BORDER ENVIRONMENT COOPERATION COMMISSION
TOWNSHIP OF HEBER, CALIFORNIA
STEP II DOCUMENTATION
Water Treatment Plant Expansion and Improvements to the Wastewater Collection and Water Distribution Systems
TABLE OF CONTENTS
2. GENERAL PROJECT DESCRIPTION
3. HUMAN HEALTH AND ENVIRONMENT
APPENDICES
Appendix A: Construction Plans – System Improvements
Appendix B: Environmental Assessment
Appendix C: HPUD Master Plan
Appendix D: Water Treatment Permit
Appendix E: Dept. of Health Services Engineering Report
Appendix F: Demographic Information
Appendix G: Average Water & Wastewater Rates & Accounts
Appendix H: Financial Statements - Historical
Appendix I: Sphere of Influence Documentation
Appendix J: Operation & Maintenance Statements Pro Forma
Appendix K: El Centro, CA Water Rate Study
Appendix L: Calexico, CA Water Rate Study
Appendix M: Present Worth Analyses
Appendix N: Letter of Legal Authority
Appendix O: Heber Urban Area Plan
TABLES
2-1 Proposed Schedule of Compliance
2-2 Summary of Ultimate Population Projections
2-3 Summary of Ultimate Land Use, Equivalent Population, and Projected Flow
2-4 Estimated Construction Costs – Water Treatment Plant Improvements
2-5 Estimated Construction Costs – Water Distribution System Improvements
2-6 Estimated Construction Costs – Wastewater Collection System Improvements
5-1 roject Financial Structure
5-2 Probable Operation and Maintenance Costs – Water Treatment Facility
5-3 Estimated Capital Costs
FIGURES
2-1 Project Location Map
5-1 Heber Public Utility District Organization Chart
BORDER ENVIRONMENT COOPERATION COMMISSION
STEP II DOCUMENTATION
DETAILED PRESENTATION OF PROJECT FOR CERTIFICATION
Heber, California is a small, rural, unincorporated township located near the Mexican border in southern California. Its population is listed at 2,566, according to the 1990 Census. Estimates place the current population at approximately 3,426 persons. The township of Heber covers an area of approximately 800 acres, with a sphere of influence encompassing approximately 10.3 square miles. The surrounding area consists primarily of large tracts of farmland and the systems needed to maintain them.
The makeup of the township is approximately 70 percent residential homes and 30 percent commercial entities. At this time, there are no heavy industrial wastewater contributors in the system. In general, the wastewater generated by the township would be classified as residential.
The township of Heber is located approximately 117 miles east of San Diego, and 5 miles north of Mexicali, Baja California, Mexico. The location maps are shown in Figure 2-1. Heber obtains its drinking water from the Colorado River via the Imperial Valley Irrigation System.
The Heber Public Utility District is regulated by the water quality standards established by the United States Environmental Protection Agency (EPA) and by the State of California Department of Health Services, Office of Drinking Water. The water treatment system permit number is 04-14-98P-054 (Appendix D).
Formed in 1933, the Heber Public Utility District (HPUD) owns and operates the water treatment facility. Originally, the water treatment plant consisted of settling ponds followed by chlorination. In the early 1970’s a 300 gallon per minute clarifier and pressure sand filters were installed. Subsequent upgrades in the early 1980’s eliminated the 300 gpm clarifier, replacing it with an unit capable of producing water at 1,150 gallons per minute.
The current facility consists of three raw water sedimentation basins, chemical addition, upflow solids contact clarification, pressure sand filtration, post-chlorination and finished water storage.
The District receives its raw water from the Imperial Irrigation District (IID) via the Central Main Canal and then the Dogwood Canal, Delivery No. 37-A. The Dogwood Canal is periodically taken out of service by the IID for maintenance, typically for 3 days every other month. During those periods, the HPUD uses the raw water stored in the three sedimentation basins, which hold a combined 7.1 million gallons. At current usage rates, this allows sufficient water to supply the District during a 7-day outage.
Finished water storage totals 2.45 million gallons (MG), with one 1.7 million gallon tank and one 750,000 gallon tank. A 250,000 gallon tank is also at the site but is in need of extensive rehabilitation and is currently not in use.
A single pressure zone serves the finished water distribution system. A booster station equipped with variable speed, high service pumps, supplies pressure to the system. With the addition of three new pressure sand filters in 1997, the treatment facility is rated to treat 900 gallons per minute, which is approximately 1.3 million gallons per day. The HPUD is required to notify the California Department of Health Services within 24 hours if this treatment rate is exceeded. However, with downtime for filter backwash, the plant typically produces approximately 1.0 million gallons per day.
