Dlid Proj Rpt

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PROJECT REPORT

FOR THE

DELTA LAKE IRRIGATION DISTRICTWATER CONSERVATION PROJECT

PREPARED FOR:

DELTA LAKE IRRIGATION DISTRICT

ROUTE 1, BOX 225, EDCOUCH, TEXAS 78538

UNDER THE AUSPICES OF:

TEXAS WATER DEVELOPMENT BOARD and

TEXAS STATE ENERGY CONSERVATION OFFICE

TWDB Contract No. G18900

PREPARED BY:AXIOM-BLAIR ENGINEERING

2711 WEST ANDERSON LANE, SUITE 210

AUSTIN, TEXAS 78757

October 27, 2003


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Delta Lake Irrigation District PROJECT REPORT

TABLE OF CONTENTS

1 EXECUTIVE SUMMARY..........................................................................................1

2 INTRODUCTION........................................................................................................ 6

3 DISTRICT INFORMATION.......................................................................................6

4 DISTRICT FACILITIES AND WATER DELIVERY SYSTEM DESCRIPTION ... 7

5 DISTRICT WATER SUPPLY AND DEMAND ASSESSMENT.............................. 7

6 DISTRICTS CONSERVATION COMMITMENT...................................................8

7 PROPOSED PROJECT DESCRIPTION .................................................................... 9

7.1 Reservoir Renovation Project ...............................................................................9

7.2 Seepage Recovery Pilot Project..........................................................................11

7.3 Telemetry and Flow Measurement Project.........................................................12

7.4 Canal Rehabilitation Project ...............................................................................158 PROJECT BUDGET..................................................................................................17

9 DETERMINATION OF WATER AND ENERGY CONSERVED .........................18

9.1 Reservoir Renovation Project .............................................................................19



9.4 Canal Rehabilitation Project ...............................................................................21

10 ECONOMIC AND CONSERVATION ANALYSIS............................................22

10.1 Reservoir Renovation Project .............................................................................23



10.4 Canal Rehabilitation Project ...............................................................................24

10.5 Project Aggregate ...............................................................................................25

11 PROJECT SCHEDULE .........................................................................................28

12 REGULATORY COMPLIANCE DOCUMENTATION...................................... 28

13 SUPPLEMENTAL INFORMATION....................................................................31

13.1 Itemized Construction and O&M Cost ............................................................... 31

13.2 Construction Schedule........................................................................................37

13.3 Regulatory Compliance Documentation ........................................................... 38

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APPENDICIES

Appendix 1 TCEQ District Information Report

Appendix 2 District Boundary Map

Appendix 3 District Water Supply System Map

Appendix 4 Reservoir Renovation Project Site Location Map

Appendix 5 Seepage Recovery Pilot Project Site Location Map

Appendix 6 Telemetry and Flow Measurement Site Location Map

Appendix 7 Canal Rehabilitation Project Site Location Map

Appendix 8 Feasibility Study for the Seepage Recovery Pilot Project

Appendix 9 Pipeline Hydraulic Study

Appendix 10 Texas A&M University Report Canal Ponding Test Results

Appendix 11 Environmental Summary Report

Appendix 12 Construction Drawings for Reservoir Renovation Project

Appendix 13 Construction Drawings for Telemetry and Flow Measurement Sites Project

Appendix 14 Construction Drawings for Canal Rehabilitation Project Task A

Appendix 15 Federally Listed as Threatened and Endangered Species in Texas

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1 EXECUTIVE SUMMARY

The Project Applicant, Delta Lake Irrigation District (DLID or the District) was

established on June 22, 1914. The District is a political subdivision of the State of Texas,

organized under and by virtue of Article XVI, Section 59 of the Constitution of the Stateof Texas. It is operated under the statutes of Chapter 58 and Chapter 49, in part, of the

Texas Water Code. The District provides irrigation, drainage, and raw water supply

functions to 148.95 square miles of Hidalgo and Willacy Counties. The Delta Lake

Irrigation District has 182,966 acre-feet of authorized water rights and has the largest

amount of irrigated agriculture of the 28 irrigation districts in the Lower Rio Grande

Valley of Texas. The District is located within the boundaries of the Texas Water

Development Boards Rio Grande Regional Water Planning Group (Region M) and

includes the cities of Hargill, La Sara, Monte Alto and part of the City of Raymondville.

Figure 1 indicates the general project location. The Rio Grande is the only water source

for the Districts water supply system. All of the water diverted by the District, from the

Rio Grande, originates as surface water released by the International Boundary and Water

Commission from Falcon Reservoir. The District pumps water northward through a 32-

mile canal (Willacy Canal) originating at the Rio Grande and terminating at the southeast

corner of the East Reservoir of Delta Lake. The District water supply system consists of

250 miles of lined or partially lined canals, 42 miles of unlined canal and 122 miles of

unlined laterals. The District operates Delta Lake as a buffer for absorbing changes in

daily demand and mitigating the four-day travel time of water from Falcon Reservoir.

An assessment of the current and future water supplies and demands for Hidalgo andWillacy Counties are included in the Adopted Regional Water Plan (the Region M

Plan) published in January 2001 by the Texas Water Development Boards (TWDB) Rio

Grande Regional Water Planning Group (Region M). According to the Region M Plan,

the population in Hidalgo County is expected to more than double in the next 50 years;

while the population within Willacy County is expected to grow over 37 percent for the

same period. With the population growth, some of the land currently used for farming

and ranching will be converted to more urban use. As such, municipal water demand is

expected to more than double in Hidalgo County over the next 50 years, and increase

over 18 percent in Willacy County. This increase will be partially offset by an expected

29.3 percent decrease in irrigation demand in Hidalgo over the same period.

The Rio Grande is currently the only water source for the District and is expected to

remain the only source in the foreseeable future. Water in the Rio Grande from Fort

Quitman, Texas to the Gulf of Mexico is apportioned to the United States and Mexico

according to the 1944 Treaty. The apportionment is administrated by the International

Boundary and Water Commission (IBWC). Two international reservoirs, Amistad and

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Falcon, provide controlled storage capacity for over eight million acre-feet of water

owned by the United States and Mexico. According to the Region M Plan, it is estimated

that (by 2050) the firm yield of the Amistad-Falcon Reservoir System will decrease by

nearly 10 percent.

Water conservation by the District has become increasingly important due to an enduringdrought that has affected the lower Rio Grande Valley over the past several years. The

drought and the projected decrease in irrigation water supply has required the District to

place a greater emphasis on water conservation to ensure the delivery of water to the

customers they serve. The proposed Water Conservation Projectis proposed to continue

the Districts commitment to conserve water and energy.

The proposed Project is comprised of four separate components. The first component,

theReservoir Renovation Project, consists of building a 17,000 linear foot bypass canal

along the eastern edge of the eastern reservoir of Delta Lake. The second component, the

Seepage Recovery Pilot Project, consists of a feasibility study into the possibility of

collecting water that seeps from the Main Canal and pumping it back into the system.

The third component, the Telemetry and Flow Measurements Sites Project, includes the

installation of flow measurement devices at 20 water diversion points to monitor

deliveries and send this information, by telemetry, to the District headquarters. The

fourth component, the Canal Rehabilitation Project, consists of preparing construction

drawings for the replacement approximately 17,800 linear feet of open channel laterals

with new gasket joint PVC or RCP pipe and the preparation of a plan to replace an

additional 13.4 miles of open channel laterals with pipe.

Constructing the proposed bypass canal will reduce the seepage and evaporation losses

associated with transporting water through the East Reservoir of Delta Lake. Recovering

seepage water along the Willacy Canal will reduce the pumping costs by reducing the

elevation difference. The installation of the flow measurement devices will allow the

District to remotely measure the amount of water delivered from each of the 20 diversion

points to the different canal systems. By monitoring the information, the District will be

able to reduce the amount of excess water that is passed through the system. Replacing

open laterals with pipelines will reduce the evaporation and seepage losses, reduce on-

farm demand and reduce the quantity of water spilled. Reducing and/or recovering losses

due to evaporation, seepage and spills will allow more water to be available to eachcustomer in times of shortages.

