Pole-for-Pole;125' Spans +/-

52' - 57' Above Ground

TransferExisting None None None

$4,499,800Rebuild Line, Vertical

Configuration;Skip-Span Construction;

250-Spans +/-;68' Above Ground


$3,552,284

Rebuild Line, Vertical Configuration;Pole-for-Pole;125' Spans +/-

63' Above Ground


$4,620,000

Rebuild Line, Delta Configuration;

Skip-Span Construction;250-Spans +/-;

61' Above Ground


$3,575,000

Rebuild Line, Vertical Configuration;250' Spans +/-;No Underbuilds;

50' Above Ground

Remove None PlaceUnderground in Alley Obtain ROW

$8,329,950 $6,036,000 $17,430,950Rebuild Line, Vertical

Configuration;250' Spans +/-;No Underbuilds;

50' Above Ground

Remove None Place Underground in Front of Lots Obtain ROW

$9,000,000 $12,830,000 $24,206,596

Remove Transmission;Leave Distribution

and Telecom

Leave in Place;Cut Tops off Poles;34' Above Ground

Install UndergroundTransmission None None

$11,800,000 $12,069,438

Remove Remove Install UndergroundTransmission

PlaceUnderground in Alley Obtain ROW

$11,800,000 $8,329,950 $6,036,000 $26,613,775


Place Underground in Front of Lots Obtain ROW

$11,800,000 $9,000,000 $12,830,000 $34,667,000

Alternative 7A$1,037,000

Alternative 1

$4,499,800

Alternative 4

$3,575,000

$3,552,284

Alternative 7

Alternative 2

Alternative 3

$447,825

$4,620,000

$2,376,596

Alternative 5

Alternative 6

Alternative 5A

$3,065,000

$269,438

SECTION 3

OVERHEAD TRANSMISSION ALTERNATIVES


OVERHEAD TRANSMISSION ALTERNATIVES TXU Delivery (TXU) owns a 138-kV transmission line which passes through University Park, Texas.

The line interconnects the TXU Greenville Substation located southeast of University Park with the Loma

Alto Substation located southwest of University Park. The majority of the line passes through University

Park alleys. The line is constructed on wood poles. In addition to the transmission circuit, the poles also

carry a three-phase distribution primary circuit, single-phase secondaries, and telephone and CATV

circuits. Span lengths average 138 feet.

TXU intended to upgrade the line in such a manner that would result in taller poles, as discussed below.

However, the public has expressed that taller poles are not acceptable and has expressed a desire that the

transmission line be placed underground. Further, a University Park master plan from 1989 set out a

program of City-wide alley improvements that would place all overhead utilities underground. While the

City has undertaken alley improvements under a “mile-a-year” program, those improvements have been

limited to replacing underground pipes (water, sewer, and gas) and paving, but not overhead utilities. It is

not clear if the master plan intended for the transmission line to be placed underground. Underground

transmission is rarely constructed because of the high costs, whereas distribution lines and

communication lines are routinely undergrounded.

The transmission line was constructed in 1969. While TXU has replaced deteriorated poles from time to

time over the years, the poles, taken as a whole, are in poor condition today. Many are bowed and lean

precariously (Figure 3-1). The poles are frequently struck by passing vehicles, especially large trucks. In

fact, steel plates have been installed on many poles to protect them from vehicle strikes.


Figure 3-1 - Existing Transmission and Distribution Line

TXU originally proposed to upgrade the existing Greenville - Lomo Alto 138-kV transmission line by

replacing every other pole with a new steel transmission pole. The intermediate poles would be cut off

above the distribution circuit. (Presumably, any defective intermediate poles would also be replaced.)

Because of public objection to the proposed heights of the poles, TXU then proposed to replace every pole

with a transmission pole, thereby reducing the pole heights by about 5 feet. Figure 3-2, prepared by TXU, is

a visual comparison of the existing line with a simulation of the line with all poles replaced.

Figure 3-2 - TXU Comparison of Existing and Proposed Transmission and Distribution Lines


With TXU’s proposed construction, there are two reasons why the replacement poles must be taller than the

existing structures:

1. The existing line was constructed with no overhead ground wire (OHGW) to protect (shield) it from lightning strikes. We are not sure why the line was not shielded, as virtually all transmission lines built in 1969 and since are shielded. In any case, the line is susceptible to lightning outages. TXU has added lightning arresters at several locations to the line. Even with the arresters, TXU reports that the line experienced three lightning outages during 2005. (A common design criteria for transmission lines is that a line should not experience more than one outage per year per 100 miles of line. For the Greenville - Lomo Alto line, which is about 3.5 miles in length, under this criteria, the line would not be expected to experience a lightning-caused outage more than once every 28 years on average.)

To add an OHGW to a transmission line, additional pole top is needed above the

conductors. In this case, 12-1/2 feet of additional pole is needed if the OHGW were attached to the pole. As an alternative, the additional pole top can be reduced if the OHGW is supported by a steel arm mounted at the top of the pole. With the steel arm, the additional pole needed above the conductors is reduced to 6 feet.

2. The existing line was configured with the three transmission wires in a “starburst”

configuration. Two wires are supported by post insulators mounted to the top of the pole in a horizontal orientation both left and right of the pole. The third wire is supported by a post insulator mounted to the top of the pole in a vertical orientation. There is no way to accommodate the vertical post when upgrading with an OHGW. Whereas the vertical spacing between the top and bottom transmission wires was about 6 feet with the original design, the spacing between the top and bottom wires must increase to 14 feet with the new design.

ALTERNATIVE OVERHEAD ROUTES

Sega investigated alternate routes to the existing Greenville - Lomo Alto transmission line.

Any alternate route in University Park would have to go down east-to-west city streets or alleys.

We see no advantage to placing the line on an alternate University Park street or alley.

The purpose of the Greenville - Lomo Alto transmission line is to provide a second feed to the

Lomo Alto substation. If a second feed could be provided to Lomo Alto from another source,

the Greenville - Lomo Alto line could possibly be eliminated. Such a source was identified as

the North Haven Substation, located approximately three miles north of Lomo Alto near the

Dallas Tollway. Sega investigated the possibility of the Lomo Alto - North Haven transmission


line. While it appears that the line could be placed on public (tollway) right-of-way part of the

way, it is evident that a significant part of the line would require easements along private

residential properties. It is believed to place a transmission line on one set of residences, so as to

eliminate an existing transmission line from a second set of residences, would not be politically

possible.

ALTERNATIVE OVERHEAD OPTIONS

Sega investigated various alternatives for the overhead transmission line. The first alternative is a

reconstruction of the line using the same configuration as now exists. (In order to improve lighting

performance, all insulators will be equipped with lightning arresters. The existing line has had arresters

added only at selected locations.) The remaining transmission alternatives add one or two overhead ground

wires for lightning protection. As a basis of comparison, the two TXU proposed configurations are being

evaluated (even though the public has expressed disapproval).

Selection of Pole Type

The line can be constructed with either steel or wood poles. From an engineering standpoint, either is

acceptable. The diameters of wood and steel poles are nearly the same for poles of equivalent size and

strength.

Wood poles come in various shades of brown, depending on the type of preservative treatment specified.

Steel poles are usually furnished with either galvanized coating (light gray) or weathering steel (dark

brown). Selection of the color or "look" of the pole is one of personal preference. Some prefer the brown

look, perhaps because they more resemble trees. Others prefer the look of galvanized poles because they

tend to blend into the sky. We make no recommendation as to type or color of the poles as this value

judgment is to be made by TXU and the City.

Wood poles have two disadvantages as compared to steel poles:

1. Wood poles deteriorate over time due to fungal and insect activity. 2. Wood poles can warp or decay over time, as has been the case with the existing line.


The wood poles are pressure treated when new to protect against fungal and insect decay, but that treatment

dissipates over time. Wood poles are, typically, inspected and given ground-line treatment on a regular

cycle (typically every 10 years) to extend the longevity of the pole, but interim replacements due to decay

are typical after several years.

Similarly, direct-embedded steel poles are given protection against ground-line corrosion by application of

corrosion sleeves and a polymeric coating (similar to that used for pipelines) at and below the ground line.

Steel poles are periodically inspected to assure that galvanic corrosion is not a problem, but, if so, sacrificial

anodes are installed to arrest the corrosion. Also, after many years, the zinc coating on galvanized poles can

become depleted, requiring painting of the poles. Properly maintained steel poles should not need interim

replacements.

The relative pricing between wood, galvanized, and weathering steel poles varies with the market. Right

now, the purchase cost of wood holds an advantage over equivalent steel poles. However, the installation

costs of wood poles are much heavier to handle than steel poles. Steel poles of the sizes used here are

furnished in two pieces, facilitating improved maneuverability in the narrow alleys. Also, right now,

weathering steel poles are less expensive than galvanized poles, as the price of zinc has skyrocketed in

recent months. The opinions of probable costs contained herein are based on galvanized steel poles, but our

opinion is that the selection of wood or weathering steel poles would not significantly alter the probable

costs, especially since market conditions are less likely to change between now and the time of construction.

Lightning Protection

A transmission line cannot be protected against lightning strikes. However, there are two methods used to

deal with the strikes that hit the line.

The most common method is to install one or more overhead ground wires (shield wires) at the top of the

structure to intercept the lightning stroke and carry the energy to the ground where it is dissipated. In this

way, the flow of current in the current-carrying conductors is not interrupted and dangerous electrical surges

do not stress electrical equipment at the substations.

Another way to deal with lightning is to install lightning arresters. This is most often done as a remedy to

existing lines that have experienced excessive lightning outages due to nonexistent or ineffective shielding.

The arrester does not prevent the lightning stroke from hitting the current-carrying conductors, but is


designed to absorb the bulk of the stroke energy and carry it to the ground for dissipation. This reduces the

surge voltage at the electrical equipment. There is one manufacturer of transmission line arresters.

According to the manufacturer's information, effective lightning protection is accomplished when arresters

are applied to all current-carrying conductors at every structure. The usual application is to install the

arresters in parallel with the insulators.

TXU has installed arresters to some, but not all, of the existing structures. As mentioned earlier, TXU has

experienced lightning-caused outages even after application of the arresters. The one alternative discussed

here, where an overhead ground wire is not used, is based on installing arresters at all insulators.

The Alternative Options

Alternative 1 is the existing configuration, but with the pole structures replaced with new materials. In

addition, lightning arrestors would be added to all insulators. With this alternative, most poles would

remain the same height as now exist. Figure 3-3 shows the current configuration. The pole is shown as 57

feet above ground. Most of the existing poles are 57 or 52-1/2 feet above ground with a few as short as 48

feet and a few as tall as 70 feet above ground.

Alternative 2 is the original TXU proposal where every other pole would be replaced with a new

transmission pole. The intermediate poles would be cut off above the distribution primary and the

transmission conductors would span over them. The advantage of this “skip span” construction is that fewer

poles would have to be replaced and longer spans are more economical for transmission line construction.

Figure 3-4 illustrates the pole configuration of Alternative 2. Figure 3-5 shows the configuration of the

intermediate distribution poles based on current TXU standards.

Alternative 3 is the same as Alternative 2, except every pole would be replaced with a new transmission

pole. The advantage of this alternative is that the poles would be about 5 feet shorter. The disadvantage is

increased cost. Also, some would consider the “picket fence” effect to be less attractive.