The Heber Public Utility District (HPUD) was notified by the State’s Department of Health Services (DHS) of their concerns associated with the existing system in a letter and engineering report dated December 8, 1998 (Appendix E). These concerns have caused the DHS to place a moratorium on new connections to the water system. As of this date, no more than 1,000 services are allowed for the HPUD system until the treatment plant is upgraded. The HPUD currently serves approximately 685 metered connections.
The HPUD was ordered to bring their water treatment system into compliance and to submit a compliance schedule for review. A copy of the schedule of milestone dates is included below in Table 2-1. In addition to the water treatment system, Heber has experienced problems with their water distribution and wastewater collection systems. These items will be addressed below. HPUD is seeking certification of this project from the Border Environment Cooperation Commission (BECC) in order to be eligible to obtain funding from the North America Development Bank (NADB) Border Environment Infrastructure Funds (BEIF) to enable the District to make improvements to each of these systems.
Existing Water Treatment Plant
Portions of the existing treatment plant are over 25 years old and have reached their maximum hydraulic treatment capacity, necessitating this proposed expansion. In addition to the hydraulic constraints of the units, some have reached the end of their service life and are in need of replacement due to deterioration.
The banks of two of the three basins are not lined with concrete and show substantial erosion from wind-generated wave action. The basins are not linked together to allow the operators to divert raw to or from any of the three as necessary. The raw water pumps and valves are aged and in need of replacement. The solids contact clarifier is rusting
from the inside and has been patch welded several times. Should this unit fail completely, HPUD would lose its ability to produce potable water at the plant, as no backup treatment unit is available at the plant.
The DHS has directed the HPUD to eliminate the pressure sand filters currently in use at their plant. This is primarily due to concerns over the risks associated with allowing partially filtered water to enter the distribution system immediately following the backwash phase of the filter operation. Other concerns at the plant include the lack of adequate fencing around the perimeter of the facility. The existing barbed wire fencing does not prevent animals from wandering onto the plant site and becoming trapped in the raw water basins.
Four options were examined to upgrade the water treatment/delivery system. These options are:
The fourth alternative was selected as the most appropriate.
A 10-year planning period was used as the basis of the projections contained herein.
Water Distribution System
Areas of concern also exist within the water distribution system of Heber. Some of these deficiencies are noted in the Water/Sewer Master Plan completed by Waddell Engineering in December 9, 1997, which is included in Appendix C.
As part of the Step II documentation process, Garver Engineers obtained and reviewed existing design plans and as-built drawings for the Heber water system. Those plans were then used to build an extensive Cybernet model to analyze the HPUD distribution system. Cybernet runs within AutoCad, allowing graphical representation of the model results developed, and can analyze complex distribution systems under a variety of conditions. Using the model, we are able to perform steady state and extended period use simulations.
This model computes system pressures for any demand condition. The demand alternatives used for our model were Average Day Demands, Max Day Demands and Peak Hour Demands. A fire flow scenario was also executed for each node in the model. Using max day demands, this scenario models the resultant pressures throughout the system caused by a fire flow demand at a single location. The information gained from the execution of this model was used to determine pipe sizes, pump size requirements, operation and rehabilitation requirements as well as overall master planning efforts. This was done to identify areas within the system that were deficient and that should be upgraded.
While computer modeling of the distribution system provides an excellent representation of what can be expected from an actual system, certain limitations do exist. The exact current demands can not be determined for the system. Therefore, average day demands were computed from past water usage records from the HPUD for the past 32 months.
The maximum day demand multiplier was calculated from these records. Field measurements of tank levels, pump station outputs and fire hydrant flows were taken at various points in the system. The field data was then compared with the average day Cybernet run and the model calibrated accordingly. The water demands must be estimated for future requirements and the water distributed throughout the system based on those assumptions. Also, the program can describe the response of the system for a single set of conditions.
The model conditions were programmed to reflect the "worst case" scenario, such as maximum day, peak hour, and/or maximum day plus fire flow demands. A system that is adequate under these conditions is assumed to also be adequate under normal, less demanding periods. To verify the assumptions made in preparing the computer model, we also used actual field flow test data as a basis for comparison and calibration.
The deficiencies identified within the HPUD system include:
Of primary concern to the HPUD is the deteriorating condition of several of the older distribution lines throughout their system. These lines tend to leak treated water to the ground surrounding them and can lead to catastrophic failure of the line. In addition to the loss of potable water, the potential for cross-contamination from a leaking/failed line is greatly enhanced, which in turn increases the health risk to the community.