Given that the Rio Grande is the Districts only anticipated water source, it is the

Districts goal to maximize efficiency by reducing excess pumping and seepage and

evaporation losses. Increased efficiency will postpone the need to develop new water

supplies. Since agricultural crops are a commodity, and their annual yield is dependent



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on many factors (including price, weather, supply and demand), it is impossible to

determine the exact date that the development of new water supplies may become a

necessity. Regardless of the water source, the Delta Lake Irrigation District is committed

to conserving both water and energy today and in the future.

The total project budget for the Water Conservation Project is estimated to be $7.12million. The budget includes funds from the Texas State Energy Conservation Office

through the Texas Water Development Board as well as contributions by the District.

Construction cost for the project (including project administration and contingencies) is

estimated to be $7.12 million.

An itemized construction cost estimate was prepared for each component of the Districts

Water Conservation Project. The estimated cost for theReservoir Renovation Projectis

$1,511,675. The estimated cost for the Seepage Recovery Pilot Projectis $669,640. The

estimated cost for the Telemetry and Flow Measurement Sites Projectis $794,530. The

estimated construction cost for the Canal Rehabilitation Projectis $4,031,496. Itemized

annual operation and maintenance (O&M) cost estimates were also prepared for each

component of the Districts Water Conservation Project. Annual O&M costs are

estimated to be $10,120 for theReservoir Renovation Project, $650 (exclusive of energy

costs) for the Seepage Recovery Pilot Project, $32,170 for the Telemetry and Flow

Measurement Sites Project and$3,360 for the Canal Rehabilitation Project.

In June 2001, the Bureau of Reclamation published a set of guidelines for evaluating

TWDB-SECO Water Conservation Projects1. The document describes the three

legislated operational efficiency criteria for evaluating water conservation projects:Annual acre-feet of water saved per dollar of construction costAnnual energy saved (BTUs) per dollar of construction cost, andAnnual economic savings per dollar of construction cost

The proposed project as a whole will result in:

Annual water savings of 13,808 acre feet,Annual energy savings of 2,530,387,224 BTUsEstimated construction cost of $7,120,000,Estimated annual operation and maintenance costs of $19,420,

The projected savings are:

0.0717 ac-ft per dollar of construction cost

1United States Department of the Interior Bureau of Reclamation, Guidelines For Preparing and

Reviewing Proposals for Water Conservation and Improvement Projects Under Public Law 106-576June, 2001



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12,950 BTUs per dollar of construction cost$0.344 per dollar of economic savings per dollar of construction cost.

The Operational Efficiency criteria may also be expressed in the inverse, representing the

amount in dollars expended, based on estimated construction cost, per unit of savings:

$13.94 per ac-ft

A more useful measure of the value of the cost per acre-foot of water saved is the dollars

of construction cost per present value of the quantity of water saved by the project. This

values equals:

$30.97 per acre foot

Once the Water Conservation Project receives funding, it is estimated that the time to

completion, including bidding and construction, will be approximately 2.5 years. The

construction contracts for each component of the project could both be in place in

approximately four months.

An Environmental Summary Report was prepared for the Project. Preparation of the

report utilized information from a wide variety of sources including the TCEQ, the U.S.

Census Bureau, the U.S. Fish and Wildlife Service, the Texas Parks and Wildlife

Department, the Texas Historical Commission, the National Weather Service, the U.S.

Soil Conservation Service, the Texas Department of Transportation and others.

Additional information was collected through field reconnaissance and interviews with

District personnel. The Environmental Summary Report was submitted to the Texas

Parks and Wildlife Department, Texas Historical Commission, U.S. Army Corps of

Engineers and the United States Fish and Wildlife Service for review.

The U.S. Army Corps of Engineers has determined that since the project sites do not

contain any areas subject to Section 10 of the Rivers and Harbors Act or Section 404 of

the Clean Water Act, a Department of the Army permit is not required. The Texas

Historical Commission reviewed the project under Section 106 of the National Historic

Preservation Act of 1966 and the Antiquities Code of Texas and determined that the

project should have no effect on historic properties and that no further review would be

necessary from the Texas Historical Commission. Subsequent communications between

the Commission and Reclamation are currently being addressed. Additional commentsreceived from the U.S. Fish and Wildlife Service and the Texas Parks and Wildlife

Department have been addressed through correspondence and additional specifications

were added to the Construction Drawings.

Regardless of these jurisdictional determinations, it is the Districts goal to protect the

environment and its inhabitants. The Construction Drawings include specifications



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requiring the contractor to protect existing waterways, vegetation and wildlife from

unnecessary disruptions during construction. In addition, the District will file the

required Notice of Intent with the Texas Commission on Environmental Quality (TCEQ)

and prepare a Storm Water Pollution Prevention Plan prior to construction.

Delta Lake Irrigation District

Figure 1. Project Location Map



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2 INTRODUCTION

The purpose of the Delta Lake Irrigation Districts Water Conservation Project (the

Project) is to preserve and extend the existing water resources of the Lower Rio Grande

Valley. In general, water will be preserved by constructing improvements, which willreduce or recover losses due to seepage and evaporation and will allow for a more

efficient operation of the water delivery system as a whole. The Project is being

developed under the Lower Rio Grande Valley Water Resources Conservation and

Improvement Act of 2000 (Public Law 106-576) and was prepared in accordance with the

Guidelines For Preparing and Reviewing Proposals for Water Conservation and

Improvement Projects associated with the Act. Public Law 106-576 was passed to

encourage water supply improvement projects in select locations within the Rio Grande

basin. It provides funding for study, evaluation, design, and construction of irrigation

water system improvements. This Project Report was prepared to partially fulfill the

requirements of Contract Number G18900 between the Texas Water Development Board

and the Delta Lake Irrigation District.

The proposed Project is comprised of four separate components. The first component,

theReservoir Renovation Project, consists of building a 17,000 linear foot bypass canal

along the eastern edge of the eastern reservoir of Delta Lake. The second component, the

Seepage Recovery Pilot Project, consists of a feasibility study into the possibility of


The third component, the Telemetry and Flow Measurements Sites Project, includes the

installation of flow measurement devices at 20 water diversion points to monitordeliveries and send this information, by telemetry, to the District headquarters. The

fourth component, the Canal Rehabilitation Project, consists of preparing construction

drawings for the replacement approximately 17,800 linear feet of open channel laterals

with new gasket joint PVC or RCP pipe and the preparation of a plan to replace an

additional 13.4 miles of open channel laterals with pipe.

3 DISTRICT INFORMATION

The Project Applicant, Delta Lake Irrigation District (DLID or the District) was

established on June 22, 1914. The District is a political subdivision of the State of Texas,organized under and by virtue of Article XVI, Section 59 of the Constitution of the State

of Texas. It is operated under the statutes of Chapter 49 and 58 of the Texas Water Code.

The Delta Lake Irrigation District Board consists of the following five Directors:

Mr. Neal Galloway PresidentMr. Glen Hester Vice PresidentMr. Dale Murden Secretary



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Mr. James Carlson DirectorMr. Tom Wetegrove Director

The Districts legal address is Delta Lake Irrigation District, Route 1, Box 225, Edcouch,

Texas 78538. The general manager, Troy Allen, may be reached at (956) 262-2101.

TCEQ District information reports are included as Appendix 1 to this report.

4 DISTRICT FACILITIES AND WATER DELIVERY SYSTEM DESCRIPTION

The District provides irrigation, drainage and water supply functions to 148.95 square

miles of Hidalgo and Willacy Counties. As shown in Appendix 2, the District boundary

includes the cities of Hargill, La Sara, Monte Alto and part of the City of Raymondville.

The Rio Grande is the only water source for the District. All of the water diverted by the

District, from the Rio Grande, originates as surface water released by the International

Boundary and Water Commission from Falcon Reservoir. The District pumps water

northward through a 32-mile canal originating at the Rio Grande and terminating at thesoutheast corner of the East Reservoir of Delta Lake. The District water supply system

consists of 250 miles of lined or partially lined canals, 42 miles of unlined canal and 122

miles of unlined laterals. The District operates Delta Lake as a buffer for absorbing

changes in daily producer uses as well as equalization mitigating the four-day travel time

of water from Falcon Reservoir. As indicated in Appendix 1, Delta Lake is separated by

a roadway that divides the lake into a larger East Reservoir and a smaller West Reservoir.

The two reservoirs are connected via a culvert equipped with. with flow control gates.

Appendix 3 depicts the Districts water supply system.