Alternative 4 is similar to Alternative 2, except the middle transmission insulator and conductor are

mounted on the opposite side of the pole from the top and bottom insulators. This is shown by Figure 3-6.

The advantage of this “delta” configuration is that the pole height is reduced by 7 feet. Disadvantages are

that the middle insulator and conductor overhang yards and would be more troublesome to maintain. Also,

a second OHGW and support arm must be added, increasing the cost.


Alternative 5 is to remove all under-build circuits and place them underground as promulgated by the 1989

master plan. This would leave only the transmission circuit. Without the undercircuits, the poles can be

shorter. Figure 3-7 illustrates the pole configuration for Alternative 5.

Alternative 6 is to remove the transmission line, but leave the undercircuits. The transmission line would

be built underground as explained elsewhere. The poles would be cut off above the distribution primary

and the undercircuits would be left as is. Figure 3-5 illustrates the typical distribution pole without the

transmission circuit.

Alternative 7 is to remove all overhead circuits and the supporting structures. Those circuits will be

placed underground as explained elsewhere.

Figure 3-8 shows the various overhead options side-by-side. Table 3-1 is a summary of the alternative

overhead options. Tables 3-2 through 3-7 are estimates of probable costs of the various overhead

alternatives.

Table 3-1Summary of Alternative Overhead Transmission Options

Typical TypicalTransmission Height Groundline Transmission Transmission Distribution Height Groundline Distribution

Span Height-Class Above Ground Diameter Conductor OHGW Span Height-Class Above Ground Diameter Conductor(ft) (ft-class) (ft) (in) (ft) (ft-class) (ft) (in)

Existing Line 13455-260-2

5257 13

636 kcmilACSR Rook None 134 n.a. n.a. n.a.

Existing636 kcmil

Alternative 1Replace Existing Line withCurrent Configuration;Install 100% Arresters 134

55-160-1

5257 14

Transfer Existing;

Design for 795 kcmil

ACSR Drake None 134 n.a. n.a. n.a.

Transfer Existing;


AAC Arbutus

Alternative 2 (TXU Proposal)New Transmission Poles With Intermediate Distribution Poles;Vertical Configuration 250 80-1 68 16

Transfer Existing;


ACSR Drake3/8-inch

Steel 125 40-2 34 12

Transfer Existing;


AAC Arbutus

Alternative 3 (TXU Proposal)New Transmission Poles With No Intermediate Distribution Poles;Vertical Configuration 125 75-1 64 16

Transfer Existing;


ACSR Drake3/8-inch

Steel 125 n.a. n.a. n.a.

Transfer Existing;


AAC Arbutus

Alternative 4New Transmission Poles With Intermediate Distribution Poles;Delta Configuration 250 75-1 61 16

Transfer Existing;


ACSR Drake3/8-inch

Steel 125 40-2 34 12

Transfer Existing;


AAC Arbutus

Alternative 5New Transmission Poles With No Underbuilds; Vertical Configuration; Bury Underebuilds 250 60-2 50 13

Transfer Existing;


ACSR Drake3/8-inch

Steel n.a. n.a. n.a. n.a. n.a.

Alternative 6Remove Transmission; Leave Underbuilds; Cut Tops Off Poles n.a n.a. n.a. n.a. n.a n.a 134 Existing 34 13 Existing

Alternative 7Remove all Overhead Circuits n.a n.a. n.a. n.a. n.a n.a. n.a. n.a. n.a n.a. n.a

Typical Distribution PoleTypical Transmission Pole

Distribution DistributionNeutral Secondary

Existing636 kcmil

Existing636 kcmil

Transfer Existing;

Design for #2 AAC

Iris

Transfer Existing;

Design for 4/0 TriplexPortunus

Transfer Existing;

Design for #2 AAC

Iris

Transfer Existing;


Transfer Existing;

Design for #2 AAC

Iris

Transfer Existing;


Transfer Existing;

Design for #2 AAC

Iris

Transfer Existing;


n.a. n.a.

Existing Existing

n.a. n.a.

Table 3-2

University ParkOverhead Transmission Line Cost EstimateAlternative 1 - "Status Quo Configuration"

Upgrade 1-Circuit 138-kV Transmission CircuitInstall Arrestors at all InsulatorsTransfer 3-Phase Distribution Primary UnderbuildTransfer 1-Phase Distribution SecondaryTransfer Telephone and CATV UnderbuildsTubular Steel Transmission Poles125-foot Transmission Spans2.72 Mile Length

5/19/2006 0:00

MaterialMaterial Labor + Labor Extended

Unit Unit Quantity Unit Price Unit Price Unit Price Price

Transmission CircuitRemove Existing Transmission Pole ea 111 $0 $3,000 $3,000 $333,000Tangent Steel Pole (65'-1) ea 111 $3,254 $6,508 $9,762 $1,083,582Deadend Steel Pole ea 4 $26,278 $26,278 $52,556 $210,224Deadend Foundations ea 4 $50,000 $50,000 $200,000Transfer 636 kcmil ACSR Rook ft 43110 $0 $5 $5 $215,550138-kV Post Insulator Assembly ea 445 $700 $535 $1,235 $549,575138-kV Strain Insulator Assembly ea 24 $643 $715 $1,358 $32,592138-kV Arrestors ea 469 $600 $200 $800 $375,200138-kV Jumper Posts ea 12 $462 $535 $997 $11,964Mounting Bolts and Nuts,1 Lot ea 1 $5,500 $0 $5,500 $5,500Pole Grounding ea 55 $50 $350 $400 $22,000

$3,039,187

Distribution and Communication CircuitsCut Tops for Intermediate Distribution Poles ea 0 $0 $0 $0 $0Primary Crossarms for New Poles ea 111 $150 $90 $240 $26,640Neutral Attachments for New Poles ea 111 $40 $30 $70 $7,770Secondary Attachments for New Poles ea 111 $40 $30 $70 $7,770Telcommunication Attachments for New Poles ea 222 $40 $30 $70 $15,540Transfer 3-Phase Primary ft 43110 $0 $5 $5 $215,550Transfer Neutral ft 14370 $0 $5 $5 $71,850Transfer Secondary ft 14370 $0 $5 $5 $71,850Transfer Telephone ft 14370 $0 $5 $5 $71,850Transfer CATV ft 14370 $0 $5 $5 $71,850

$560,670

Total Transmission + Distribution $3,599,857

Contingency 25% $899,964

Total $4,499,821

Table 3-3

University ParkOverhead Transmission Line Cost EstimateAlternative 2 - Vertical Configuration, Skip Span

Upgrade 1-Circuit 138-kV Transmission CircuitTransfer 3-Phase Distribution Primary UnderbuildTransfer 1-Phase Distribution SecondaryTransfer Telephone and CATV UnderbuildsTubular Steel Transmission Poles250-foot Transmission SpansIntermediate Wood Distribution Poles (Existing)2.72 Mile Length

5/19/2006 0:00



Transmission CircuitRemove Existing Transmission Pole ea 55 $0 $3,000 $3,000 $165,000Tangent Steel Pole (80'-1) ea 55 $4,782 $9,564 $14,346 $789,030OHGW Davit Arm ea 55 $100 $50 $150 $8,250Deadend Steel Pole ea 4 $26,278 $26,278 $52,556 $210,224Deadend Foundations ea 4 $50,000 $50,000 $200,000Install 3/8-inch OHGW ft 14370 $0.5 $3.0 $3.5 $50,295Transfer 636 kcmil ACSR Rook ft 43110 $0 $5 $5 $215,550OHGW Suspension Assy ea 55 $75 $180 $255 $14,025OHGW Deadend Assy ea 8 $204 $830 $1,034 $8,272138-kV Post Insulator Assembly ea 445 $700 $535 $1,235 $549,575138-kV Strain Insulator Assembly ea 24 $643 $715 $1,358 $32,592138-kV Jumper Posts ea 12 $462 $535 $997 $11,964Mounting Bolts and Nuts,1 Lot ea 1 $5,500 $0 $5,500 $5,500Pole Grounding ea 55 $50 $350 $400 $22,000

$2,282,277

Distribution and Communication CircuitsCut Tops for Intermediate Distribution Poles ea 56 $0 $500 $500 $28,000Primary Crossarms for New Poles ea 55 $150 $90 $240 $13,200Neutral Attachments for New Poles ea 55 $40 $30 $70 $3,850Secondary Attachments for New Poles ea 55 $40 $30 $70 $3,850Telcommunication Attachments for New Poles ea 110 $40 $30 $70 $7,700Transfer 3-Phase Primary ft 43110 $0 $5 $5 $215,550Transfer Neutral ft 14370 $0 $5 $5 $71,850Transfer Secondary ft 14370 $0 $5 $5 $71,850Transfer Telephone ft 14370 $0 $5 $5 $71,850Transfer CATV ft 14370 $0 $5 $5 $71,850

$559,550



Total $3,552,284

Table 3-4

University ParkOverhead Transmission Line Cost EstimateAlternative 3 - Vertical Configuration, Span-for-Span

Upgrade 1-Circuit 138-kV Transmission CircuitTransfer 3-Phase Distribution Primary UnderbuildTransfer 1-Phase Distribution SecondaryTransfer Telephone and CATV UnderbuildsTubular Steel Transmission Poles125-foot Transmission Spans2.72 Mile Length

5/19/2006 0:00



Transmission CircuitRemove Existing Transmission Pole ea 111 $0 $3,000 $3,000 $333,000Tangent Steel Pole (75'-1) ea 111 $4,400 $8,800 $13,200 $1,465,200OHGW Davit Arm ea 111 $100 $50 $150 $16,650Deadend Steel Pole ea 4 $26,278 $26,278 $52,556 $210,224Deadend Foundations ea 4 $50,000 $50,000 $200,000Install 3/8-inch OHGW ft 14370 $0.5 $3.0 $3.5 $50,295Transfer 636 kcmil ACSR Rook ft 43110 $0 $5 $5 $215,550OHGW Suspension Assy ea 55 $75 $180 $255 $14,025OHGW Deadend Assy ea 8 $204 $830 $1,034 $8,272138-kV Post Insulator Assembly ea 445 $700 $535 $1,235 $549,575138-kV Strain Insulator Assembly ea 24 $643 $715 $1,358 $32,592138-kV Jumper Posts ea 12 $462 $535 $997 $11,964Mounting Bolts and Nuts,1 Lot ea 1 $5,500 $0 $5,500 $5,500Pole Grounding ea 55 $50 $350 $400 $22,000

$3,134,847

Distribution and Communication CircuitsCut Tops for Intermediate Distribution Poles ea 0 $0 $0 $0 $0Primary Crossarms for New Poles ea 111 $150 $90 $240 $26,640Neutral Attachments for New Poles ea 111 $40 $30 $70 $7,770Secondary Attachments for New Poles ea 111 $40 $30 $70 $7,770Telcommunication Attachments for New Poles ea 222 $40 $30 $70 $15,540Transfer 3-Phase Primary ft 43110 $0 $5 $5 $215,550Transfer Neutral ft 14370 $0 $5 $5 $71,850Transfer Secondary ft 14370 $0 $5 $5 $71,850Transfer Telephone ft 14370 $0 $5 $5 $71,850Transfer CATV ft 14370 $0 $5 $5 $71,850

$560,670



Total $4,619,396

Table 3-5

University ParkOverhead Transmission Line Cost EstimateAlternative 4 - Delta Configuration, Skip Span