The distribution system lacks working isolation valves on some primary junction lines throughout the District. These valves would enable the Utility to isolate a particular line for repair without having to shut down major portions of the system. One task to be completed includes directing the District’s operations personnel to identify which of the valves are operable and which need to be replaced. This valve replacement is part of the proposed improvements project.
The District has no backup emergency power generation on the main high service pumps, which forces the Utility to rely on the backup service pumps, which were part of the original distribution system. These old pumps cannot deliver the required quantities of water, at pressure, throughout the District. A diesel backup unit with automatic switchover powers them. This power generation system is capable of supplying power to the plant and the original distribution pumps but not the main high service pumps. At this time, the system averages three power outages per year.
This proposed improvements project includes the installation of an emergency backup power generation system with automatic switchover to run the main, high service pumps. Should a power outage occur during a catastrophic event, the emergency backup generator would automatically activate, powering the main finished water pumps. This would allow the Utility to continue to deliver water at the required fire flows and pressure throughout the system for an extended period of time.
In summary, the proposed project includes the replacement of 9,600 linear feet of water distribution lines, the installation of 36 new fire hydrants, 25 valves, and 110 service re-connections.
Wastewater Collection System
The wastewater collection system through many of the older parts of Heber has been in place for decades and is in need of upgrade. In addition to extensive discussions with the HPUD operations staff, Garver Engineers analyzed the entire sewer collection and distribution system using EaglePoint software. The modeling module runs within AutoCad, which allows graphic presentations of the collection system plan views, hydraulic profiles, individual sewer profiles, etc. We prepared the sewer model from record drawings of the sewers within the collection system.
The wastewater collection network was examined to identify subbasins surrounding nodes (demand points) in the HPUD water distribution system model. The average day water demand at each node was applied to the downstream reach of the sewer system within that node’s subbasin.
The assumption was made that all of the water distributed by the HPUD system is collected within the sewer system. This assumption does lend some conservatism to the modeling, since, obviously, not all of the water consumed by the District is discharged to the sewer system, e.g., water used by lawn sprinklers and in car washing.
A maximum instantaneous flow multiplier was applied to average day sanitary sewage flows to determine peak sanitary flow. The multiplier was computed by the model for each reach of sewer line, based on tributary population. The multiplier formula used is M = [18+(P)0.5/4+(P)0.5], where P is the population in 1,000’s.
The computer model calculates the population equivalent by determining the average daily flow in each reach (sum of total line flow tributary to the sewer in question) and dividing that total average daily flow by 100 gallons per capita per day.
Pump station discharges to downstream reaches of the gravity sewers were adjusted to match the computer predicted pump station maximum instantaneous inflow or to match the maximum rated pump capacity of the existing pumps, whichever is greater.
The deficiencies identified as a result of this analysis are:
In summary, the proposed improvements entail the replacement of 6,070 linear feet of sewer lines with PVC pipe, 10 manholes, 60 manhole connections, the replacement of one of the two pump stations, and the rehabilitation of the second pump station.
The following table summarizes the estimated capital costs of the proposed projects.
|
Estimated Capital Cost |
||||
|
ITEM |
USD |
|||
|
Water Treatment Plant Expansion |
$2,620,400 |
|||
|
Improvements to the Water System |
$764,700 |
|||
|
Improvements to the Wastewater System |
$957,300 |
|||
|
TOTAL |
$4,324,400 |
|||
In addition to capital costs, the water treatment plant will have an annual operation and maintenance (O&M) cost of $149,300. The O&M cost of the water distribution and wastewater collection systems will remain practically the same as it is today, or could potentially decrease as the repair requirements will be reduced by the improvements.
The North American Development Bank (NADB) developed a financial evaluation to determine the amount of grants and loans the District would be eligible to obtain from this institution. These amounts, in addition to other sources of funding, are described in the following table.
Project Financial Structure
|
Available Funding |
Amount ($) |
% of Total |
|
Loans |
|
|
|
USDA loan |
1,126,500 |
25.94 |
|
Loans Subtotal |
1,126,500 |
25.94 |
|
Grants |
|
|
|
USDA grant |
1,223,500 |
28.18 |
|
BEIF grant |
1,992,400 |
45.88 |
|
Grant Subtotal |
3,215,900 |
74.06 |
|
TOTAL |
$4,324,400 |
100% |
In addition to BEIF construction assistance, NADB analyzed the possibility of providing BEIF transition assistance to allow for a gradual increase in rates, as described in the following section. A total of $152,000 is recommended as transition funds.