5 DISTRICT WATER SUPPLY AND DEMAND ASSESSMENT

The Delta Lake Irrigation District has 182,966 acre-feet of authorized water rights and

has the largest amount of irrigated agriculture of the 28 irrigation districts in the Lower

Rio Grande Valley of Texas. The District is located within the boundaries of the Texas

Water Development Boards Rio Grande Regional Water Planning Group (Region M)

and delivers water to the North Alamo Water Supply Corporation and the cities of

Raymondville, Lyford, Hargill, La Sara, and Monte Alto. The Districts 5-year average

annual water diversion was 80,944 acre-feet for 1998 to 2002. The Districts 5-year

average annual water diversion for irrigation is 75,704 acre-feet per year and 5,240 acre-feet per year for municipal and domestic water use. The District reports an estimated

water delivery efficiency of approximately 63%.

An assessment of the current and future water supplies and demands for Hidalgo and

Willacy Counties are included in the Adopted Regional Water Plan (the Region M

Plan) published in January 2001 by the Texas Water Development Boards (TWDB) Rio



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Grande Regional Water Planning Group (Region M). According to the Region M Plan,

the population in Hidalgo County is expected to more than double in the next 50 years

from approximately 559,922 people in 2000 to 1,435,379 in 2050; while the population

within Willacy County is expected to grow over 37 percent from 21,165 to 29,077 for the

same period. With the population growth, some of the land currently used for farming

and ranching will be converted to more urban use. As such, municipal water demand is

expected to more than double in Hidalgo County over the next 50 years from 109,821 ac-

ft/yr to 226,715 ac-ft/yr, and increase over 18 percent in Willacy County from 6,395 ac-

ft/yr to 7,553 ac-ft/yr. This increase will be partially offset by an expected 29.3 percent

decrease in irrigation demand in Hidalgo County (from 849,696 ac-ft/yr to 601,000 ac-

ft/yr) over the same period.

The Rio Grande is currently the only water source for the Delta Lake Irrigation District

and is expected to remain the only source in the foreseeable future. Water in the Rio

Grande from Fort Quitman, Texas to the Gulf of Mexico is apportioned to the UnitedStates and Mexico according to the 1944 Treaty. The apportionment is administrated by

the International Boundary and Water Commission (IBWC). Two international

reservoirs, Amistad and Falcon, provide controlled storage capacity for over eight million

acre-feet of water owned by the United States and Mexico. The storage capacity of these

reservoirs is reserved for two purposes, flood control (2.25 million acre-feet) and water

supply (6.05 million acre-feet) (Region M Plan). According to the Region M Plan, it is

estimated that (by 2050) the firm yield of the Amistad-Falcon Reservoir System will

decrease by nearly 115,000 acre-feet, or by nearly 10 percent, due to silt accumulation.

The water right system for the middle (between Amistad and Falcon Reservoirs) and

lower (below Falcon Reservoir) Rio Grande provides a high degree of reliability fordomestic-municipal-industrial (DMI) water rights by continually maintaining a DMI

reserve of 225,000 acre-feet in the reservoir system. Irrigation water rights are allocated

from the residual stored water in the reservoirs and, therefore, vary from year to year.

6 DISTRICTS CONSERVATION COMMITMENT

Water conservation by the District has become increasingly important due to an enduring

drought that has affected the lower Rio Grande Valley over the past several years. The

drought and the projected decrease in irrigation water supply has required the District to

place a greater emphasis on water conservation to ensure the delivery of water to the

customers they serve. Historically, the District has aggressively sought to develop ways

to deliver the maximum amount of water possible to each turnout. The District has

implemented metering of all irrigation deliveries and has invested approximately

$400,000 per year replacing small open laterals with buried pipelines. Last year the

District installed 4,800 linear feet of 36 RCP and 10,000 linear feet of 18 PVC pipe.



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This has increased the efficiency of the District and the growers by reducing the energy

used per acre irrigated.

The proposed Water Conservation Project is proposed to continue the Districts

commitment to conserve water and energy. The components were selected as priorities

from a list of 11 major and 37 minor projects identified throughout the Districts waterdelivery system. Constructing the proposed bypass canal will reduce the seepage and

evaporation losses associated with transporting water through the East Reservoir of Delta

Lake. Recovering seepage water along the Willacy Canal will reduce the pumping costs.

The installation of the flow measurement devices will allow the District to remotely

measure the amount of water delivered from each of the 20 diversion points to the

different canal systems. By monitoring the information, the District will be able to

reduce the amount of excess water that is passed through the system. Replacing open

laterals with pipelines will reduce the evaporation and seepage losses, reduce on-farm

demand and reduce the quantity of water spilled. Reducing and/or recovering losses dueto evaporation, seepage and spills will allow more water to be available to each customer

in times of shortages.

Given that the Rio Grande is the Districts only anticipated water source, it is the

Districts goal to maximize efficiency by reducing excess pumping and seepage and

evaporation losses. Increased efficiency will postpone the need to develop new water

supplies. Since agricultural crops are a commodity, and their annual yield is dependent

on many factors (including price, weather, supply and demand), it is impossible to

determine the exact date that the development of new water supplies may become a

necessity. Regardless of the water source, the Delta Lake Irrigation District is committedto conserving both water and energy today and in the future.

7 PROPOSED PROJECT DESCRIPTION

7.1 Reservoir Renovation Project

TheReservoir Renovation Projectconsists of the construction of a bypass canal along the

eastern edge of the East Reservoir of Delta Lake. This bypass canal will begin at the

southeastern corner of the reservoir, where the Main Canal supplies the lake, and

terminate at a pump house along the reservoirs north edge. A project location mapshowing the bypass canal location is included as Appendix 4.

This project is crucial to supply irrigation and domestic water to the northern and eastern

portions of the District including the cities of Raymondville and Lyford during periods of

drought. With the current system, raw water is transported to these areas via the Delta

Lake. It has been estimated that in a dry summer month, that over 1,700 acre-feet of



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water would need to be placed in the East Reservoir to deliver about 400 acre-feet at the

northeast corner to overcome losses due to evaporation. This represents a loss rate of

approximately 77 percent. If current drought conditions continue and expected future

decreases in water supplies occur, the delivery of raw water through Delta Lake will not

be possible.

In 1998 and again in 2002, the Rio Grande Valley was under extreme drought conditions.

As such, the Delta Lake Irrigation District came very close to depleting its allocation of

irrigation water and thus the transport water that is necessary to convey the municipal

water through the East Reservoir of Delta Lake. North Alamo Water Supply Corporation

(NAWSC) supplies the municipal water to the majority of the rural residents in Willacy

County and applied to the Texas Water Development Board for emergency grant funds to

construct the by pass canal described above. A combination rain and increased water

allocations in late summer of 2002 averted the short-term water shortage, but not the risk

that the shortage will occur again. Grant money was approved in early 2003 for theproject submitted by NAWSC. NAWSC is responsible for any technical or

administrative activities under the funding authorized by TWDB Resolution 03-9 and no

funds for such activities are being provided to Delta Lake Irrigation District or their

consultants for such activities. Copies of all technical information developed in

conjunction with the Districts TWDB-SECO project will be provided to North Alamo

WSC. The District and North Alamo will have periodic meetings to coordinate the

project and make sure that no duplication of effort is occurring.

Four potential project alternatives were identified and analyzed; construction of a new

canal and associated improvements, construction of a 24-inch transmission main,construction of a 36-inch transmission main and the no-build alternative. Preliminary

cost estimates for the 24 and 36-inch transmission mains were estimated to be from 2.2 to

4.6 times the estimated cost of the new canal. Both pipeline alternatives would require

significant clearing along the same general alignment proposed for the canal. Although

these widths are roughly half of that required for channel construction, a clear-cut swath

would still be required through the project alignment. Additionally, the transmission

capacity of the pipelines is extremely limited (12 to 27 percent) relative to the canal

alternative. No overwhelming benefits were identified that justified the additional cost

and limited capacity of the transmission main alternatives. Construction of either

transmission main was therefore eliminated as a viable alternative.

Numerous potential negative impacts are associated with the no-build alternative.

Severe curtailment of water use would be required resulting in damage to small-scale

agriculture, lawns, trees, landscaping, etc. The Development of emergency interim water

supplies would be necessary resulting in increased cost, fuel usage, air pollution and

traffic. There would also be a higher potential for public health and safety problems



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typically associated with inadequate water supplies including loss of system pressure,

system contamination, longer distribution system residence times, etc. As a result of the

significant potential negative impacts, the no-build alternative was eliminated from

consideration. Construction of a bypass canal and associated improvements was

therefore selected as the recommended alternative.