Upgrade 1-Circuit 138-kV Transmission CircuitTransfer 3-Phase Distribution Primary UnderbuildTransfer 1-Phase Distribution SecondaryTransfer Telephone and CATV UnderbuildsTubular Steel Transmission Poles250-foot Transmission SpansIntermediate Wood Distribution Poles (Existing)2.72 Mile Length

5/19/2006 0:00



Transmission CircuitRemove Existing Transmission Pole ea 55 $0 $3,000 $3,000 $165,000Tangent Steel Pole (75'-1) ea 55 $4,400 $8,800 $13,200 $726,000OHGW Davit Arm ea 110 $100 $50 $150 $16,500Deadend Steel Pole ea 4 $26,278 $26,278 $52,556 $210,224Deadend Foundations ea 4 $50,000 $50,000 $200,000Install 3/8-inch OHGW ft 28740 $0.5 $3.0 $3.5 $100,590Transfer 636 kcmil ACSR Rook ft 43110 $0 $5 $5 $215,550OHGW Suspension Assy ea 110 $75 $180 $255 $28,050OHGW Deadend Assy ea 16 $204 $830 $1,034 $16,544138-kV Post Insulator Assembly ea 445 $700 $535 $1,235 $549,575138-kV Strain Insulator Assembly ea 24 $643 $715 $1,358 $32,592138-kV Jumper Posts ea 12 $462 $535 $997 $11,964Mounting Bolts and Nuts,1 Lot ea 1 $5,500 $0 $5,500 $5,500Pole Grounding ea 55 $50 $350 $400 $22,000

$2,300,089

Distribution and Communication CircuitsCut Tops for Intermediate Distribution Poles ea 56 $0 $500 $500 $28,000Primary Crossarms for New Poles ea 55 $150 $90 $240 $13,200Neutral Attachments for New Poles ea 55 $40 $30 $70 $3,850Secondary Attachments for New Poles ea 55 $40 $30 $70 $3,850Telcommunication Attachments for New Poles ea 110 $40 $30 $70 $7,700Transfer 3-Phase Primary ft 43110 $0 $5 $5 $215,550Transfer Neutral ft 14370 $0 $5 $5 $71,850Transfer Secondary ft 14370 $0 $5 $5 $71,850Transfer Telephone ft 14370 $0 $5 $5 $71,850Transfer CATV ft 14370 $0 $5 $5 $71,850

$559,550



Total $3,574,549

Table 3-6

University ParkOverhead Transmission Line Cost EstimateAlternative 5 - Vertical Configuration, Under Circuits Removed

Upgrade 1-Circuit 138-kV Transmission CircuitDistribution and Communication Circuits Removed250-foot Transmission Spans2.72 Mile Length

5/19/2006 0:00



Transmission CircuitRemove Existing Transmission Pole ea 111 $0 $3,000 $3,000 $333,000Tangent Steel Pole (60-2) ea 55 $2,608 $2,608 $5,216 $286,880OHGW Davit Arm ea 55 $100 $50 $150 $8,250Deadend Steel Pole ea 4 $26,278 $26,278 $52,556 $210,224Deadend Foundations ea 4 $50,000 $50,000 $200,000Install 3/8-inch OHGW ft 14370 $0.5 $3.0 $3.5 $50,295Transfer 636 kcmil ACSR Rook ft 43110 $0 $5 $5 $215,550OHGW Suspension Assy ea 55 $75 $180 $255 $14,025OHGW Deadend Assy ea 8 $204 $830 $1,034 $8,272138-kV Post Insulator Assembly ea 445 $700 $535 $1,235 $549,575138-kV Strain Insulator Assembly ea 24 $643 $715 $1,358 $32,592138-kV Jumper Posts ea 12 $462 $535 $997 $11,964Mounting Bolts and Nuts,1 Lot ea 1 $5,500 $0 $5,500 $5,500Pole Grounding ea 55 $50 $350 $400 $22,000

$1,948,127

Distribution and Communication CircuitsRemove 3-Phase Primary ft 43110 $0 $5 $5 $215,550Remove Neutral ft 14370 $0 $5 $5 $71,850Remove Secondary ft 14370 $0 $5 $5 $71,850Remove Telephone ft 14370 $0 $5 $5 $71,850Remove CATV ft 14370 $0 $5 $5 $71,850

$502,950



Total $3,063,846

Table 3-7

University ParkOverhead Transmission Line Cost EstimateAlternative 6 - Remove Transmission, Leave Under Circuits

Remove 1-Circuit 138-kV Transmission CircuitDistribution and Communication Circuits Untouched125-foot Spans2.72 Mile Length

5/19/2006 0:00



Transmission CircuitCut Top off Existing Transmission Pole ea 111 $0 $500 $500 $55,500Remove 636 kcmil ACSR Rook ft 43110 $0 $5 $5 $215,550

$215,550


Total $269,438

Table 3-8

University ParkOverhead Transmission Line Cost EstimateAlternative 7 - Remove Overhead Lines in Entirety

Upgrade 1-Circuit 138-kV Transmission CircuitDistribution and Communication Circuits Removed250-foot Transmission Spans2.72 Mile Length

5/19/2006 0:00



Transmission CircuitRemove Existing Transmission Pole ea 111 $0 $1,000 $1,000 $111,000Remove 636 kcmil ACSR Rook ft 43110 $0 $5 $5 $215,550

$326,550

Distribution and Communication CircuitsRemove 3-Phase Primary ft 43110 $0 $5 $5 $215,550Remove Neutral ft 14370 $0 $5 $5 $71,850Remove Secondary ft 14370 $0 $5 $5 $71,850Remove Telephone ft 14370 $0 $5 $5 $71,850Remove CATV ft 14370 $0 $5 $5 $71,850

$502,950

Total Transmission + Distribution $829,500


Total $1,036,875

SECTION 4

UNDERGROUND TRANSMISSION ROUTES


UNDERGROUND TRANSMISSION ROUTES

INTRODUCTION

TXU Electric Delivery (TXU) is proposing to rebuild the 138-kV transmission line between its Greenville

and Lomo Alto Substations using steel pole structures. As a result of concerns of some of the citizens of

the City of University Park, Texas, Sega Inc. and its subcontractor, Power Delivery Consultants, Inc.

(PDC), were commissioned to prepare underground transmission alternatives to the TXU proposed

overhead line. This document describes preliminary designs and cost estimates for two underground

transmission alternatives.

PDC is an engineering services company that specializes in the design and specification of underground

transmission lines. PDC has prepared cost estimates, completed preliminary designs, and provided

specifications for six underground transmission lines in the State of Texas. These include the 8.5-mile,

138-kV XLPE underground transmission line between Port Isabel and South Padre Island and the

relocation of 6 miles of two, 138-kV overhead transmission lines for widening of the Katy Freeway in

Houston.

TRANSMISSION LINE ALIGNMENTS

The existing TXU Greenville - Lomo Alto 138-kV underground transmission line in the City of University

Park is constructed on wood poles that are primarily located in alleys between residential streets. The

existing wood poles support a 138-kV transmission line as well as a distribution line, pole-mounted

distribution transformers, and some residential service cables.

Early during the Study effort, Sega was informed that the City of Highland Park was considering

replacing an underground water line that resides beneath Mockingbird Lane. This would require major

excavation and disruption of traffic during construction. It was felt that, while such disruption was

underway, it might be an opportunity to install underground cables coincident with the water line project.

However, we understand that Highland Park has now decided not to excavate, but rather repair the water

line in situ. There would, therefore, be no advantage to locating the underground line along Mockingbird

as compared to any other east-to-west street in University Park.


PDC considered the following two alternatives for constructing an underground transmission line to replace

the existing 138-kV overhead transmission line. This document does not address the future disposition of

the distribution lines on the wood poles.

Existing Right-Of-Way

The first underground alternative (UG1) that was investigated was to construct a 138-kV underground

transmission line along the alignment for the existing 138-kV overhead transmission line. However, there

are numerous challenges to construct a conventional open-trench underground transmission line down the

narrow alley where the existing line is located. The following issues make this underground alternative

difficult and expensive to construct.

There are numerous underground utilities (i.e., sewer, gas, and water) in the alleys that would have to be

relocated to excavate the transmission cable trench or the widths of the alleys would have to be increased to

facilitate excavation of the cable trench.

The widths of the existing alleys are too narrow to accommodate a conventional, open-cut cable trench. This

being the case, the width of the alleys would have to be increased to the size of the existing utilities. More

specifically, the increased right-of-way width would have to be on the side of the alley that is opposite from

the existing wooden poles. Widening the alleys would require acquisition of property from local residents

and existing structures would have to be relocated or modified in some cases. The seven or eight splice

vaults for the underground transmission cables (typically 8-feet wide by 20-feet long by 7-feet high) would

have to be located in the side streets for the majority of the existing alignment.

Because of the above construction issues, the only technically feasible method of constructing the

underground transmission line along the existing alignment would be to use a trenchless construction

method called horizontal directional drilling (HDD). In this case, HDD rigs would bore beneath the existing

utilities (20 to 30 feet below the surface) with splice vaults installed on side streets. Additional details of the

HDD equipment and limitations are presented in a following section.

Closest City Streets

The second and preferred alternative (UG2) for constructing the underground transmission line is to

construct the line in the closest City streets to the existing overhead transmission line. In this case,

conventional open-cut excavation equipment (e.g., backhoes and/or trackhoes) would be used to excavate a


trench along one of the closest City streets to the existing alignment and a concrete-encased duct bank would

be installed to accommodate subsequent installation of the transmission cables. The seven or eight concrete

vaults would be installed in the City streets for splicing of the transmission cables.

UNDERGROUND TRANSMISSION TECHNOLOGIES

Several cable system types could be used for the 138-kV underground transmission line: High-pressure,

fluid-filled (HPFF); high-pressure, gas-filled (HPGF); extruded-dielectric (ED); and self-contained, fluid-

filled (SCFF). These systems are described in the following sections.

Extruded-Dielectric Cable, XLPE, and EPR

ED cables have an extruded insulation that requires no pressurization. They can, therefore, be installed

individually in plastic ducts, similar to distribution cables. ED cables with cross-linked polyethylene

(XLPE) insulation are subject to “water trees” just as distribution cables are; therefore, the transmission

cables always have a metallic moisture barrier. Lead is traditionally used and is considered the best

material, but aluminum and copper moisture barriers and laminates of these materials are becoming

common. Ethylene Propylene Rubber (EPR) insulation is installed without a moisture barrier because of its

better resistance to damage from moisture. Ducts are typically PVC provided in 10-foot or 20-foot lengths,

held in place with spacers and encased in concrete, but the duct size for a 138-kV cable is nominal 6 inches

(6.625-inches OD) versus the nominal 5-inch ducts used for distribution cables. Transmission cables

typically require thicker, Schedule 40 ducts. Figure 1 shows a 138-kV XLPE cable.

Figure 4-1 - ED (XLPE) Insulated Cable


High-Pressure, Fluid-Filled Cable

Each cable consists of a conductor, typically copper, and has approximately 0.44 inches of insulation

consisting of helically-applied paper tapes that are factory impregnated with a very high-viscosity, dielectric

liquid. The three cables for the three-phase system are approximately 3- to 3.5-inches in diameter and are

installed in a coated and cathodically protected 8-5/8-inch OD, 0.25-inch wall mild steel pipe. The pipe is

provided in double-random lengths 45- to 55-feet long. Pipe ends are flared at the coating facility and

backing rings are inserted to align the pipe ends in the field to provide a smooth inner profile and prevent

weld slag from entering the pipe during welding. The welds are x-rayed and tested with a holiday detector

after coating is applied in the weld area. After the three cables are pulled simultaneously into the pipe and

spliced and terminations are installed, the pipe is evacuated and pressurized with a dielectric fluid

(alkylbenzene or polybutene) to a nominal 200-psig pressure to maintain the electrical strength of the

insulation. Figure 4-2 shows a pipe-type cable.