Furthermore, the NADB analysis identified the modifications in the rate structure that would be necessary to ensure the financial feasibility of the project. The current water rate for residential users of $21.75 per month includes a 20,000 gallon water allotment. The proposed rate structure is to set a base fee starting at $20 per month with no water allotment. The water usage fee would immediately increase from 35 cents per 1,000 gallons to 36 cents per 1,000 gallons and all water consumed will now be charged. The base fee will then increase $1 per year for the next seven years until it reaches $26 by fiscal year 2005-2006.
Similarly, the current monthly wastewater fee rate of $22 per month will increase by $1 per year for the next seven years, bringing the rate to $29 by FY 2005-2006. This proposed wastewater rate structure includes the rate increase proposed for the upgrade and expansion of the wastewater treatment plant project previously certified by BECC.
As required by the BECC, the project sponsor implemented the public participation process. The process included the development of a public participation plan, the formation of a steering committee composed of respected members of the community, and the distribution of project information door-to-door. The project sponsor held two public meetings, which took place on July 22 and August 5, 1999. The results of the financial evaluation were presented during the second public meeting.
The project is consistent with BECC’s definition of sustainable development: "…conservation oriented social and economic development that emphasizes the protection and sustainable use of resources, while addressing both current and future needs, and present and future impacts of human actions."
All environmental parameters have been met and the increase in water demand and use is consistent with local planning documents. The expansion of the water treatment plant coupled with the upgrade of the water distribution and wastewater collection systems will require little in the way of increased institutional capacity, as the proposed treatment technology is very similar to that already in use at Heber. As a complement to this project, the BECC and NADB are providing technical assistance funds to enhance the institutional capacity of the Heber Public Utility District.
The projects comply with all environmental regulations and are consistent with general plan designations and/or zoning.
SECTION 2 - GENERAL PROJECT DESCRIPTION
PROJECT TYPE
Public Sector - Water Treatment Plant Expansion, Water Distribution and Wastewater Collection Systems Improvements
This project consists of the expansion of an existing raw water treatment plant, improvements to the water distribution system and the sewer collection and pumping system. Each of these is a BECC priority area.
PROJECT TITLE
Heber Public Utility District
Water Treatment Plant Expansion and Improvements to the Wastewater Collection and Water Distribution Systems
PROJECT DESCRIPTION
The Heber Public Utility District is proposing improvements to the District’s Water Treatment Plant as well as to the water distribution and wastewater collection systems. These improvements are aimed at addressing deficiencies noted by the regulatory agencies that permit this Utility District. The proposed expansion project is designed to accommodate the needs of the HPUD through the year 2010.
PRIMARY APPLICANT INFORMATION
Heber, CA 92249
PROJECT LOCATION
Project Location: California, U.S.A
Site Location: Rural Area
Description of Project Location
The project is located in the township of Heber, California, which is located on Highway 86, approximately 5 miles north of the United States/Mexican border, in southern California. The treatment plant is located on an 2.7-acre site on Ingram Avenue, in Section 28, T16S, R14E of the Heber Quadrangle. Location maps are shown by Figure 2-1.
FIGURE 2-1

PROJECT LOCATION MAP

The topography of the land is extremely flat, sloping approximately five feet per mile to the northwest. The elevation of the surrounding area is at or below sea level. Rainfall totals approximately 3 inches per year. Temperatures vary from the nineties to low one hundreds in the summer (with some days exceeding 120 degrees) to the low 40s in the winter.
The area of impact of this treatment plant expansion is the township of Heber. The surrounding sphere of influence will not be significantly impacted due to the few collection and distribution lines in the area. Although a likely future occurrence, as Heber expands into the sphere of influence, the surrounding area will require additional water produced by the treatment plant, which are included in the overall design by virtue of the population projections used in the plant’s design criteria.
PROJECT DESCRIPTION AND WORK TASKS
Project Description
The primary human health and environmental issues to be resolved are the overloaded and deteriorating water treatment facility, inadequate water distribution lines and undersized wastewater collection infrastructure.
The ability of the water treatment system to produce sufficient quantities of high-quality finished water is continuing to diminish as the system ages. The State’s Department of Health Services (DHS) has placed a moratorium on new water service connections for the HPUD until the pressure filter system is removed from service and the plant upgraded. The problems associated with the pressure filters are primarily concerns of inadequate filtration of water immediately following the filter backwash cycle.
Also of concern is the solids contact clarifier in use at the plant. This unit is over 15 years old and is deteriorating from the inside out. Should the single clarifier require service for an extended period of time, the township of Heber could conceivably run out of potable water in as little as three days.
Additional items of study include the capacity of the water distribution system to deliver treated water to the District at the required pressure and flow rate to provide fire protection throughout the area. Undersized lines and a lack of properly spaced fire hydrants are of major concern.