The proposed bypass canal will be constructed along the inner edge of the eastern

embankment, utilizing the existing berm. The western embankment will be constructed

from material dredged from the bottom of the reservoir. The trapezoidal cross section

has a ten-foot bottom width, 2:1 side slopes and has been designed to carry a minimum

flow of 160 cfs. The bypass canal will not be lined in conjunction with this project.

Control structures have been designed to accommodate the six existing diversion points

along the eastern edge of the reservoir. Radial gates will be installed at the Main and J

Canals to provide better flow control. The radial gates at the Main Canal will allow the

East Reservoir of Delta Lake to continue to be utilized as a reservoir for the District, but

in an off-line instead of in-line capacity. The proposed control structures will allow

the steady flow of water to the bypass canal and excess water will be diverted into the

East Reservoir. In times of extreme water shortages, this system will allow the District to

still provide raw water when lake levels are low. The radial gates at the J canal will

allow the flow to be measured and provide a drain for the East Reservoir. The existing

control structures at the No. 1, No. 2 and No. 3 Canals will be replaced with concrete

vaults containing weirs to allow the District to control and measure the flow into each of

the laterals. Concrete wells will be constructed at Relift pumps houses No. 9 and No.

47. Concrete flumes will be constructed along the bypass canal upstream of each of thecontrol structures and flow measurement devices will be installed at each of the diversion

points. These flow measurement devices will be connected to the proposed telemetry

system.

7.2 Seepage Recovery Pilot Project

The Seepage Recovery Pilot Projectconsists of a feasibility study into the possibility of


Because of the size of the canal, concrete or urethane lining were rejected as possible

alternatives because they were estimated to be prohibitively costly. The seepagerecovery project was selected as the recommended alternative. It was estimated that the

energy required to pump the recovered seepage back into the Main Canal will be

approximately 25% of the energy required to pump water from the Rio Grande, or for

every acre-foot of seepage water that is salvaged, the District will reduce energy cost per

acre-foot by 75%. A Project Location Map showing the study area is included as

Appendix 5.



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A feasibility study was performed to determine the most economical region of the project

study area to recover seepage water. A copy of the feasibility study is included as

Appendix 8. The project study area was defined as the entire length of the Willacy Canal

from the Rio Grande to Delta Lake. The Soil Survey of Hidalgo County, Texas, the Soil

Survey of Willacy County, Texas and the Soil Survey of Cameron County, Texas,

published by the United States Department of Agriculture, Soil Conservation Service in

cooperation with the Texas Agricultural Experiment Station, were consulted to determine

the general soil characteristics of the study area. According to the Surveys, soils along

the Willacy Canal range from clay, with a low permeability rate of less than 0.06 in/hr, to

fine sandy loam, with a permeability rate between 0.6 to 6.0 in/hr. The approximately

three-mile length of canal from the North Floodway southward to railroad crossing was

selected for the feasibility study area, due to its soil characteristics and its identification

by District personnel as a high seepage area.

Once the feasibility study area was identified, a geotechnical engineering firm was hiredto perform borings at regular intervals along the embankment and adjacent roadway to

determine the actual permeability rate, the depth of the water table and the quality of the

water in the canal and the borrow ditch. This information was utilized to design the

subsurface telescoping toe drain system and the 5 cfs pump station to pump the recovered

water back into the Willacy Canal.

7.3 Telemetry and Flow Measurement Project

The Telemetry and Flow Measurement Project includes the installation of flow

measurement devices at 20 diversion points within the Districts water supply system.These devices will be permanently installed to monitor deliveries into particular laterals

of the system and send this information, by telemetry, to the District headquarters. This

information will allow the District to track water usage, identify where losses are

occurring and allow the District to forecast and provide for future water uses. By having

more information, the District can operate the system more efficiently. A project location

map showing the flow measurement sites is included as Appendix 6.

The 20 diversion points were designed with one or multiple measurement devices

depending on the diversion structures located on the site. Each of the measurement

devices on the individual sites will be connected to a single telemetry system. Thediversion structures can be broken into two categories, pump houses (closed conduit

flow) and check structures (open channel flow).

At all of the pump house sites, water is drawn from the supply canal with single or

multiple pumps and discharged to a pump well. Once the water enters the pump well it is

distributed to single or multiple distribution lines for delivery to the customer(s). Each



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pump well is constructed with a wall that acts an overflow weir. If the pump produces

more water than the customer uses, the water fills up the well, eventually spills over the

weir and flows through a recycle line that returns excess water back into the supply canal.

When small flows are required, a valve at the bottom of the weir wall can be opened to

allow water to flow directly from the supply canal to the distribution line without the use

of the pump. With the present system, the District has no mechanism to routinely

quantify the amount of water a pump house is producing in relation to the amount

actually delivered to the customer.

The District wanted a mechanism for determining how much water each of the pump

houses were producing so they could compare this to the amount of water needed. In

addition, they wanted to be able to reduce the amount of water being recycled without

constant visual monitoring. It was decided that the flow from each pump would be

metered with either a run-time meter or a pipeline meter depending on the pump house

characteristics. Each of the pump well weir walls would be equipped with a submersiblepressure transmitter to monitor the level of the water in the well. When the water level

exceeds the height of the weir for a specified period, the pump would shut off. Once the

water level drops below the crest of the weir, and the resting period has passed, the pump

would again run.

Due to their reliability, accuracy and suitability for the sites, saddle mount propeller

meters were chosen to meter the flow in the pump discharge line. Each meter will be

protected from vandalism and theft by either a lockable concrete or welded expanded

metal enclosure. Concrete enclosures will be constructed at sites where the discharge

pipe(s) are located below grade and welded expanded metal enclosures will beconstructed at sites where the discharge pipe(s) are located above grade. Sites equipped

with a propeller meter will also be equipped with a calibration port, located upstream of

the meter, to calibrate the meter with a portable flow measurement device. At sites

without sufficient pipe length to install a propeller meter, a run-time meter will be

installed on the pump to measure the amount of time the pump is running. The pump

characteristics will be utilized to prepare a rating curve for converting the measured time

to flow.

At each of the check structures, the flow will be measured downstream from the check

structure using a flow measurement structure or device. The canals containing the checkstructures could be divided into two categories; large (top width in excess of 20-feet),

earthen canals and small, concrete-lined canals. Based on their ability to be computer

calibrated using as-built dimensions, long-throated flumes were selected for flow

measurement of the small, concrete-lined canals. A cross-section from the existing canal

was utilized to design a flume for each of the sites using the WinFlume software. Rating

tables were prepared for each of the flumes based on the proposed design. Once the



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flumes have been constructed, as-built dimensions will be tables for use in determining

flows at different elevations. Each flume will be equipped with a submersible pressure

transmitter, housed in a stilling well, for determining the water level in the approach

section of the flume and a staff gage for visual verification.

It was decided that a velocity flow meter would be the most cost effective and accuratemetering device for the large earthen canals. A Doppler meter, which measures velocity

in the channel, will be installed at each of these sites. The meter will be installed in a

concrete slab constructed along one bank of the channel. The slab will be located

sufficiently downstream from the check structure to minimize unsteady flow. The meter

will measure the velocity of the water and will be equipped with an integrated pressure

sensor for water surface level measurement. A rating curve will be developed for each of

the canal Doppler meter sites to determine the flow. The meters will be calibrated using

a portable metering device.

Three diversion points included in the project did not fall into any of the above

categories. The No.1, No. 2 and No. 3 Canals currently receive water from the East

Reservoir of Delta Lake via a pipeline through the existing embankment. Each of the

existing diversion structures will be removed and replaced with a concrete vault equipped

with a flow measurement device. A rating curve will be developed for each weir and will

be utilized, along with the water level, to provide the District with flow data. This

information will allow the District to control and measure the flow into each of the

laterals.

A telemetry system will be installed at each of the 20 diversion points for the District toperiodically, and on demand, poll for data from the field devices (remote telemetry unit

(RTU)), process the data into a central data base (base computer), send controls to field

devices and display the data in useful formats to water operation personnel. A Base

System will be located at the District Headquarters and will consist of a base computer,

which will hold the central database to store and convert all of the data from the RTUs,

and an antenna to receive from and transmit data to the remote telemetry systems. The

base computer will be equipped with software that will display current, last 24 hours and

monthly water and flow level data of any or all of the RTUs. It will also store all

engineering and conversion data necessary for converting flow.