Figure 4-2 - Typical Pipe-Type Cable

High-Pressure, Gas-Filled Cable

High-pressure, gas-filled (HPGF) cables have the same general construction as the HPFF pipe-type cable,

except that the pipe is filled with dry nitrogen gas pressurized at 200 psig. The insulation thickness is

slightly thicker (0.5 inch) for this type of cable system.

Self-Contained, Fluid-Filled (SCFF) Cable

The cables have copper conductors with hollow cores through which dielectric liquid is passed to pressurize

the wrapped paper insulation. The cables are installed individually in plastic ducts. This type is seldom

used on land cables (it is very common on submarine cables) and was not evaluated for this Study.


Figure 4-3 - Typical SCFF Cable

Advantages and Disadvantages of Each Cable Type

Advantages Disadvantages

HPFF • Proven, reliable system; in service at 138-kV • Insulation thickness slightly greater and

70 years ampacity slightly lower than SCFF system • Steel pipe provides good mechanical protection • Specialized equipment needed for installation • Lower magnetic fields than other cable types and repair • Can be installed somewhat more quickly • Electrical losses and charging currents higher than ED cables than for ED cables • Ratio of normal-to-emergency ampacity • Restoration time is longer than ED typically higher than for XLPE or EPR cables • U.S. supplier and several U.S. installers

ED • No dielectric fluid or fluid pressurizing • Splices and terminations have been a problem equipment is required in some cases • Less complex cable system • Less forgiving of defects in manufacturing/ • Lower dielectric losses and VARS than installation HPFF cable • Necessary to have splices and terminations • No special precautions for circuit restoration supplied by the cable supplier and preferably • Installation can use same equipment as installed by cable factory technicians. distribution cables • Complex sheath bonding methods; sheath • More than a dozen suppliers world-wide

(and a U.S. supplier) voltages can be a problem

SCFF • Proven, reliable system, in service at 138-kV • Most complex of the cable systems for 70 years • Highest maintenance • No domestic suppliers


University Park Application

The project team selected the ED cable (XLPE insulation) system to be the best transmission cable

technology for the City of University Park underground transmission line alternative. We believe that an

XLPE transmission cable system is best suited for this application for the following reasons:

1. It currently is the most common type of 138-kV transmission cable system being installed in the U.S. and most other places in the world.

2. Minimal space is required for overhead-to-underground transitions. One of the most

common ways of making overhead to underground transitions for XLPE cable systems are pole-mounted terminations as shown in Figure 4-4. Overhead-to-underground transitions for HPFF cable installations are generally constructed by ground-level, fenced-in areas similar to a small substation. Usually, at least one of the two ends is terminated in a substation because a fluid pressurization unit is required.

3. Minimal maintenance is required for this type of cable system.

Figure 4-4 - Typical Overhead-to-Underground Transition for 138-kV XLPE Cable System TXU has both HPFF and XLPE transmission cables at different locations on its transmission system and

indicated that it would consider either type (HPFF or XLPE) of transmission cable as underground

alternatives for the Greenville - Lomo Alto line.


DESIGN REQUIREMENTS

A preliminary underground transmission cable system design was completed prior to preparing cost

estimates for the two underground system alternatives. The technical design requirements that were

assumed for the underground transmission alternatives were:

1. Transmission Capacity: The electric-power transmission capacity of the underground transmission line must be equal to the power transmission capacity of the overhead transmission line alternatives. The largest conductor size that can be supported by steel pole replacements for the wood poles would be 795 kcmil ACSR. The current-carrying rating of this type of conductor and typical span lengths would be approximately 1,000 amperes. For underground transmission systems, the 24-hour load factor (a measure of daily load variability) is an important design parameter. PDC assumed a 24-hour load factor of 75 percent based on typical underground transmission line design criteria provided by TXU (Lemmon Avenue Substation Underground Transmission Project).

2. 138-kV XLPE Transmission Cables: The XLPE transmission cable technical

specifications provided by TXU were used for the preliminary design. TXU’s specifications for 138-kV transmission cables is a lead-sheath cable with 0.850-inch thick XLPE insulation that comply with U.S. industry specifications for this type of cable (AEIC CS7-93 - Specifications for Cross-Linked, Polyethylene, Insulated, Shielded Power Cables Rated 69 through 138 kV). AEIC CS7-93 specifies a maximum conductor temperature of 90 degrees C for normal operating conditions.

3. Cable System Grounding: XLPE transmission cable system sheaths are typically

grounded using special methods to minimize induced sheath currents. These special bonding methods to reduce induced sheath currents result in induced sheath voltages. TXU’s specifications require that the induced sheath voltages do not exceed 150 volts during normal operating conditions. This requirement is one constraint that determines the maximum distance between cable manholes (splice vaults).

4. Cable Pulling Tensions and Sidewall Bearing Pressure: Other design constraints are the

maximum pulling tension that can be applied to the cables during installation and the maximum pressure applied to the cable as it is pulled around bends in the duct bank. These constraints also limit the maximum distance between splice vaults. AEIC G1 recommendations for maximum pulling tension and sidewall bearing pressure were taken into account when performing preliminary design calculations for the underground transmission alternatives.

CONSTRUCTION METHODS

Construction methods assumed for the two underground alternatives are described in the following sections.


Horizontal Directional Drilling (UG1)

As discussed in Section 2, HDD is the only feasible method for installing underground transmission cables

along the alignment for the existing 138-kV transmission line. This is due to the narrow alleys and existing

underground utilities. Figure 4-5 shows a typical cross section of a 138-kV XLPE transmission line using

HDD boring. The 28-inch diameter bore would be constructed at a depth of 25 to 35 feet below the surface

of the ground, depending on the mechanical properties of the soil along the transmission line alignment.

The next step in the HDD process is to drill a pilot hole and then back-ream the pilot bore to expand the

bore diameter to 28 inches (Figure 4-5). Set-up areas for the drilling rigs must be large enough to

accommodate the equipment for containing and processing the drilling mud (water/bentonite slurry).

The next step in the construction process (Figure 4-6) is to assemble strings of the HDPE pipes that are long

enough to be pulled into the entire length of the bore and pull them into the bore.


Transmission Cable

28-inch ö HDD Bore

Drilling Mud and Soil

6-inch SDR 11 HDPE Pipe

Figure 4-5 - HDD Bore Cross Section

Figure 4-6 - HDPE Pipe Strings

HDD rigs (Figure 4-7) are available that can be used to construct bores several feet in diameter for bore

lengths over one mile; however, they require a large amount of area (i.e., 100 by 150 feet) to accommodate

auxiliary equipment, such as drilling mud processing and storage equipment, cranes, and stockpiles of drill

pipe. Another limitation for XLPE underground transmission cables is the maximum cable pulling length of

approximately 3,000 feet.


Figure 4-7 - Large HDD Boring Rig Used for 3,500-Foot Bore

The set-up area for midi-size HDD rigs (Figure 4-8) and auxiliary equipment could be accommodated on

side streets for the City of University Park underground Alternative 1, but the maximum bore length for a

28-inch diameter bore is approximately 1,200 to 1,300 feet, depending on soil conditions.

Figure 4-8 - Midi-Size HDD Boring Rig Used for 1,200-Foot Bore


Concrete-Encased Duct Bank Construction (UG2)

XLPE transmission cable underground transmission lines are typically constructed in urban and suburban

environments using concrete-encased duct banks (see Figure 4-9).

Figure 4-9 - Typical XLPE Transmission Cable Duct Bank Installation

Concrete-encased duct banks are typically used in City streets because the length of open trench at any

one time during construction can be limited to 300 or 400 feet. The transmission cables are then installed

after the duct bank construction and splice vault installation have been completed. Concrete-encased

duct banks also provide good mechanical protection against dig-ins after they have been placed in

service.

Figure 4-10 shows a trench cross section for the street construction alternative (UG2).


Figure 4-10 - Trench Cross Section for Street Construction (UG2)


Figure 5-5. Trench cross section for street construction (UG2)

City of University Park Power Delivery Consultants, Inc. Transmission Cable Splice Vaults

The transmission cable splices for both alternatives would be installed in pre-fabricated concrete vaults

approximately 20-feet long, 7-feet wide, and 7-feet high (see Figures 4-11 and 4-12).

Figure 4-11 - Concrete Splice Vault

7'

Figure 4-12 - Pre-fabricated Concrete Splice vaults

7'


CABLE INSTALLATION

The cables are shipped to the construction site on large reels that are approximately 12-feet high by 8-feet

wide and pulled into the cable ducts or HDPE pipes one at a time (Figure 4-13) with a cable winch (Figure

4-14) at the opposite end of the cable duct.

Figure 4-13 - Cable Pulling Into Concrete-Encased Duct Bank

Figure 4-14 - Cable Pulling Wench


The cable splicing activities (Figure 4-15) at each of the manholes takes approximately one week.

Figure 4-15 - Cable Splicing in Concrete Vault

UNDERGROUND ALIGNMENTS

The alignments for the two underground transmission alternatives roughly follow the path of the existing

overhead transmission line from the eastern City limit at the North Central Expressway to the western City

limit at the North Tollway where the existing line turns south to the Lomo Alto substation. It was assumed

that overhead-to-underground transitions (riser poles) would be installed at both of these locations.

Additional details of the two underground alternatives that were selected by the Sega/PDC team are given in

the following sections.

Existing Right-of-Way

The eastern overhead-to-underground transitions would occur at a small park located at the intersection of

Willard and Daniel (Figure 4-16).


Figure 4-16 - Proposed Location for Eastern Overhead-to-Underground Transition


Figure 4-17 - Alignment for Underground Alternative 1 (UG1)

The alignment for this option would proceed from east to west as follows: 1. The first section of the alignment would be concrete-encased duct bank from the riser pole to the

eastern end of the alley between Daniel and Rosedale (approximately 200 feet). 2. The transmission cables would then be installed beneath the alley (between Daniel and Rosedale)

using HDD with the bore machine set up in the small park shown in Figure 4-17. The opposite end of the HDD bore and first manhole would be located in the street at Boedeker. This is a distance of approximately 1,100 feet.

3. The underground transmission line would then turn 90 degrees to the north and proceed to the

alley between Amherst and Stanford. It would be installed beneath the surface of Boedeker Street in a concrete-encased duct bank using conventional open-cut excavation, except where it crosses Lovers Lane. A construction method called pipe jacking and boring would be used to install a steel casing or reinforced concrete pipe (RCP) beneath Lovers Lane to avoid disruption of the traffic of this relatively busy street.

4. The alignment would turn 90 degrees to the west at the alley between Amherst and Stanford. The

underground transmission line would then follow the existing transmission line route from Boedeker to Lomo Alto where it would return to overhead construction via a second riser pole. The underground transmission cables would be installed beneath the alley located between Amherst and Stanford using HDD. This distance of approximately 2.1 miles would be traversed by means of 10 bores shown in Table 3-1 with six manholes located on the side streets.