With regard to the wastewater collection system, undersized gravity lines are often surcharged, causing overflow conditions in collector manholes and in nearby house service lines. In addition, the sewer lift station near 10th Street and Parkyns is in need of replacement, while the pumps in the lift station near 6th and Heber Road need to be modified to increase its discharge flow rate.
In summary, the proposed improvements include the expansion of the existing water treatment plant by means of a packaged plant. The proposed expansion will bring capacity from 1.3 million gallons per day (mgd) to 2.0 mgd, with provisions for a future expansion to 4.0 mgd. The plant improvements includes the rehabilitation of the berm and bottom of the raw water storage lagoons, replacement of the raw water pumps, removal of the existing water treatment equipment, removal of an abandoned storage tank, construction of an office/laboratory building, a new backup power generation system, and a new package water treatment plant. The package plant will be based on a clarifier/filter, consisting of two units in parallel. Each unit is composed of a solids contact section followed by clarification and rapid-sand filtration. The treated water will then be chlorinated and pumped into the finished water storage tanks.
The improvements to the water distribution system entail the replacement of 9,600 linear feet of water distribution lines, the installation of 36 new fire hydrants, 25 valves, and110 service re-connections. On the other hand, improvements to the wastewater collection system include the replacement of 6,070 linear feet of sewer lines with PVC pipe, 10 manholes, 60 manhole connections, the replacement of one of the two pump stations, and the rehabilitation of the second pump station. As part of this improvement effort, a proposed time schedule is presented in Table 2-1 below. This timeline is subject to revision by the regulatory agencies involved, but establishes a framework for the completion of these improvements.
TABLE 2-1
PROPOSED SCHEDULE OF COMPLIANCE
|
TASK |
BEGIN |
COMPLETION |
|
Begin Final Engineering Design for construction of treatment plant and improvements to the water and wastewater collection systems |
November 1, 1999 |
May 1, 2000 |
|
Bidding |
June 1, 2000 |
July 15, 2000 |
|
Construction Period |
August 15, 2000 |
May 31, 2001 |
|
Permit Compliance |
June 1, 2001 |
December 1, 2001 |
DESCRIPTION OF THE COMMUNITY
Demographic Information
The population of Heber is currently estimated at 3,426 persons. Heber lies within the Imperial Valley, at its southern end. The Community Economic Profile and the 1990 Census data are included in Appendix F. As noted, Heber is located within Census Tract 113, which is rural and primarily agricultural. The township of Heber itself covers approximately 800 acres, which is the service area of the existing system. Based on the 1990 Census, Tract 113 had a population of 5,359 persons and the Heber townsite had a population of 2,566. This represents 47.9% of the total population of Tract 113.
Given that the 1990 Census is the most recent available, population projections were based on the Southern California Association of Governments (SCAG) figures, which have been projected for Tract 113 through the year 2020. A similar growth rate was assumed for the Heber Township and it is this basis on which the future population figures are calculated. The growth rate for Heber between 1980 and 1990 averaged 1.4% annually. If this same rate were applied to Heber’s population through 1998, the current population would be estimated at 2,868 persons.
If the 1990 Census Tract 113’s population of 5,359 persons is used along with the SCAG projected population for the area (7,604 persons), the growth rate between 1990 and 2000 averages 3.56% per year. At a starting population for Heber of 2,566 in 1990, the current
population would be 3,394 persons. However, the population projection from the SCAG figure of 3,426 persons will be used throughout this report. A detail of these projections follows in Table 2-2.
TABLE 2-2
SUMMARY OF ULTIMATE POPULATION PROJECTIONS
TOWNSITE OF HEBER
BASED ON SOUTHERN CALIFORNIA AREA GOVERNMENTS (SCAG) DATA
FOR CENSUS TRACT 113
|
YEAR |
CT 113 SCAG PROJECTIONS |
HEBER |
HEBER POPULATION PROJECTION |
|||||
|
HEBER % OF CT 113 |
PRORATED/ PROJECTED @ 47.88% OF CT 113 (1) |
|||||||
|
POPULATION |
HOUSEHOLDS |
PERSONS PER HOUSE |
1990 CENSUS POPULATION |
# SEWER CONNECTS |
||||
|
|
|
|
|
|
|
|
|
|
|
1990 |
5359 |
NA |
NA |
2566 |
NA |
47.88% |
2,566 |
|
|
1994 |
NA |
1330 |
NA |
NA |
650 |
NA |
2,996 |
|
|
1997 |
NA |
NA |
NA |
NA |
NA |
NA |
3,318 |
|
|
1998 |
NA |
NA |
NA |
NA |
680 |
NA |
3,426 |
|
|
2000 |
7604 |
1769 |
4.3 |
NA |
NA |
NA |
3,641 |
|
|
2010 |
13395 |
3016 |
4.4 |
NA |
NA |
NA |
6,414 |
|
|
2020 |
20647 |
4729 |
4.4 |
NA |
NA |
NA |
9,886 |
|
** Data taken from Dudek & Associates’ WWTP Facility Plan – April 15, 1998
A demographic analysis was also included in the HPUD Master Plan (1997). This Master Plan examined the 800-acre service area for single and multi-family residential development and for commercial, institutional and industrial development, with estimated infiltration/inflow (I/I) flows included. This information is presented below in Table 2-3.