A remote telemetry system will be installed at each of the flow measurement sites. Each

system will consist of the following:

Remote Telemetry Unit (RTU)Radio and RF ModemAC/DC Linear Power Supply



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These items will be mounted inside a steel NEMA 12 enclosure on a panel with room for

a storage battery to be placed on the bottom of the enclosure. A radio antenna will be

mounted on a 20-foot antenna mast for transmitting and receiving data from the Base

System.

At sites equipped with a pump house, the telemetry system enclosure will be mountedinside, on the specified wall, and wired to the existing power source. At sites without a

pump house, but where electricity is available, the telemetry system enclosure will be

installed in a steel vandal box and wired to the existing power source. When electricity is

not available, the telemetry system enclosure will be installed in a steel vandal box and a

solar panel will be added to the antenna mast to provide power.

Once the telemetry system enclosures are mounted, the RTU will be wired to the

metering device(s), the pressure transmitter, the existing pump panel(s), solar panel and

antenna, as specified in the construction drawings. The system will then be programmed

with the calibration coefficients for each site and District personnel will be trained in the

operation and calibration procedures for the Telemetry System.

7.4 Canal Rehabilitation Project

The Canal Rehabilitation Project is to replace approximately 16.8 miles of existing

concrete lined canal with buried pipeline. The following locations were evaluated as

canal rehabilitation sites:

A E-2 Canal (42 to E-2-M), E-2-M Canal, RLP No. 6 17,800 l.f.

B E-2-L Canal 12,250 l.f.C E-2 Canal (E-2-M to End) 5,150 l.f.D E-2-E Canal, RLP No. 45 15,950 l.f.E PE-10-7 Canal, RLP No. 7 7,300 l.f.F E-2 Canal (E Canal to RLP No. 45) 4,250 l.f.G E-2-G Canal, E-2-H Canal 13,950 l.f.H A Canal (A-20 to End) 11,900 l.f.

A project location map showing the canal repair sites is included as Appendix 7. This

component will save water by reducing seepage and evaporation losses and their

associated pumping requirements and costs. This will result in the flow rate of water

delivered to individuals to be increased or allow for a greater number of fields to besimultaneously irrigated.

Four rehabilitation options were considered for the damaged canal segments; relining

with concrete, line with an impervious liner, replace the canal with a pipeline or do

nothing. Preliminary cost estimates were prepared and revealed that replacing the

existing concrete en-masse was 100 to 200 percent more expensive than lining the canal



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with an impervious liner or replacing the canal with a pipeline. Additionally, the soils in

the area shrink and swell extensively in response to moisture changes. No benefits were

found to justify the additional cost and future problems of installing new concrete lining.

Replacing the existing canals with concrete was therefore eliminated as a viable

alternative.

According to an on-going study by Texas A&M University, concrete lined canals similar

in size and soil type can lose from 220 to 375 acre-feet/mile per year of water due to

seepage. Adding this to a loss of 2.2 acre-feet/mile per year due to evaporation converts

to a total from 749 to 1396 acre-feet of water loss per year for the proposed 3.37 miles of

canal. With the ongoing drought and the Districts commitment to water and energy

savings, the no-build alternative was eliminated from consideration.

Both lining the canal with an impervious liner and replacing the canal with a pipeline had

the positive benefit of eliminating seepage and low maintenance costs, but each had its

limits on cost-effectiveness. It was found that at higher flow rates, it was more cost-

effective to line the canal with a liner. At low flow rates, replacing the canal with a

pipeline was more cost-effective. Since both the liner and the pipeline would be installed

along the existing canal alignment, the environmental impacts of the projects would be

very similar. However, the segments selected for replacement are small laterals with low

flow rates and based on the above observations, replacing the canals with pipeline will be

the most cost-effective alternative.

A survey will be completed for each task. Data from the survey will then be utilized to

prepare a hydraulic study and prepare construction drawings and specifications. Task Awas completed in conjunction with this Project to determine appropriate cost estimates

for the subsequent tasks. A detailed hydraulic study for Task A was performed using the

EPANET software to determine the flow requirements, and thus the repair option, for

each segment of the affected canal. Once the flow requirements were determined, the

study was utilized to determine the size for each pipe segment. The Pipeline Hydraulic

Study for Task A is included as Appendix 9.

All proposed pipelines larger than 42-inches will be installed as reinforced concrete pipe

(RCP) and those equal to or smaller than 42-inches will be installed as polyvinyl chloride

(PVC) pipe. The pipeline will be installed in one of the embankments of the existingcanal, with its alignment parallel to the edge of the existing canal. A concrete inlet

structure will be constructed at the intersection of the proposed pipeline and the supply

canal. This structure will be located to ensure the inlet of the pipeline will remain

submerged and thus, ensuring the pipeline will remain pressurized. A turnout connection

box will be constructed at each point of delivery along the alignments. These boxes will

provide access points for debris removal by District personnel. The line gates at each



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turnout can be locked in place for the duration of the delivery once the flows have been

adjusted by District staff. This method allows for the use of portable flow meters rather

than having a flow meter at each point of delivery. A drain pipeline will be provided at

the end of each pipeline. Once the pipelines are in place, the existing canal will be

backfilled with material from each of the embankments to provide a uniform slope across

the District right-of-way.

8 PROJECT BUDGET

The total project budget for the Water Conservation Project is estimated to be $7.12

million. As shown in Table 1, below, the proposed budget was categorized by task and

includes the necessary mitigation costs, if any. The District has expended approximately

$22,000 of its own funds and received a grant from the Texas State Energy Conservation

Office through the Texas Water Development Board for $253,020. Construction cost for

the project (including project administration and contingencies) is estimated to be $7.12million. The first year operation and maintenance costs for both components of the

project are estimated to be $46,300.

An itemized construction cost estimate was prepared for each component of the Districts

Water Conservation Project. The estimated cost for theReservoir Renovation Projectis

$1,511,675. The cost estimate includes the construction of 17,000 l.f. of bypass canal

and associated diversion structures. The cost for theReservoir Renovation Projectwas

not included in Reclamations 50% cost share portion of the project [0.50 x ($7,120,000

$1,511,675)] because of concerns of Reclamations regarding the dewatering of the east

reservoir. The estimated cost for the Seepage Recovery Pilot Projectis $669,640. Thecost estimate includes the construction of approximately three miles of telescoping toe

drain and a 5 cfs pump station. The estimated cost for the Telemetry and Flow

Measurement Sites Project is $794,530. The cost estimate includes the construction,

installation and calibration of the flow measurement devices at each of the 20 sites; the

fabrication, installation, and programming of the base and remote telemetry systems; and

the training of District personnel. The estimated construction cost for the Canal

Rehabilitation Projectis $4,031,496. This cost includes the installation of approximately

16.8 miles of distribution pipeline, turnout pipeline and associated concrete structures.

The cost also includes the backfilling and re-grading of the existing concrete-lined canal.

Detailed construction cost estimates are provided in Section 13.1.

Itemized annual operation and maintenance (O&M) cost estimates were also prepared for

each component of the Districts Water Conservation Project. Annual O&M costs are

estimated to be $10,120 for the Reservoir Renovation Project, $650 for the Seepage

Recovery Pilot Project, $32,170 for the Telemetry and Flow Measurement Sites Project



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and$3,360 for the Canal Rehabilitation Project. Detailed O&M cost estimates are also

provided in Section 13.1

The amount and source of funds expended in the preparation of the project proposal and

in project planning were:

1. a proposal submitted to the Texas Water Development Board dated June 25,2002,

with a total cost of $22,000.

2. the Final Project Plan: Delta Lake Irrigation District, TWDB Contract G18900 (June

2003) with a final cost of approximately $35,000.

3. the Final Project Report: Delta Lake Irrigation District, TWDB Contract G18900

(August 2003) with a final cost of approximately $77,623.

The cost for preparation of project design documents, construction drawings,specifications, construction bid documents, funding contracts, and construction contracts

is approximately $140,397.