Stanford Splice Vault

Amherst


Number End 1 End 2 Distance (ft)

1 Boedeker Durham 945 2 Durham Airline 775 3 Airline Hillcrest 1,185 4 Hillcrest Dickens 915 5 Dickens Thackery 730 6 Thackery Baltimore 1,130 7 Baltimore Tulane 1,130 8 Tulane Preston 1,130 9 Preston Douglas 1,290

10 Douglas Lomo Alto 1,230

Table 4-1 - HDD Bores between Boedeker and Lomo Alto


The number of HDD bores could be significantly reduced if there were space to set up the full-size HDD

boring machines. However, the side streets along the alignment are only wide enough to accommodate the

midi-size HDD rigs shown in Figure 4-7 and the maximum distance for this type of rig is approximately

1,200 to 1,300 feet.

There would be a total of seven splice vaults for the above underground alignment. Several of the shorter

bores would be connected without splice vaults.

Closest City Streets

The second underground alternative (UG2) would start at the same overhead-to-underground transition

location as the first underground alternative (see Figure 4-17 and Figure 4-18).

Stanford

Rosedale

Daniel

Figure 4-18 - Alignment for Underground Alternative 1 (UG2)

Splice Vault

Amherst

Lovers Lane


The underground transmission line would then be constructed in City streets as follows:

1. The cables would be installed in concrete-encased duct bank from the riser pole in the small park to Rosedale where it would turn west.

2. The concrete-encased duct bank would then proceed west along Rosedale to

Boedeker where it would turn north on Boedeker. 3. The cable duct bank would then follow Boedeker to Stanford where it would

turn 90 degrees to the west. As in the previous underground alternative, pipe jacking and boring would be used to install the cables in a steel casing beneath Lovers Lane.

4. The cable duct bank would then follow Stanford to Lomo Alto where a

transition would be made from underground construction to overhead construction at a second riser pole.

The cable duct bank would be installed with a minimum cover of 36 inches for the majority of the

alignment. There are six locations where the duct bank will have to dip beneath existing storm and

sanitary sewers. The deepest of these is between Tulane and Baltimore where a 15-inch sanitary

sewer is installed below a large box culvert storm sewer. The cable duct bank would have to dip

below both of these facilities with a depth to the top of the duct bank of 14 feet.

The underground alignment for this alternative between Boedeker and Lomo Alto could be

constructed along Amherst rather than Stanford. There would be eight manholes for the above

underground transmission alignment.

The second UG (i.e., closest City streets) is the favored alternative because: 1. There are very few underground utilities located in Stanford and Amherst. 2. It is less expensive to construct concrete-encased duct bank compared to the

HDD. 3. There are fewer construction uncertainties with conventional open-cut

construction compared to HDD construction.


CABLE SIZING

Ampacity calculations were performed to determine the cable conductor sizes that will be

necessary to achieve an ampacity rating of 1,000 amperes for the two underground transmission

alternatives. The design parameters shown in Table 4-2 were used to perform the ampacity

calculations.

Parameter Value Units 24-Hour Load Factor 75 Percent Native Soil Thermal Resistivity 70 °C - cm/W Maximum Soil Ambient Temperature at 6-Foot Depth 25 °C Maximum Soil Ambient Temperature at 30-Foot Depth 22 °C Concrete-Encasement Thermal Resistivity 60 °C - cm/W HDD Grout Thermal Resistivity 80 °C - cm/W Maximum Conductor Temperature, Normal Operation 90 °C Maximum Conductor Temperature, Emergency Operation 105 °C Burial Depth (Top of Duct Bank) 3 to 9 ft Burial Depth (Top of HDD Bore) 25 to 35 ft

Cable Sheath Bonding Cross-Bonding and Single-Point --

Table 4-2 - Ampacity Calculation Parameters

Results of the ampacity calculations are shown in Table 4-3.

Construction Depth (ft)

Copper Conductor Size

(kcmil) Conductor Stranding

Ampacity (A)

2x2 Duct Bank 4 1,750 Compressed Concentric 1,118


2x2 Duct Bank 9 1,750 Compact Segmental 1,133


2x2 Duct Bank 14 1,750 Compact Segmental 1,104

HDD HDPE Pipe 30 1,750 Compressed Concentric 987

HDD HDPE Pipe 30 1,750 Compact Segmental 1,054

Table 4-3 - Results of Ampacity Calculations


In summary, the ampacity calculations indicate that a 1,750 kcmil compressed round copper

conductor will meet the 1,000-ampere ampacity target at all locations for the concrete-encased

duct bank UG2 alternative.

A 1,750-kcmil compact segmental copper conductor will be required to meet the ampacity

requirement for the HDD (UG1) installation alternative. The segmental conductor increases the

cable rating by reducing skin effect losses.

OPINION OF PROBABLE COSTS

Probable costs were prepared for both underground cable system alternatives based on PDC’s

observations from several recent XLPE transmission cable projects. Details of the probable costs

are shown at the end of this Section.

The following assumptions were made in preparing probable costs for the 2.7-mile long

underground transmission line:

1. A single contract would be issued to engineer, procure, and construct (EPC) the

underground transmission line. It is common for utilities to award a single EPC or turn-key contract to a transmission cable construction company or cable company to take full responsibility for the design, supply of material, and construction of the underground transmission line.

2 No right-of-way or easement costs are included. It is assumed that the

underground transmission line will be constructed on the existing right-of-way for the overhead line or that the City of University Park will issue easements where the underground lines are constructed in City streets. Any fees that are required to extend the existing right-of-way agreements for underground constructions should be added to the probable costs in this document.

3. Cable and accessory costs are based on current typical costs for this equipment

and PDC’s estimate of the costs during the next 12-month period. It should be noted that the cost of transmission cable and, to a lesser extent, transmission cable accessories fluctuate significantly, depending on the cost of metals, other market conditions, and foreign currency exchange rates.

4. No TXU engineering costs are included. TXU or TXU’s subcontractor would

be responsible for reviewing the EPC contractor’s detailed design calculations, construction drawings, as-built drawings, and other project documentation.

5. No TXU field construction inspection costs are included. TXU or TXU’s

subcontractor should perform construction inspection to insure that the underground transmission line is constructed in compliance with the project specifications.


6. The costs do not include the costs to solicit and evaluate EPC proposals for the lines.

7. The costs do not include the cost of performance or warranty bonds. 8. The costs do not include the cost of decommissioning of the existing overhead

line. Costs for construction of the underground transmission line include the following:

1. Materials required to construct the underground transmission line including vaults, riser poles, and 138-kV surge arresters for each of the cable terminations.

2. Civil construction costs required to excavate and backfill trenches and pits for

the manholes or splice pits. 3. Material and equipment for installing steel casings and PVC conduits at major

road crossings. 4. Equipment and labor for pulling the transmission cables. 5. Equipment and personnel for splicing and termination of the transmission

cables. 6. Field construction supervision for cable installation and civil construction work. 7. Performing field and laboratory soil thermal resistivity survey. 8. Cost of performing post-construction commissioning tests. 9. As-built plan and profile drawings of the underground lines. 10. Local sales and federal import taxes. 11. Shipping charges for material to the construction site. Table 4-4 contains a summary of the opinion of probable costs.

Component Existing Right-of-Way City Streets Material $4,487,000 $3,937,000 Civil Works $9,616,000 $6,077,000 Engineering $603,000 $432,000 Project Management, Inspection $648,000 $648,000 Miscellaneous (Taxes, etc.) $1,053,000 $771,000 Totals $16,424,000 $11,865,000

Table 4-4 - Summary of Underground Transmission Opinion of Probable Costs


OPINION OF PROBABLE COSTS FOR GREENVILLE - LOMO ALTO138 KV XLPE UG1 ALTERNATIVE 138 kV XLPE Cable Circuits With 1750 kcmil Segmental Copper Conductor XLPE Cables

1 ROW Prep./Service Roads - 14,260 8 114,080 114,0802 Trench Excavation, Streets (ft) 1,854 0 0 1,854 120 222,456 222,4563 Trench Excavation, Unpaved (ft) 200 200 50 9,982 9,9824 Spoil Disposal (cu.yd.) 2,377 10 23,767 23,7675 Construct Duct Bank (tr.ft.) 14,260 24 342,240 14,260 32 456,320 798,5606 Trench Shoring (tr.ft.) 14,260 14,260 30 427,800 427,8007 Fluidized Thermal Backfill (cu.yd.) 2,377 75 178,250 2,377 10 23,767 202,0178 Paving Repair (sq.ft.) 3,708 10 37,076 3,708 8 29,661 66,7379 Horizontal Directional Drilling (ft) 12,207 38 463,849 12,207 400 4,882,624 5,346,473

10 Pipe Jacking and Boring (ft) 250 48 12,000 250 625 156,250 168,25011 Trench Steel Plating (tr.ft.) 1,854 0 0 1,854 10 18,538 18,53812 Splice Vault (ea.) 7 42,000 294,000 7 20,000 140,000 434,00013 138 kV XLPE 1750 kcmil cable (ft.) 43,819 45 1,971,864 1,971,86414 Ground continuity conductor (ft) 14,260 2.5 35,650 8 2,000 16,000 51,65015 Duct Mandrel Testing 25 4,000 100,000 100,000

16 Cable Installation (section pulls) 24 8,000 192,000 192,00017 Ground conductor installation (sections) 8 2,000 16,000 16,00018 138 kV terminations (ea.) 6 8,000 48,000 6 8,000 48,000 96,00019 Manufacturer's field supervisor (week) 12 7,000 84,000 84,00020 Splice and termination special tools (lot) 1 25,000 25,000 25,00021 138 kV, 1-phase splices (ea.) 21 9,000 189,000 21 9,000 189,000 378,000

22 Cross-Bonding Link Boxes 5 8,140 37,987 5 3,000 14,000 51,98723 3-Ph Grounding Link Boxes 3 6,270 20,900 3 1,000 3,333 24,23324 Cable Clamps 245 130 31,850 245 100 24,500 56,35025 Upaved ROW restoration (sq.ft.) 399 1 399 399 1 399 79926 Cable Termination Structures 2 52,000 104,000 2 6,000 12,000 116,00027 Mob./Demobi. Cable Contractor (ea.) 2 30,000 60,000 60,00028 Mobile Office/Storage Areas 75,00029 Traffic Control lot 75,000 85,00030 Security (man-days) 360 300 108,000 108,00031 Test & Energization (ea) Lump Amt. 20,000 20,000 20,00032 Emergency repair parts (lot) 1 109,500 109,500 0 109,500

33 Subtotal $3,901,565 $7,467,477 $11,454,042

34 Specification Preparation $35,000 $35,00035 Detailed Engineering (ea.) $568,452 $568,45236 Surveys (lot) $250,000 $250,00037 Soil Survey $33,000 $33,000

38 Construction Supervision (days) 360 800 $288,000 $288,00039 Project Management 300 1200 $360,000 $360,000

40 Field Construction Inspection 360 800 $288,000 $288,00041 Construction Contingency & Profit (20%) $1,493,495 $1,493,49542 Material Contingency & Profit (15%) $585,235 $585,235

43 S u b t o t a l s $4,486,800 $10,783,424 44 S a l e s T a x 7% $1,068,916

T o t a l C o s t $16,424,140

Date 5/7/06 MVA Rating 239

Route Length (ft)

14,260 Circuits

TrenchLength (ft) 14,260 Cables Per Phase

Cables Per Trench 3 Manholes/Ckt.