TABLE 2-3
SUMMARY OF ULTIMATE LAND USE, EQUIVALENT POPULATION, AND
PROJECTED FLOW
TOWNSHIP OF HEBER. CALIFORNIA
BASED ON ACREAGE AND DENSITY ESTIMATES FROM
HEBER PUBLIC UTILITY DISTRICT WATER/SEWAGE MASTER PLAN
(December 8, 1997)
|
Land Use |
% of Urban Area |
Acres |
Projected Density Pers./Ac |
Assumed Ultimate Percent Developed |
Ultimate Number Persons (1) |
Average Flow (gpcd) (2) |
Avg. Flow gpd |
Peak Factor |
Pk. Hour Dry Weather Flow |
|
|
|
|
|
|
|
|
|
|
|
|
Single Family Residential |
65.00% |
520 |
16 |
67.00% |
5,574 |
120 |
668,928 |
See Total Below |
|
|
Multi Family Residential |
5.00% |
40 |
64 |
67.00% |
1,715 |
120 |
205,824 |
See Total Below |
|
|
Subtotals: |
|
560 |
|
|
7,290 (1) |
|
874,752 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Commercial, Institutional, Industrial |
30.00% |
240 |
40 |
67.00% |
6,432 |
40 |
257,280 |
See Total Below |
|
|
Est. 1 & 1 (25% of above contribution) |
NA |
NA |
NA |
NA |
NA |
25% |
283,008 |
See Total Below |
|
|
Subtotals: |
240 |
6,432 |
540,288 |
See Total Below |
|||||
|
|
|
|
|
|
|
|
|
|
|
|
TOTALS: |
|
800 |
|
|
|
|
1,415,040 |
1.79 |
1,760 gpm |
|
|
|
|
|
|
|
|
|
|
|
** Data taken from the Master Plan Document (Waddell Engineers) and the WWTP Facility Plan (Dudek & Associates).
Of the 800 acres within the service area, 520 acres were assumed to be developed as single-family homes with a population density of 16 persons per acre. Multi-family housing was set at 40 acres with a density of 64 persons per acre. This yields a projected ultimate population of 10,880 at full development, as compared with the SCAG 2020 projected ultimate population of 9,886 persons for Heber.
As noted, the additional equivalent population for the remaining 240 acres of institutional, industrial and commercial developments is assumed to already be included in the base population estimates.
LOCAL ENVIRONMENTAL SERVICES
Water and wastewater service availability and supply are provided for nearly 100% of the community of Heber. These services are provided 24 hours per day.
DESCRIPTION OF PROJECT ALTERNATIVES
Water Treatment Plant Improvements – Project Alternatives
Several project approaches were examined as part of this scope of work. These alternatives include:
Option 1 – "No Project" Alternative
One option would be to take no action whatsoever and to operate the treatment plant as it is currently configured. The existing plant is operating at its maximum capacity. This situation, coupled with the State’s requirement to eliminate the pressure sand filtration, is the driving force behind the plant improvement process. The State Department of Health Services, Drinking Water Division, has placed a limit on the number of services (1,000) HPUD can serve. As noted in the December 9, 1998 report from the State, this limit will remain in effect until additional treatment capacity is provided (Appendix E).
This alternative would require HPUD to continue to run their plant at its maximum capacity and would not address the deteriorating condition of several of the units within the treatment plant system. As Heber continues to grow, these conditions will simply continue to worsen to the point of creating a very real health hazard to the community. This approach will not address any of the issues associated with this project; therefore selection of the "No Project" alternative is simply not feasible.
Option 2 – Expanding the Existing Water Treatment Plant
The existing plant is hydraulically overloaded at times but still consistently produces a high quality finished water. This plant has operated well for nearly 20 years and the HPUD personnel assigned to it are familiar with its requirements. However, the filtration technology currently being used by the HPUD is not acceptable to the State DHS. Therefore, the installation of additional pressure sand filters is not an option at this facility. Furthermore, the existing solids contact clarifier is deteriorating and is due for replacement. Therefore, this option is not considered to be a viable alternative.