Table 1Project Budget (Excluding Any Federal Share for Reservoir Renovation Project)

Planning District State NADB Reclamation Total

Proposal to TWDB-SECO for Funds $22,000 $0 $0 $0 $22,00Final Project Plan $0 $35,000 $0 $0 $35,00Final Project Report $0 $77,623 $0 $0 $77,62

$22,000 $112,623 $0 $0 $134,62Design and Contracting Cost* $387,398 $140,397 $0 $0 $527,79

Total Planning and Design $409,398 $253,020 $0 $0 $662,41Construction Cost** $93,419 $0 $3,560,000 $2,804,163 $6,457,58

$502,817 $253,020 $3,560,000 $2,804,163 $7,120,007% 4% 50% 39% $7,120,00

Totals

Percent

Totals

*includes design work in addition to that work performed under the Districts TWDB project

** includes construction administration and mitigation costs, if any.

9 DETERMINATION OF WATER AND ENERGY CONSERVED

In conjunction with the preparation of the Project Report, estimates of the quantity ofwater and energy saved for each component were prepared. Existing studies of seepage,

evaporation and evapotranspiration were reviewed for their relevancy to this Project and

additional studies were performed to supplement the information.

Energy savings were calculated from the water savings for the reduced pumping costs

associated with each component. The assumed pumping system efficiency of 70% was



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based on a pump efficiency of 74%2and electric motor efficiency of 95%3. An overall

pumping system efficiency of 70% is assumed as to be a reasonable average efficiency

for pumping plants of similar design and repair to that of the Districts main pumping

plant.


Water savings for theReservoir Renovation Projectare based on the amount of seepage

and evaporation saved by transporting municipal and irrigation water through the bypass

canal instead of through the East Reservoir of Delta Lake. Since Delta Lake will still be

utilized as an off-line reservoir when excess water is available, losses due to seepage and

evaporation will be incurred most of the year. When there is a water shortage, the bypass

canal will be isolated from the system and all available municipal and irrigation water

will be transported in the bypass canal. A conservative estimate would be to assume this

event would happen during July and August of any given year. Based on this

assumption, water savings attributable to evaporation is 1,958 ac-ft and water savings

attributable to seepage is 728 ac-ft for a total water savings of 2,685 ac-ft. Table 2

summarizes the estimated water savings for the Reservoir Renovation Project. The cost

for the regulating reservoir was not included in the federal cost-share for the project

Table 2

Length of Proposed Bypass Canal 17,000 ft

Average Width of Bypass Canal 17 ftArea of Water Surface of Bypass Canal 289,000 sfArea of Water Surface of Bypass Canal 7 acNet Change of Area of Water Surface of East Reservoir 1,200 ac

Net Annual Evaporation 0.15 in/dayNet Annual Evaporation 55 in/yr Annual Rainfall 24 in/yrTotal Annual Gross Evaporation 79 in/yr July and August Net Evaporation - Total 20 inches

Total East Reservoir July and August Net Evaporation 1,969 ac-ftTotal Bypass Canal July and August Net Evaporation 11 ac-ft

Total Water Savings Due to Evaporation 1,958 ac-ft

Estimated Seepage from Lake (K = .01 fpd) July-Aug 744 ac-ftEstimated Seepage from By Pass (K= 0.04 fpd) 16 ac-ft

Total Water Savings Due to Seepage 728 ac-ft

Total Water Savings per Year 2,685 ac-ftExpected Useful Life 50 yearsElevation Change of Water Pumped 36 ft

(2003 Price Base)


2 Johnson Pump, Axial and Mixed Flow Pump Curves, 1986.3 Sanks, Robert, editor, Pumping Station Design, Reed Elsevier Group, 1998., pgs. 409.


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The Seepage Recovery Pilot Projectis estimated to recover an estimated 2,280 ac-ft/year.

This figure was calculated from the amount of water that can be pumped using the 5 cfs

seepage recovery system. It is assumed that the pump station will be operable 9 months

of the year and a 95% duty cycle for the pump. Estimated water savings for the SeepageRecovery Pilot Projectare summarized in Table 3.

Table 3

Proposed Pump Flow 5 cfsProposed Pump Flow (9 months per year) 2,400 ac-ft/yr

Total Seepage Recovered* 2,280 ac-ft/yr

Total Water Savings 2,280 ac-ft

Expected Useful Life 15 yearsNet Elevation Change of Water Pumped 16 ft

* Assumes a 95% duty cycle for pump

CALCULATION OF ANNUAL WATER SAVINGS

(2003 Price Base)


The District is authorized to divert up to 174,776 acre-feet of irrigation water and 8,200

acre-feet of municipal and domestic water for a total of 182,966 acre-feet. On average,

over the five years from 1998 though 2002, the District diverted each year from the Rio

Grande 75,704 acre-feet of irrigation water and 5,240 acre-feet of municipal water for a

total of 80,944 acre-feet. This conservative value was used in determining the quantity of

water saved by installation of flow meters throughout the Districts delivery system and

an associated telemetry system to communicate the flow information back to District

staff. This real-time flow information will allow the District to optimize the quantity of

water diverted from the Rio Grande by more accurately matching municipal and

irrigation demands and reducing the quantity of water spilled from Districts delivery

system. In future years, because of increased municipal demand and because of the

current drought, the District expects to divert more than 110,000 acre-feet per year. It is

reasonable to assume that the District will, within 5 to 10 years, divert all of its municipal

water rights (8,200 acre-feet per year) and a minimum of 75,704 acre-feet per year ofirrigation water.

The estimate of the quantity of water lost due to system spills is approximately 7.5

percent of the annual irrigation water diverted or 5,678 acre-feet per year. A conservative

estimate of the quantity of water saved by the installation of the flow meter and telemetry

system is approximately 3.5 percent of the annual irrigation water diverted or 2,650 acre-



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feet per year. As District staff increase their knowledge and skill in using the telemetry

system it is reasonable to assume that the District will reduce the quantity of water spilled

by an additional 500 to 1,000 acre-feet per year. Table 4 summarizes the estimated water

savings for the Telemetry and Flow Measurement Project.

Table 4

5-Yr Average Annual Irrigation Diversions (1998-2002) 75,704 ac-ftWater Losses Due to System Spills (7.5%) 5,678 ac-ftWater Savings (3.5%) 2,650 ac-ft

Total Water Savings per Year 2,650 ac-ftExpected Useful Life 15 yearsElevation Change of Water Pumped 36 ft


(2003 Price Base)


The replacement of 14.8 miles of open laterals with pipelines is assumed to reduce

seepage by 4,070 acre-feet per year, reduce evaporation by 59 acre-feet per year, and

reduce on-farm irrigation demand by 2,064 acre-feet per year. The 275 acre-feet per mile

reduction in seepage is based on the results from a study performed by Texas A&M

Department of Agricultural Engineering Canal Ponding Test Results, Delta Lake

Irrigation District, Edcouch, Texas published in July 2000. A copy of the report is

included in Appendix 10. Ponding tests were performed on canal reaches of similar

width, soil type and extent of deterioration. An average loss rate of 1.00 ac-ft/mile perday was determined for canal segments. Since the canal segments in our study are

assumed to be in use 9 months of the year, an average loss rate of 275 ac-ft/mile/year was

used to calculate the total water lost to seepage. The estimated total annual evaporation

rate for these canals is 3.98 ac-ft/mi/year assuming the canals are in use 9 months of the

year. Based on this rate, the total evaporation loss from February to October for the 14.8

miles of open laterals is 59 ac-ft/year. Table 5 below summarizes the values used to

estimate the water savings for the Canal Rehabilitation Project.