Nominal Cable Length (ft) 42,780 3-Ph Terminations

1 1 7 2

Unit Labor Labor Total

Unit Item Description Qnty. Material Material Qnty.


OPINION OF PROBABLE COSTS FOR GREENVILLE - LOMO ALTO138 KV XLPE UG2 ALTERNATIVE 138 kV XLPE Cable Circuits With 1750 kcmil Copper Conductor XLPE Cables

1 ROW Preparation - 14,260 8 114,080 114,0802 Trench Excavation, Streets (ft) 12,834 0 0 12,834 120 1,540,080 1,540,0803 Deep Trench Excavation (ft) 1,426 1,426 312 444,912 444,9124 Spoil Disposal (cu.yd.) 2,377 12 28,520 28,5205 Construct Duct Bank (tr.ft.) 14,260 24 342,240 14,260 32 456,320 798,5606 Trench Shoring (tr.ft.) 14,260 14,260 30 427,800 427,8007 Fluidized Thermal Backfill (cu.yd.) 2,377 75 178,250 2,377 10 23,767 202,0178 Paving Repair (sq.ft.) 30,897 8 247,173 30,897 3 92,690 339,8639 Pipe Jacking and Boring (ft) 250 48 12,000 250 625 156,250 168,250

10 Trench Steel Plating (tr.ft.) 12,834 0 0 12,834 10 128,340 128,34011 Splice Vault (ea.) 7 42,000 294,000 7 20,000 140,000 434,00012 138 kV XLPE 1750 kcmil cable (ft.) 43,819 40 1,752,768 1,752,76813 Ground continuity conductor (ft) 14,260 2.5 35,650 8 2,000 16,000 51,65014 Duct Mandrell Tests 25 4,000 100,000 100,00015 Cable Installation (section pulls) 24 8,000 192,000 192,00016 Ground conductor installation (sections) 8 2,000 16,000 16,00017 138 kV terminations (ea.) 6 8,000 48,000 6 8,000 48,000 96,00018 Manufacturer's field supervisor (week) 12 7,000 84,000 84,00019 Splice and termination special tools (lot) 1 25,000 25,000 25,00020 138 kV, 1-phase splices (ea.) 21 9,000 189,000 21 9,000 189,000 378,00021 Cross-Bonding Link Boxes 5 8,140 37,987 5 3,000 14,000 51,98722 3-Ph Grounding Link Boxes 3 6,270 20,900 3 1,000 3,333 24,23323 Cable Clamps 245 130 31,850 245 100 24,500 56,35024 Upaved ROW restoration (sq.ft.) 2,852 1 2,852 2,852 1 2,852 5,70425 Cable Termination Structures 2 52,000 104,000 2 6,000 12,000 116,00026 Mob./Demobi. Cable Contractor (ea.) 2 30,000 60,000 60,00027 Mobile Office/Storage Areas 85,00028 Traffic Control lot 75,000 75,00029 Security (man-days) 360 300 108,000 108,00030 Test & Energization (ea) Lump Amt. 20,000 20,000 20,00031 Emergency repair parts (lot) 1 102,000 102,000 0 102,000

32 Subtotal $3,423,670 $4,517,444 $8,026,114

33 Specification Preparation $35,000 $35,00034 Detailed Engineering (ea.) $397,056 $397,05635 Surveys (lot) $250,000 $250,00036 Soil Survey $33,000 $33,000

37 Construction Supervision (days) 360 800 $288,000 $288,00038 Project Management 300 1200 $360,000 $360,000

39 Field Construction Inspection 360 800 $288,000 $288,00040 Construction Contingency & Profit (20%) $903,489 $903,48941 Material Contingency & Profit (15%) $513,551 $513,55142 S u b t o t a l s $3,937,221 $7,071,989

43 S a l e s T a x 7% $770,645 T o t a l C o s t $11,864,854

Date 5/7/06 MVA Rating 239

Route Length (ft)

14,260 Circuits

TrenchLength (ft) 14,260 Cables Per Phase

Cables Per Trench 3 Manholes/Ckt.

Nominal Cable Length (ft) 42,780 3-Ph Terminations

1 1 7 2

Unit Labor Labor Total

Unit Item Description Qnty. Material Material Qnty.

SECTION 5

CONVERSION OF ALLEY AERIAL SERVICES TO UNDERGROUND


CONVERSION OF ALLEY ARIEL SERVICES TO UNDERGROUND INTRODUCTION

The City of University Park, Texas is considering the feasibility of converting certain overhead utilities

(electric distribution, telephone, and cable TV) that serve residential customers from the alleys behind the

residences. This could be in conjunction with the City’s “mile-per-year project”, which is an on-going

effort to replace existing underground utility lines (gas, water, and sewer) below the alleys throughout the

City. This Study is based on the premise that the placement of the aerial services underground will occur

concurrently with the reconstruction of the existing underground utilities.

This Study takes into consideration the various service provider’s standards and requirements for placing

their particular utility services underground. Any additional right-of-way easements required will be

addressed. In order to display a proposed layout of the underground services, a typical City block was

selected, which is the block bordered in the north and south by Stanford and Amherst Streets and the east

and west by Hillside Avenue and Airline Road. Opinions of probable cost are developed for the block

area and can be extrapolated for area lengths of more than one block. Two versions of undergrounding

these utilities were considered, the first with all utilities placed underground in the alley and the second

with the electric, cable, and telephone served from primarily the front of each lot. The latter would not

require additional right-of-way in the alley area.

EXISTING RIGHT-OF-WAY

The City’s alleys have utility rights-of-way of various widths with the majority being either 10-feet or 15-

feet wide. The selected block has a 10-foot width. The current underground utilities placed within these

rights-of-way are sewer, water, and gas. The existing overhead utilities are supported by wood poles

which are also located within the rights-of-way. See Figures 5-1 and 5-2 which show a cross section of

the utilities and right-of-way for a 10-foot and 15-foot width, respectively. Figures 5-2 and 5-3 show the

cross section of the utilities plus the sanitary sewer service conditions.


UTILITY REQUIREMENTS

Several meetings and discussions were held with the various entities that would be involved in an alley

underground project. The following indicates each utility and some of the salient points of their

requirements:

1. Sewer - City of University Park: a. Typically an 8-inch PVC line placed at a depth of 9 to 11 feet below grade. b. Line will be tapped for each residence, sweeping upward toward each residence

which requires a minimum of 12-inch clearance to other pipes or objects. 2. Water - City of University Park: a. Typically an 8-inch PVC line placed at a depth of 42 inches below grade. b. Line will be tapped for service lines to each residence’s water meter. 3. Gas - Atmos Energy: a. Typically a 2-inch PVC line placed 2 to 3 feet below grade. b. Line will be tapped with 3/4-inch service line to each residence’s gas meter. 4. Electrical Distribution - TXU Electric Delivery: a. The primary (15-kV), three-phase distribution circuit is to be placed in the street in

a 2-by-2, 6-inch conduit, concrete-encased duct bank. Cable size and type is 1,000 kcmil EPR with concentric neutral.

b. A four-way or three-way manhole (approximately 12 feet by 12 feet) will be

placed in the street every block and will connect the primary duct bank in at least two directions, plus the connection to pad-mounted switchgear.

c. The pad-mounted switchgear unit (enclosed in a metal or fiberglass cabinet

approximately 6-feet wide by 6-feet long by 5-feet high) placed at each block will connect the primary three-phase circuit to a single-phase (15-kV) circuit that will be fed to a series of pad-mounted transformers. The single circuit line (one 1/0 aluminum, XLPE cable in a 4-inch PVC conduit) will loop through each transformer in the alley and connect to the adjacent block’s switchgear. (See example in Figure 5-5.)


Figure 5.5

d. Each transformer (assumed to be a 75-kVA unit) will typically serve six residences. See example in Figure 5-6 which includes (left to right) a cable TV pedestal, pad-mounted transformer, and telephone pedestal. The 240/120-volt service drops to each residence will be a three-wire circuit in a PVC conduit. The transformers have been located so each unit can provide service to two residence meters and a circuit to a secondary pedestal which will in turn serve four residences. See Figure 5-7 which shows a cable TV pedestal on the left and an electric secondary pedestal on the right.

Figure 5-6


Figure 5.7 e. Each pad-mounted transformer will require a footprint area approximately 5-feet

deep and 4-feet wide. Working and ventilating clearance to objects is 5 feet with 10 feet required for hot-stick maintenance for the front side. The transformer orientation would need to have this side facing the alley.

5. Telephone - AT&T: a. The telephone system for residences will be sourced from a large 1,200-pair cable

or larger which will be connected to a 600-pair cable that will run the length of the alleys. This connection will be made in a handhole (4-feet by 4-feet wide by 8-feet by 4-feet deep) or a traffic bearing manhole (6-feet wide by 8-feet long by 6-feet deep) located near the alley entrance, one per block.

b. The 600-pair cable will be installed in a 4-inch conduit the length of the alley in

each block. c. A 100-pair cable will also connect in the manhole/handhole and connect to

telephone pedestals by looping in and out for the length of the block. Each pedestal will provide service to four residences.

6. Cable TV - Charter Communications: a. The cable TV system for residences will be sourced from a main fiber optic feeder

which will be connected to a trunk fiber optic line that runs the length of the alley and connects to two amplifier pedestals per block (approximately 600 feet apart).

b. Coaxial cable will then connect to the cable pedestals; each will serve four

residences. c. The trunk fiber-optic cable and coaxial cables to the pedestals will be installed in a

4-inch PVC conduit which will have three, 1-1/4-inch subducts contained in the 4-inch conduits.


CONSTRUCTION METHODS

As described above, almost all of the existing aerial facilities would need to be installed under the alley

with the exception of the electrical-distribution, primary, three-phase feeders. Figures 5-1 and 5-2 show

the cross section of required right-of-way and clearances for all the utilities. The construction concept is

that during the replacement of the existing underground utilities (the pipes), the existing overhead utilities

(the wires) would be placed underground utilizing joint-trench participation among the various entities.

Figures 5-3 and 5-4 show the cross section of the proposed underground with the existing sanitary sewer

service for individual residences. Two of these service connections occur for every lot width

(approximately every 50 feet). Likewise, service connections for water and gas will have service

connections that rise from the primary line for each residence’s meter (approximately every 50 feet).

One of the 4-inch conduits for the telephone lines will continue underground for the length of the block.

The other 4-inch conduit would need to rise up to loop into each telephone service pedestal and then

return under ground. These telephone conduit risers would be located approximately every 100 feet.

The cable TV 4-inch conduit which would contain three subducts would also need to turn up and loop

through each amplifier and cable TV service pedestal. These conduit risers would also need to be located

approximately every 100 feet.

Figure 5-8 shows the electric distribution, cable TV, and telephone services emanating from the alley. As

stated earlier, this layout requires additional rights-of-way and easements in the alley and residents'

backyards.

Figure 5-9 shows an alternative to the alley construction by placing the electric-distribution, pad-mounted

transformers and pedestals, and the cable TV and telephone pedestals at the front of the residential lots.

This method would alleviate the need for additional rights-of-way in the backyards, but would require

additional easements in the front yards and along lot lines between houses to be able to route the service

cables to the existing residential connections at the rear of the houses.