Option 3 – Purchasing finished water from El Centro or Calexico
As part of the master planning process, Garver Engineers examined the possibility of abandoning the existing treatment facility and purchasing water from either El Centro or Calexico. As part of that effort, the costs associated with construction of a connecting pipeline and booster pump station were calculated. The pipeline from El Centro to Heber would be approximately 4 miles long, while a line from Calexico to Heber would be approximately 3.5 miles in length.
The estimated costs for each option are included in Appendix M. These costs were compared, on a present worth basis, with the cost of constructing a new treatment facility at the existing plant site in Heber.
Each cost comparison assumed the following:
As noted, the results of the present worth analyses are as follows:
The complete tables showing the present worth analyses and the criteria used can be found in Appendix M. In addition to the assumptions made previously, it is also assumed that a contract agreement between the HPUD and either El Centro or Calexico could be reached in a timely manner. This agreement would require extensive negotiations between both parties to reach a consensus regarding the cost of finished water, the allocation of plant capacity to Heber, the method by which future expansions are funded, and the priority given to the different large use customers connected to the system. Each of these alternatives assumes El Centro or Calexico would be willing to provide water to Heber at a reasonable price and that they have the capacity to do so.
Given the condition of the existing plant at Heber and the long lead time required for this type of negotiation, the possibility exists that an agreement cannot be reached by the time HPUD’s existing facility experiences failure of the treatment unit.
One concern is that should negotiations between the governing bodies of the entities involved begin in earnest and not result in an agreement for the purchase of water by HPUD, the District would then be forced to then pursue the construction of their own treatment system. The HPUD would then be "behind the curve" in the design and construction of their plant, which will further increase the chances the existing plant would fail before a new facility can be completed and brought online.
Given the higher present worth costs of purchasing finished water from either El Centro or Calexico and the uncertainty of successful purchase contracts being developed, this option was not considered to be the most viable.
Option 4 – Installation of a new treatment facility at the existing plant site
As noted by both the HPUD Master Plan (Appendix C) and the Department of Health Services’ Engineering Report (Appendix E), the existing plant is at its maximum capacity and cannot produce additional amounts of potable water. Additional problems center on a filtration system that is not acceptable to the DHS and a main clarification unit that is deteriorating.
One alternative to improve the existing treatment capabilities of the HPUD is to construct a new water treatment facility on the existing plant site, using technology that is similar to that already in use and that is acceptable to the State Health Department. The proposed plant would consist of packaged treatment units that are relatively simple to install and that meet the State’s requirements for type and effectiveness of a treatment system.
The proposed treatment technology is similar to that already in use, is well developed and well suited for Heber. As noted previously, the present worth cost of this option is lower than that of the purchased water alternatives and allows Heber to maintain control of their water production system (Appendix M). This option, therefore, is the preferred alternative.
Water Treatment Plant Upgrade – Project Justification
As noted above, the existing water treatment plant is currently deficient in terms of hydraulic capacity and filtration method. At the direction of the State Health Department, the HPUD has been ordered to upgrade their treatment plant to bring it into compliance. The treatment equipment is aged and deteriorating to the point of imminent failure. Continued operation using existing equipment poses a health risk to the human health and well being of the township’s inhabitants.
The basis for determining the water usage expected through the life of this study period was developed by Garver Engineers from HPUD’s current use records. This data was then correlated with the existing population data and extrapolated through the life of the project. These future flow requirements were then used to size the water treatment plant equipment. The future water requirements calculated for this project closely mirror the Master Plan completed in December 1998 for the HPUD by Waddell Engineering.
The construction of a new water treatment plant, as described above, is the best solution to this problem, as it is the most cost-effective option and eliminates the problems that must be addressed, as indicated by the regulatory agencies. In addition to new treatment units, other improvements are anticipated for the District’s plant, including lining the bottoms of all three raw water basins with concrete to facilitate regular cleaning and installing a perimeter security fence to keep stray animals from entering the plant site. Often, animals will fall into the raw water basins and drown. This occurrence, while not representing an imminent health hazard to the public, should be avoided as a standard of good practice.
Water Distribution System Improvements – Project Alternatives
The alternatives associated with this phase of the project include:
Option 1 - "No Project" Alternative
One option would be to take no action whatsoever with regard to the water distribution system. The primary reason for upgrading the size of the distribution system lines is to replace the aging, deteriorated lines located throughout the system with properly sized pipes and working valves. The human health risks associated with cross-connection contamination resulting from failing water lines are of major concern. Improvements to the distribution system will reduce the loss of potable water through leaks and would help to ensure that an adequate supply of safe, non-contaminated water is available to the residents within the community.