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Table 5

Length of Proposed Pipeline 17 mileLength of Existing Pipeline 2 mileLength of Existing Open Lateral 15 mileAverage Width of Open Lateral 8 ft

Average Water Depth 3.5 ftAverage Wetted Perimeter 13 lfArea of Water Surface 625,152 sfArea of Water Surface 14.4 ac

Net Annual Evaporation 0.15 in/dayNet Annual Evaporation 55 in/yr Annual Rainfall 24 in/yrTotal Annual Evaporation 79 in/yr

Evaporation Loss February through October* 49 in/yr Evaporation Loss February through October* 3.98 ac-ft/mi/yr

Total Evaporation Losses 59 ac-ft/yr

Estimated Seepage per Year Per Mile of Lateral* 275.0 ac-ft/yr Total Seepage Losses 4,070 ac-ft/yr

Total Off-Farm Water Savings 4,129 ac-ft/yr

Increased Application Efficiency 2,064 ac-ft/yr Total On-Farm Water Savings 2,064 ac-ft/yr

Total Water Savings 6,193 ac-ftExpected Useful Life 50 yearsElevation Change of Water Pumped 45 ft

* Assumes 9 months per year of Canal Use

Off-Farm Water Savings

On-Farm Water Savings


(2003 Price Base)

10 ECONOMIC AND CONSERVATION ANALYSIS

In June 2001, the Bureau of Reclamation published a set of guidelines for evaluating TWDB-

SECO Water Conservation Projects4. The document describes the three legislated operational

efficiency criteria for evaluating water conservation projects:

Annual acre-feet of water saved per dollar of construction costAnnual energy saved (BTUs) per dollar of construction cost, andAnnual economic savings per dollar of construction cost

4 United States Department of the Interior Bureau of Reclamation, Guidelines For Preparing andReviewing Proposals for Water Conservation and Improvement Projects Under Public Law 106-576June, 2001



26/43


Table 6 provides a summary of the economic and conservation analysis for each project

component and the project as a whole. The key Operation Efficiency criteria, from the

Guidelines are highlighted in bold for each table.

Cost estimates are in 2003 dollars. It is assumed that the initial construction cost of each

component will be expended at the beginning of the first year. Net savings in water,energy and annual O&M are assumed to accrue at the end of year 2 and continue yearly

for the expected useful life.

For the analysis we assumed: a comprehensive discount rate r=6.125% for economic

values, and a social time value rate s=4.00% for the amortization of water and energy

savings. The inflation rate for the project life is also assumed to be 2.04%. Future

savings in water and energy are discounted to the present at the social time value rate of

4.00%.5


The proposed Reservoir Renovation component will result in:

Annual water savings of 2,685 acre feet,Annual energy savings of 482,206,573 BTUs,Estimated construction cost of $1,512,525,Estimated operation and maintenance costs of $10,120,Expected useful life of the project is 50 years.


0.0888 ac-ft per dollar of estimated construction cost,15,940 BTUs per dollar of estimated construction cost, and$0.133 of economic savings per dollar of estimated construction cost.



$11.27/ac-ft$0.000063/BTU, and$7.54/$ savings

5 Texas A&M University Texas Water Resources Institute TR-203, Economic

Methodology for South Texas Irrigation Projects-RGIDECON, October, 2002



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The proposed Seepage Recovery component will result in:

Annual water savings of 2,280 acre feet,

Annual energy savings of 181,987,335 BTUs,Estimated construction cost of $573,937,Estimated operation and maintenance costs of $650,Expected useful life of the project is 15 years.


0.0596 ac-ft per dollar of estimated construction cost,4,756 BTUs per dollar of estimated construction cost, and

$0.122 of economic savings per dollar of estimated construction cost.





The proposed Telemetry and Flow Measurement component will result in:

Annual water savings of 2,650 acre feet,Annual energy savings of 475,920,826 BTUs,

Estimated construction cost of $623,980,Estimated operation and maintenance costs of $32,170,Expected useful life of the project is 15 years.


0.0637 ac-ft per dollar of estimated construction cost,11,441 BTUs per dollar of estimated construction cost, and($0.438) of economic savings per dollar of estimated construction cost.





The proposed Canal Rehabilitation component will result in:



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Annual water savings of 6,193 acre feet,Annual energy savings of 1,390,272,490 BTUs,Estimated construction cost of $4,409,558,Estimated operation and maintenance costs of ($23,520),Expected useful life of the project is 50 years.





$14.24 ac-ft$0.000063/BTU, and

$1.37/$ savings10.5 Project Aggregate

The proposed project as a whole will result in:

Annual water savings of 13,808 acre feet,Annual energy savings of 2,530,387,224 BTUs,Estimated construction cost of $7,120,000,Estimated operation and maintenance costs of $19,420,








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Axiom-Blair Engineering

Reservoir

Renovation Project

Seepage Recovery

Pilot Project

Telemetry and Flow

Mesurement Sites

Project

Economic SavingsConstruction Cost ($) $1,512,525 $573,937 $623,980Expected Useful Life (years) 50 15 15Cost of Energy ($/kW-hr) $0.10 $0.10 $0.10Energy Savings ($/yr) $14,133 $5,334 $13,948Operation & Maintenance Cost Savings ($/yr) $10,120 $650 $32,170

Dollars of Economic Savings ($/yr) $4,013 $4,684Total Dollars of Economic Savings ($) $200,633 $70,256

Dollars of Economic Savings per Dollars of Construction Cost ($/$) 0.133 0.122Dollars of Construction Cost per Dollars of Economic Savings ($/$) 7.54 8.17Discounted Present ValuesDiscount Rate 6.125% 6.125% 6.125%

Inflation Rate 2.043269% 2.043269% 2.043269%Present Value of Economic Savings ($) $82,885 $50,073

Present Value of Economic Savings per Dollar of Construction Cost ($/$) 0.055 0.087Dollars of Construction Cost per Present Value of Economic Savings ($/$) 18.25 11.46

(2003 Price Base)

SUMMARY OF ECONOMIC AND CONSERVATION ANALYSIS RESULTS

Table 6 (Sheet 2 of 2)

($18,222)($273,323)

(0.438)(2.28)

($194,802)

(0.312)(3.20)


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11 PROJECT SCHEDULE

Once the Water Conservation Project receives funding, it is estimated that the time to

completion, including bidding and construction, will be approximately 2.5 years. As the

attached Project Schedule (Section 13.2) shows, the construction contracts for eachcomponent of the project could both be in place in approximately four months. The

estimated construction time for the Telemetry and Flow Measurement Project is four

months with a two-week training session, 20 months for the Canal Rehabilitation Project,

and three months for the Seepage Recovery Pilot Project. The estimated construction

time for the Reservoir Renovation Project will be 45 days for three phases for a total time

of 4.5 months. If the project is funded by November 2003, the estimated completion date

will be March 2006.

12 REGULATORY COMPLIANCE DOCUMENTATION

An Environmental Summary Report was prepared for the Project. Preparation of the

report utilized information from a wide variety of sources including the TCEQ, the U.S.

Census Bureau, the U.S. Fish and Wildlife Service, the Texas Parks and Wildlife

Department, the Texas Historical Commission, the National Weather Service, the U.S.

Soil Conservation Service, the Texas Department of Transportation and others.

Additional information was collected through field reconnaissance and interviews with

District personnel. The report included a description of the proposed project including its

purpose and need, and funding sources. The Environmental Summary also detailed the

environmental impacts of the project based on the regulatory compliance requirements ofthe National Environmental Policy Act (NEPA), the National Historic Preservation Act

(NHPA), the Endangered Species Act (ESA), Section 404 of the Clean Water Act, and

other relevant Federal and State statutes. The database for the Native American Indian

Tribes was reviewed for possible tribal lands in the area. A copy of the Environmental

Summary Report is included as Appendix 11.

The following environmental impact categories were addressed in the Environmental

Summary Report:

Social and Economic Impacts

Soils

Vegetation Impacts

Endangered and/or Threatened Species

Disruption to Wildlife Habitat

Weather

Wetlands and Waterways

Flood Zones



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Storm Water

Effects of Earthwork on Water Bearing Bodies

Public Land

Land Use

Farmlands

Historical-Cultural Resources

Air Quality and Acoustic Impacts

Hazardous Materials

Traffic Hazards and Disruptions

Clearing, Grubbing and Spoil Disposal

Obstruction of Scenic Views

The Environmental Summary Report was submitted to the Texas Parks and Wildlife

Department, Texas Historical Commission, U.S. Army Corps of Engineers and the

United States Fish and Wildlife Service for review. Copies of the review correspondence

from each of the above agencies are included in Section 13.3.

The U.S. Army Corps of Engineers has determined that since the project sites do not

contain any areas subject to Section 10 of the Rivers and Harbors Act or Section 404 of

the Clean Water Act, a Department of the Army permit is not required. The Texas

Historical Commission reviewed the project under Section 106 of the National Historic

Preservation Act of 1966 and the Antiquities Code of Texas and determined that the

project should have no effect on historic properties. No further review would be

necessary from the Texas Historical Commission.