ADDITIONAL EASEMENTS AND RIGHT-OF-WAY REQUIREMENTS

As shown on Figures 5-1 through 5-4, to allow for the placement of the wire utilities underground,

additional rights-of-way would be required to allow for these additions to meet the necessary clearance

requirements for construction and maintenance. The figures show that a width of 20 feet would be

required. Additional rights-of-way will be required along the line route in the alley between Stanford and

Amherst for 11 blocks and in the alley between Daniel and University for two blocks. Approximately

92,400 square feet of additional rights-of-way was calculated for the alleys.

With the additional rights-of-way available, most of the pad-mounted equipment, including telephone

pedestals, cable amplifiers, cable pedestals, and electrical-distribution secondary pedestals, would need to

be located in this area outside the paved-alley driving surface. Additional easements may be required for

placement of the larger pad-mounted electrical equipment, including the pad-mounted switchgear cabinets

and the pad-mounted transformers. The transformers require a much larger area than the service

pedestals. As indicated earlier in the Study, the footprint size plus the operating clearance distances, an

area of approximately 14-feet wide and 10-feet deep, would be required for each transformer. Additional

rights-of-way required for the transformers and pad-mounted switchgear would be approximately 780

square feet.

OPINION OF PROBABLE COST

An opinion of probable cost was developed for the material and installation of the aerial utilities

underground in conjunction with replacing the existing underground sanitary sewer, gas, and water

utilities and placing underground in the alley. These costs include only the incremental costs for the

electrical, cable, and telephone. These costs were developed based on the single block illustrated on

Figure 5-8. The cost per block is approximately $832,000. The cost for the portion of the utilities

currently under the Greenville - Loma Alto transmission line is approximately equivalent to 10 blocks,

thus a cost of approximately $8,320,000. The cost for purchasing additional rights-of-way for the alley

underground construction plus pad-mounted equipment requirements along the line route is

approximately $6,036,000, based on a $60-per-square-foot cost.


Figure 5-9 shows a layout with the service pedestals and transformers located at the front of the lots. The

cost per block would be approximately $900,000 due to the longer feeder cable and service drops. The

total line route cost would be approximately $9,000,000. This would not require additional rights-of-way

in the alley, but would require more in the front of the lots and along lot lines between houses. The

approximate cost would be $12,829,200 again based on a $60-per-square-foot cost.

Opinion of Probable Cost 5/22/2006Front Sheet

Job Name: University Park, TX UG Util / Alley Rev. 0 Estimator: Andy HaunStart date: 01/01/07 End date: 04/01/07 Date: 05/22/06Duration: 13 Weeks Location: University Park, TXBid Date Expires: 3-Sep-06

Labor: Bidders:First Shift: Regular rate 4,765 hrs @ $53.85 $256,618 Overtime rate (diff) 0% 0 hrs @ $18.45 $0 Premium rate (diff) 5% 238 hrs @ $36.89 $8,780

Subtotal: $265,398

Labor Efficiency $265,398 @ 10.00% $26,540Subtotal: $291,938

Supervision 5.00% $14,597Subtotal: $306,535

Rate Increase 100% $306,535 @ 3.00% $9,196Subtotal: $315,731

Total Labor Cost $315,731

Material $216,662Escalation ($3.00 Copper) $216,662 @ 10.0% $21,666

Subtotal: $238,328Sales tax 6.9% $16,445

Subtotal: $254,773MBE Participation $0 @ 2.0% $0

Subtotal: $254,773Total Material Cost $254,773 $1.352

Job Expenses:Tools/Equipment $6,314Site Superintendent $37,866Documentation $0Safety $2,350

Subtotal: $46,530 % of L&MTotal Job Expense $46,530 8.16%

Sub Total Job Cost $617,034

Contractor Overhead & Profit 15.0% $92,555Engineering 10.0% $61,703Estimating Contingency 10.0% $61,703Subcontractors $0

$0Subtotal: $0

Total Subcontractors Markup 10.0% $0Bonding Subtotal: $0 0.72% $0

TOTAL: $832,995Distribution Rates:Labor: 4765 hrs @ $113.339 Distr rate $540,068Material: $216,662 @ $1.352 Distr rate $292,927Expenses $46,530 @ $1.150 Distr rate $53,510Subcontractors: $0 @ $1.100 Distr rate $0

TOTAL: $832,995Base: $832,995Difference: $0

5.6% Per Year

File: UnivParkUGUtilAlley0506 / Front Sheet5/22/2006 3:36 PM

Opinion of Probable CostBasic Field Costs

Job Name: University Park, TX UG Util / Alley Rev. 0 5/22/2006Location: University Park, TX

Projected Start End01/01/07 04/01/07 90

6413

RATES:Average manpower: 4,765 hrs + 10% 5,242 hrs (incl lost time)

Single shift: 8 hrs per day 10 men1-Shift 10 Hr 10 hrs per day 10 menDouble shift: 20 hrs per day 4 men

Present wage rates: Expire: JW FM GFFIRST SHIFT: Straight time: $53.854 $57.789 $59.764LU#124 - MO Overtime: $72.300 $78.035 $80.911Kansas City, MO Premium: $90.745 $98.282 $102.058SECOND SHIFT: Journeyman: $0.000 $0.000 $0.000

Differential to ST: ($53.854) ($53.854) ($53.854)

Supt. Rate: Regular rate: 40 hrs @ $59.764 $2,390.56LU#124 - MO Overtime rate: 5 hrs @ $80.911 $404.56Kansas City, MO Premium rate: 0 hrs @ $102.058 $0.00KC GF Rate Weekly Subtotal: $2,795.12

Second shift: 0% @ 7.47% $0.00Weekly Subtotal: $2,795.12

Average cost: 45 hrs work week: $62.11 (per hour)

JOB EXPENSES: % of Labor & Material: 8.16%

Administrative Costs: Supt living: 0 wks @ $450 $0Supt wages: 13 wks @ $2,795 $35,937Supt truck: 13 wks @ $150 $1,929Added supt: 0 wks @ $2,795 $0Added truck: 0 wks @ $150 $0Office trailer: 0 mo @ $500 $0Office utilities: 0 mo @ $200 $0PM travel: 0 trips $300 $0 $37,866

Documentation: Engineering: 0 hrs @ $65 $0Drafting: 0 hrs @ $45 $0 $0

Safety Costs: Safety equip: 10 men@ $135 $1,350Drug Testing 10 men@ $50 $500 (1.5 hrs)Safety Meeting 10 hrs @ $50 $500 $2,350

Miscellaneous: Expendables 1.0% labor $315,731 $3,157Small tools 1.0% labor $315,731 $3,157Lift delivery 0 @ $125.00 $065' Genie 0 mo@ $2,050.00 $045' Genie 0 mo@ $1,200.00 $0 $6,314

TOTAL EXPENSES: $46,530

3-Sep-06

Cal. daysWk. daysWeeks

File: UnivParkUGUtilAlley0506 / Expenses5/22/2006 3:37 PM

Opinion of Probable Cost 05/22/06Distribution Sheet

Job: University Park, TX UG Util / Alley Rev. 0 Labor $113.339City: University Park, TX Material $1.352

Subs $1.100PROPOSAL BREAKDOWN:

Item Description Labor MaterialHrs Sell Cost Sell TOTAL

1 15kV Power 921 $104,372 $130,194 $176,022 $280,3942 120/240V Power 1,266 $143,435 $31,587 $42,706 $186,1413 Telephone 1,491 $169,007 $27,671 $37,411 $206,4184 Cable TV 847 $96,053 $25,210 $34,085 $130,1385 Electrical Power and Comm System Startup 240 $27,201 $2,000 $2,704 $29,9056 Gas 0 $0 $0 $0 $07 Water 0 $0 $0 $0 $08 Sanitary Sewer 0 $0 $0 $0 $09 Pavement Removal and Replacement 0 $0 $0 $0 $010 0 0 $0 $0 $0 $011 0 0 $0 $0 $0 $012 0 0 $0 $0 $0 $013 0 0 $0 $0 $0 $014 0 0 $0 $0 $0 $015 0 0 $0 $0 $0 $016 0 0 $0 $0 $0 $0

Grand Totals 4,765 $540,068 $216,662 $292,928 $832,996

Front sheet totals: 4,765 $540,068 $216,662 $292,927 $832,995Difference: 0 $0 $0 ($1) ($1)

File: UnivParkUGUtilAlley0506 / Distribution5/22/2006 3:37 PM

Sega, Inc. 05/22/06Opinion of Probable CostTakeoff SheetsUniversity Park, TX UG Util / Alley Rev. 0

1 Sheet: 15kV Power

Labor Labor Material MaterialUnit Extension Unit Extension

Ductbank at Lot Front 1,200 Excav/Bkfil Unit Labor & Equip at 50' per hour 2.00 c 24.00 $75.00 c $900.002,400 6"PVC 6.75 c 162.00 $194.00 c $4,656.00

120 - 6" PVC Coupling 0.35 e 42.00 $8.00 e $960.00240 - 6" PVC Chairs 0.18 e 43.20 $1.40 e $336.00

4 - 6" Elbows GRS 3.75 e 15.00 $250.00 e $1,000.001,200 Concrete per ft 2'x2' Ductbank at $75 per CY e $11.11 e $13,332.00

1 Prefabricated Manhole 16.00 e 16.00 $5,000.00 e $5,000.00Extend Ductbank to Padmt Sw

120 Excav/Bkfil Unit Labor & Equip at 50' per hour 2.00 c 2.40 $75.00 c $90.00120 6"PVC 6.75 c 8.10 $194.00 c $232.80

6 - 6" PVC Coupling 0.35 e 2.10 $8.00 e $48.0012 - 6" PVC Chairs 0.18 e 2.16 $1.40 e $16.804 - 6" Elbows GRS 3.75 e 15.00 $250.00 e $1,000.00

120 Concrete per ft 2'x2' Ductbank at $75 per CY e $11.11 e $1,333.201 S&C PMH-Series 15kV Padmt Switch Complete 32.00 e 32.00 $16,000.00 e $16,000.00

Ductbank for Alley Distribution 80 Excav/Bkfil Unit Labor & Equip at 50' per hour 2.00 c 1.60 $75.00 c $60.00

120 4" PVC 4.50 c 5.40 $159.59 c $191.516 - 4" PVC Couplings 0.19 e 1.14 $5.00 e $30.00

12 - 4" PVC Chairs 0.13 e 1.56 $1.00 e $12.004 - 4" Field Bends 1.20 e 4.80 $5.00 e $20.00

1,280 Concrete per ft 1'x1' Ductbank at $75 per CY e $5.56 e $7,116.80Feeder Cable & Terminations

4,092 15kV 1000MCM Al URD EPR/CPE 1/3N 80.00 m 327.36 $13,900.00 m $56,878.801,500 15kV 1/0AWG Al URD EPR/CPE 1N 25.00 m 37.50 $3,900.00 m $5,850.00

8 #1000 15KV Termination Stress Cone 6.00 e 48.00 $100.00 e $800.002 #1/0 15KV Termination Stress Cone 2.50 e 5.00 $85.00 e $170.00

Transformers including C. Riser & 15kV Term 8 75kVA 15kV:120/240 6.00 e 48.00 $1,500.00 e $12,000.008 - 10' x3/4'' Ground Rod 1.50 e 12.00 $18.00 e $144.00

48 4" PVC 4.50 c 2.16 $159.59 c $76.6016 - 4" Field Bends 1.20 e 19.20 $5.00 e $80.00

128 15kV 1/0AWG Al URD EPR/CPE 1N 25.00 m 3.20 $3,900.00 m $499.2016 #1/0 15KV Termination Stress Cone 2.50 e 40.00 $85.00 e $1,360.00

Note: Excludes Concrete/Ashpalt Cut/Patch

TOTALS: 920.88 $130,194

PerPerQuantity Description

Project: UnivParkUGUtilAlley0506 / Takeoff5/22/2006 3:37 PMPage 1 of 6

2 Sheet: 120/240V Power


120/240 Extensions to Pedestals (8 avg. 60') 8 120/240V Distribution Pedestal 8.00 e 64.00 $75.00 e $600.00

480 4" PVC 4.50 c 21.60 $159.59 c $766.0316 - 4" Field Bends 1.20 e 19.20 $5.00 e $80.00

1,920 500MCM XHHW 44.00 m 84.48 $3,443.29 m $6,611.1248 500MCM termination 0.70 e 33.60 $22.39 e $1,074.72

640 #4 XHHW 14.00 m 8.96 $381.57 m $244.2016 #4 termination 0.35 e 5.60 $3.00 e $48.00

(Share Alley Excav/Bkfil w/ 15kV Ductbank) Service Drops (46 avg. 60')

2,760 1 1/2 " PVC 2.75 c 75.90 $50.09 c $1,382.48184 - 1 1/2" Field Bends 1.15 e 211.60 $5.00 e $920.0046 - 1 1/2" Male Adaptors 0.20 e 9.20 $2.50 e $115.00

368 1 1/2" GRC 12.00 c 44.16 $344.13 c $1,266.4046 - 1 1/2" Myers hubs 0.50 e 23.00 $3.45 e $158.7092 - 1 1/2" Conduit supports 0.18 e 16.56 $4.30 e $395.60

11,040 #3/0 XHHW 26.00 m 287.04 $1,188.71 m $13,123.36276 #3/0 termination 0.90 e 248.40 $8.17 e $2,254.92

3,680 #6 XHHW 13.00 m 47.84 $249.01 m $916.3692 #6 termination 0.30 e 27.60 $2.72 e $250.24

1,840 Excav/Bkfil Unit Labor & Equip at 50' per hour 2.00 c 36.80 $75.00 c $1,380.00(Use Backhoe to Share Excav/Bkfil w/ T & C)

Note: Excludes Concrete/Ashpalt Cut/Patch

TOTALS: 1265.54 $31,587



3 Sheet: Telephone


Trunk Line in Alley 2 Prefabricated Pavement-rated HandHole 8.00 e 16.00 $2,000.00 e $4,000.00

12 Telephone Distribution Pedestal 4.00 e 48.00 $150.00 e $1,800.002,600 4" PVC 4.50 c 117.00 $159.59 c $4,149.34

16 - 4" Field Bends 1.20 e 19.20 $5.00 e $80.0028 - 4" Male Adaptors 0.35 e 9.80 $4.00 e $112.00

1,300 Telephone 600 pr Cable 40.00 m 52.00 $6,000.00 m $7,800.001,300 Telephone 100 pr Cable 25.00 m 32.50 $3,000.00 m $3,900.00

300 1PR #20 Termination (one end ) 2.50 e 750.00 $0.75 e $225.00Service Drops (46 avg. 60')

2,760 1" PVC 2.00 c 55.20 $29.57 c $816.13184 - 1" Field Bends 1.00 e 184.00 $5.00 e $920.0046 - 1" Male Adaptors 0.15 e 6.90 $2.00 e $92.00

368 1" GRC 8.00 c 29.44 $203.21 c $747.8146 - 1" Myers hubs 0.40 e 18.40 $2.54 e $116.8492 - 1" Conduit supports 0.12 e 11.04 $2.25 e $207.00

2,760 Tray Cable FREP/CPE #16 Shld 4PR 18.00 m 49.68 $880.00 m $2,428.8092 4PR #16 Termination (one end ) 1.00 e 92.00 $3.00 e $276.00

Note: Excav/Bkfil incl with Elec Power

TOTALS: 1491.16 $27,671



4 Sheet: Cable TV


Trunk Line in Alley 2 Prefabricated Pavement-rated HandHole 8.00 e 16.00 $2,000.00 e $4,000.00

10 Cable Distribution Pedestal 4.00 e 40.00 $150.00 e $1,500.002 Cable Distribution Pedestal / Amplifier 6.00 e 12.00 $2,500.00 e $5,000.00

1,300 4" PVC 4.50 c 58.50 $159.59 c $2,074.678 - 4" Field Bends 1.20 e 9.60 $5.00 e $40.00

14 - 4" Male Adaptors 0.35 e 4.90 $4.00 e $56.001,300 Thick-net Coax Cable 25.00 m 32.50 $4,000.00 m $5,200.00

28 Coaxial Cable 59/U Terminations 2.50 e 70.00 $2.50 e $70.00Service Drops (46 avg. 60')

2,760 1" PVC 2.00 c 55.20 $29.57 c $816.13184 - 1" Field Bends 1.00 e 184.00 $5.00 e $920.0046 - 1" Male Adaptors 0.15 e 6.90 $2.00 e $92.00

368 1" GRC 8.00 c 29.44 $203.21 c $747.8146 - 1" Myers hubs 0.40 e 18.40 $2.54 e $116.8492 - 1" Conduit supports 0.12 e 11.04 $2.25 e $207.00

2,760 Thin-net Coax Cable 25.00 m 69.00 $1,500.00 m $4,140.0092 Coaxial Cable 59/U Terminations 2.50 e 230.00 $2.50 e $230.00

Note: Excav/Bkfil incl with Elec Power

TOTALS: 847.48 $25,210

5 Sheet: Electrical Power and Comm System Startup


1 Power and Signal System Testing 160.00 e 160.00 $2,000.00 e $2,000.001 Coordinate Outages and Changeovers 80.00 e 80.00 e

TOTALS: 240.00 $2,000

PerPer

PerPer

Quantity Description

Quantity Description


6 Sheet: Gas


Distribution Line 1,300 Excav Unit Labor & Equip at 50' per hour 2.00 c 26.00 $75.00 c $975.001,300 Backfill Unit Labor & Equip at 100' per hour 1.00 c 13.00 $200.00 c $2,600.00

2 Connection to Existing Gas Distribution e $2,000.00 e $4,000.001,300 Gas Distribution Line, 2" PE e $3.37 e $4,381.00

Service Drops (46 avg. 60') 46 Tee Connection e $70.00 e $3,220.0046 Service Valve e $165.00 e $7,590.00

2,760 Gas Distribution Line, 1/2" PE e $2.29 e $6,320.4046 Connection to Existing Meter e $70.00 e $3,220.00

Note: Unit Costs from Means Bldg Cost Data

TOTALS:

7 Sheet: Water


Distribution Line 2 Connection to Existing Water Distribution e $1,000.00 e $2,000.001 Valve & Connection Lump Sum e $230.00 e $230.00

1,300 Water Distribution Line, 8" PVC e $17.58 e $22,854.00Service Drops (46 avg. 60')

46 Tee Connection e $195.00 e $8,970.002,760 Water Distribution Line, 1" PVC e $1.49 e $4,112.40

46 Connection to Existing Meter e $195.00 e $8,970.00

Note: Excav/Bkfil incl with Gas Distribution Note: Unit Costs from Means Bldg Cost Data

TOTALS:




8 Sheet: Sanitary Sewer


Distribution Line 2 Connection to Existing Line e $1,000.00 e $2,000.00

1,300 Sanitary Sewer Line, 8" PVC e $7.94 e $10,322.00Service Drops (46 avg. 60')

46 Connection to Line e $620.00 e $28,520.00

Note: Excav/Bkfil incl with Gas Distribution Note: Unit Costs from Means Bldg Cost Data

TOTALS:

9 Sheet: Pavement Removal and Replacement


1 Lump Sum Estimate for Alley e $50,000.00 e $50,000.001 Lump Sum for Misc. Sidewalks & Drives e $20,000.00 e $20,000.00

TOTALS:

Quantity Description Per Per

Quantity Description Per Per


Sega, Inc.Opinion of Probable CostDistribution

Job: University Park, TX UG Util / Alley Rev. 0City: University Park, TX

Cost Breakdown:Item Description Labor Material Total

1 15kV Power $280,3942 120/240V Power $186,1413 Telephone $206,4184 Cable TV $130,1385 Electrical Power and Comm System Startup $29,9056 Gas $07 Water $08 Sanitary Sewer $09 Pavement Removal and Replacement $010 0 $011 0 $012 0 $013 0 $014 0 $015 0 $0

Grand Totals $832,996

Note: Breakdowns include 15% O&P, 10% Engineering, and 10% Contingency

$104,372$143,435$169,007$96,053$27,201

$0$0$0$0$0$0$0$0$0$0

$540,068

$176,022$42,706$37,411$34,085$2,704

$0$0$0$0$0$0$0$0$0$0

$292,928

File: UnivParkUGUtilAlley0506 / Distribution5/22/2006 3:37 PM

SECTION 6

CONCLUSIONS


CONCLUSIONS Sections 3, 4, and 5 consider the various transmission and utility alternatives independently. The

following table summarizes various combinations of alternatives ranging from rebuilding the existing line

to the existing design parameters to placing transmission, distribution, and telecommunications utilities

underground.

Table 6-1Summary of Alternative Transmission and Distribution Options

Overhead Underground Obtain ROWOverhead Distribution Underground Distribution for Total

Transmission & Telecommunications Transmission & Telecommunications Underground Cost

Rebuild Line, Existing Configuration;Pole-for-Pole;125' Spans +/-

52' - 57' Above Ground


$4,499,800Rebuild Line, Vertical

Configuration;Skip-Span Construction;

250-Spans +/-;68' Above Ground


$3,552,284

Rebuild Line, Vertical Configuration;Pole-for-Pole;125' Spans +/-

63' Above Ground


$4,620,000

Rebuild Line, Delta Configuration;

Skip-Span Construction;250-Spans +/-;

61' Above Ground


$3,575,000

Rebuild Line, Vertical Configuration;250' Spans +/-;No Underbuilds;

50' Above Ground

Remove None PlaceUnderground in Alley Obtain ROW

$8,329,950 $6,036,000 $17,430,950Rebuild Line, Vertical

Configuration;250' Spans +/-;No Underbuilds;

50' Above Ground

Remove None Place Underground in Front of Lots Obtain ROW

$9,000,000 $12,830,000 $24,206,596

Remove Transmission;Leave Distribution

and Telecom

Leave in Place;Cut Tops off Poles;34' Above Ground

Install UndergroundTransmission None None

$11,800,000 $12,069,438


PlaceUnderground in Alley Obtain ROW

$11,800,000 $8,329,950 $6,036,000 $26,613,775


Place Underground in Front of Lots Obtain ROW

$11,800,000 $9,000,000 $12,830,000 $34,667,000

Alternative 7A$1,037,000

Alternative 1

$4,499,800

Alternative 4

$3,575,000

$3,552,284

Alternative 7

Alternative 2

Alternative 3

$447,825

$4,620,000

$2,376,596

Alternative 5

Alternative 6

Alternative 5A

$3,065,000

$269,438

SECTION 3 OVERHEAD TRANSMISSION ALTERNATIVES 3-1 SECTION 4

Documents

Transcript of SECTION 3 OVERHEAD TRANSMISSION ALTERNATIVES 3-1 SECTION 4