On October 15, 2003, staff member of Reclamations Austin, Texas office met with TheDistricts general manager and engineer and presented a letter dated September 15, 2003

signed by Pam Opiela for Lawrence Oaks of the Texas Historical Commission regarding

the Canal Renovation portion of the proposed Water Conservation Projects. The

comments made in such letter conflict or contradict previous letters from the Commission

regarding such project. It is anticipated that Reclamations concerns with the

Commissions September 15, 2003 letter will be resolved by ongoing efforts by the

District.

Regardless of these jurisdictional determinations, it is the Districts goal to protect the

environment and its inhabitants. The Construction Drawings include specifications

requiring the contractor to protect existing waterways, vegetation and wildlife from

unnecessary disruptions during construction. In addition, the District will file the

required Notice of Intent with the TCEQ and prepare a Storm Water Pollution Prevention

Plan prior to construction.



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13 SUPPLEMENTAL INFORMATION

13.1 Itemized Construction and O&M Cost

Component

Construction

Costs

Design,

Contracting, and

Administation Total Cost

Reservoir Renovation Project 1,236,675$ 275,850$ 1,512,525$

Seepage Recovery Pilot Project 469,264$ 104,673$ 573,937$

Telemetry and Flow Measurement Project 510,180$ 113,800$ 623,980$

Canal Rehabilitation Project 3,605,355$ 804,203$ 4,409,558$

Total 5,821,474$ 1,298,526$ 7,120,000$

(2003 Price Base)

Item Description Number Unit Unit Cost Total Cost

Mobilization 1 EA 5,000$ 5,000$Clearing and Grubbing 17000 LF 0.75$ 12,750$Divert Water to West Lake 40 HR 75$ 3,000$Canal Embankment (Excav/Const) 450000 CY 1.50$ 675,000$Main Canal Check Structure 1 EA 225,000$ 225,000$"J"-Canal (Raymondville) Check Structure 1 EA 125,000$ 125,000$Pump House Diversion Structure 2 EA 7,500$ 15,000$Canal Diversion Structure 3 EA 10,000$ 30,000$Grade Control Surveying 160 HR 50$ 8,000$QC for Preparation 17000 LF 0.50$ 8,500$

QC for Concrete Work 17000 LF 0.50$ 8,500$QC for Pipeline Installation 17000 LF 0.50$ 8,500$

Subtotal 1,124,250$Contingency 112,425$

Total 1,236,675$


Reservoir Renovation Project

CONSTRUCTION COST ESTIMATE

(2003 Price Base)



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Mobilization 1 EA 5,000$ 5,000$Clearing and Grubbing 15840 LF 0.40$ 6,336$Field Engineering 1 EA 2,000$ 2,000$Traffic Control 1 EA 1,500$ 1,500$Location of Existing Utilities 1 EA 2,000$ 2,000$

Dewater Trench 15840 LF -$ -$Excavation 12000 CY 2.00$ 24,000$Gravel Bedding 12000 CY 7.00$ 84,000$24" PVC 5280 LF 22$ 116,160$18" PVC 7920 LF 15$ 118,800$12" PVC 2640 LF 12$ 31,680$Pump Station 1 EA 25,000$ 25,000$Grade Control Surveying 120 HR 25$ 3,000$QC for Preparation 15840 LF 0.15$ 2,376$QC for Concrete Work 15840 LF 0.15$ 2,376$QC for Pipeline Installation 15840 LF 0.15$ 2,376$

Subtotal 426,604$Contingency 42,660$

Total 469,264$


Seepage Recovery Pilot Project

CONSTRUCTION COST ESTIMATE(2003 Price Base)



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Site Electrical Work 20 EA 1,500$ 30,000$Type I Flow Meter Enclosure 3 EA 1,500$ 4,500$

Type II Flow Meter Enclosure 4 EA 650$ 2,600$Concrete Flume 16 EA 4,000$ 64,000$Pipe Propeller Meter 7 EA 2,000$ 14,000$Run-Time Meter 4 EA 250$ 1,000$Doppler Meter 12 EA 6,500$ 78,000$

Depth Sensor 27 EA 2,000$ 54,000$Stilling Well 20 EA 1,000$ 20,000$Base Telemetry System and Software 1 LS 18,000$ 18,000$Remote Telemetry System Hardware 20 EA 2,300$ 46,000$Antenna, Mount, Cable 20 EA 250$ 5,000$Solar Panel 16 EA 100$ 1,600$

Vandal Box/Welding 14 EA 650$ 9,100$Algorithm Development 0 LS -$ -$Assembly and Testing 20 EA 1,250$ 25,000$Installation and Setup 20 EA 1,800$ 36,000$Calibration and Inspection 20 EA 1,500$ 30,000$Training and Programming 1 LS 25,000$ 25,000$

Subtotal 463,800$

Contingency 46,380$

Total 510,180$


Telemetry and Flow Measurement Sites Project

CONSTRUCTION COST ESTIMATE(2003 Price Base)



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Mobilization 1 EA 5,000$ 5,000$Clearing and Grubbing 17800 LF 0.50$ 8,900$Field Engineering 1 EA 2,000$ 2,000$Traffic Control 1 EA 1,500$ 1,500$Location of Existing Utilities 1 EA 2,000$ 2,000$

Canal Regrading 16650 LF 2.50$ 41,625$42" RCP 5000 LF 50$ 250,000$36" RCP 5000 LF 40$ 200,000$24" PVC 3900 LF 25$ 97,500$18" PVC 3900 LF 20$ 78,000$

12" PVC 500 LF 15$ 7,500$Pipeline Inlet Boxes 1 EA 2,000$ 2,000$Turnout Connection Boxes 15 EA 1,500$ 22,500$Standpipe Connection Boxes 5 EA 3,000$ 15,000$Line Gates 15 EA 750$ 11,250$Pump House Retrofit 1 LS 25,000$ 25,000$QC for Preparation 17800 LF 0.25$ 4,450$QC for Concrete Work 17800 LF 0.25$ 4,450$QC for Pipeline Installation 17800 LF 0.25$ 4,450$

Subtotal 783,125$Contingency 78,313$

Total 861,438$

PRELIMINARY CONSTRUCTION COST ESTIMATE (TASK A)(2003 Price Base)



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Canal Maintenance 3.4 MI 300$ 1,020$Vegetation Control 3.4 MI 1,000$ 3,400$Debris Removal 3.4 MI 500$ 1,700$Bypass Canal Diversion Structure 1 EA 2,000$ 2,000$"J" Canal Diversion Structure 1 EA 1,500$ 1,500$Small Diversion Structures 1 EA 500$ 500$

Total 10,120$

Pipeline Repair 3 MI 50$ 150$Pump Station Maintenance 1 EA 500$ 500$

Total 650$

Technical Staff Routine Maintenance 20 EA 800$ 16,000$Calibration/Certification/Assistance 20 EA 250$ 5,000$Software Updates 0.2 EA 2,500$ 500$Hardware Repairs

RTU/Remote Telemetry System 1 EA 1,500$ 1,500$Pressure Transmitters 2 EA 650$ 1,300$Flow Meters (parts) 23 EA 50$ 1,150$Vandalism (misc.) 4 EA 200$ 800$Solar Panels (vandals) 4 EA 500$ 2,000$Wiring 2 EA 500$ 1,000$

Staff Gages 2 EA 35$ 70$Stilling Wells 1 EA 50$ 50$

Concrete Structure Repair 1 EA 500$ 500$Miscellaneous 2 EA 1,000$ 2,000$Frequency License Maintenance 0.3 EA 1,000$ 300$

Total 32,170$

Pipeline Repair 16.8 MI 200$ 3,360$

Total 3,360$

Total Annual Operations and Maintenance Cost 46,300$

Telemetry and Flow Measurement Sites Project

Canal Rehabilitation Project


Water Conservation Improvements Project

ANNUAL OPERATIONS AND MAINTENANCE COST ESTIMATE

Reservoir Renovation Project

Seepage Recovery Pilot Project



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13.2 Construction Schedule

Axiom-Blair Engineering


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13.3 Regulatory Compliance Documentation



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Delta Lake Irrigation District PROJECT REPORTDelta Lake Irrigation District PROJECT REPORT

Axiom-Blair Engineering Page 39Axiom-Blair Engineering Page 39


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Delta Lake Irrigation District PROJECT REPORTDelta Lake Irrigation District PROJECT REPORT

Dlid Proj Rpt

Documents

Transcript of Dlid Proj Rpt