Improvements to the distribution system would also enable the high service finished water pumps to deliver water flows to the system that are adequate for fire protection. In addition to undersized, deteriorated water lines, there are an inadequate number of fire hydrants within the system grid to yield adequate coverage. As taking no action would not address any of the issues associated with this phase of the project, selection of the "No Project" alternative is simply not feasible.
Option 2 - Installing properly sized lines and appurtenances
This alternative involves installing properly sized water distribution lines and looping lines as required throughout the system. This upgrade in delivery capacity will allow the existing high service pumps to deliver sufficient water throughout the HPUD system. In conjunction with this upsize in delivery lines, additional fire hydrants will be installed so that adequate coverage is attained throughout the township. In most cases, hydrants will be installed where none previously existed. In other instances, new hydrants will replace undersized, inoperative hydrants that cannot deliver adequate fire flow of 1,250 gallons per minute.
The benefits gained from properly sized water lines and properly space fire hydrants are substantial, both in terms of human safety and property protection. The disadvantages associated with this type of upgrade are practically non-existent. Thus, this alternative is the preferred option chosen.
Water Distribution System Upgrade – Project Justification
Upgrade of the water distribution system will allow the township of Heber to deliver sufficient water throughout the District. Portions of the existing system are deteriorated and losses due to leakage are a consideration. Leaking, deteriorating distribution pipes present a possible venue for cross-connection and contamination of the potable water system. This health hazard can be significantly reduced if the water lines are upgraded.
Several of the water distribution lines within the older portions of the Heber system are made of cast iron. These lines have been in service for forty to fifty years and are in poor condition. The accumulation of scale on the pipe interior, coupled with general deterioration from years of service, necessitate the replacement of these piping sections.
The existing piping layout includes several dead ends, which limits the delivery capability of the system. These pipes will be looped to improve the water pressure and delivery within the distribution piping.
The installation of buried service valves on key junction lines throughout the system will allow the HPUD to isolate a particular water line for repair or replacement. This flexibility is especially important should an emergency line break occur, a result of either aged lines or an unintentional excavation. The broken line can be repaired more quickly with less water loss, a reduced chance of cross-connection contamination (and the health risks associated therein) and less loss of service to nearby connections.
The addition of an automatic switchover/emergency backup generator driving the main high service pumps will allow the HPUD to continue to deliver water throughout the distribution system at the flow and pressures required for fire protection. This will help Heber to maintain water service should a catastrophic event, such as a severe earthquake, disrupt electrical service for an extended period of time.
Wastewater Collection System Improvements
Project Alternatives
The alternatives associated with this phase of the project include:
Option 1 – "No Project" Alternative
Portions of the existing sanitary sewer lines in Heber are old and in need of rehabilitation. Primary problems include undersized and/or broken lines and inadequately sized pump stations. The undersized lines are often surcharged due to lack of capacity. This causes raw sewage flows to back up within the system. This condition often results in discharges of raw sewage onto the ground around the upstream manholes and into adjacent residences. This creates a serious health hazard and can damage property.
This option would involve taking no action at all, thus allowing the sewer surcharge/overflow conditions to continue unabated. Continued exposure of the citizens to this condition was deemed to be unacceptable. Therefore, this "no action" alternative was rejected.
Option 2 – Install properly sized sewer collection and distribution lines and upgrading existing pumping stations as required.
As part of the scope of work, Garver Engineers conducted an extensive modeling program of the existing sewer system using EaglePoint software. By integrating water usage data in a particular area, the sewer flow rates can be calculated. The sewer model is then constructed and run to highlight deficient sections of the sewer collection system. Upgrading these deficient sewer lines will alleviate the surcharge conditions often encountered by the residents in these areas.
The other key component of this system is the pumping stations located throughout the District. Of the stations operated by the HPUD, only two require any upgrade at this time. One station will be replaced entirely, as it has deteriorated and is no longer reliable, failing at times and allowing raw sewage to back up into nearby residences. The other station is in good condition but the pumps in use are undersized for the current flow conditions. This results in line surcharges upstream of the station.
The implementation of this option would be relatively simple to accomplish and would alleviate the existing surcharge conditions of the wastewater collection system. Therefore, it is recommended that this option be pursued.
Wastewater Collection System Upgrade – Project Justification
The existing wastewater collection system in Heber has problems with sewer line surcharges and subsequently, sewage overflows. This often leads to exposing the nearby residents to raw sewage. The line replacement program proposed above should increase the flow capacity of the gravity collector lines and the pump station improvements anticipated will move this wastewater onto the treatment plant more efficiently. This combination should eliminate the incidences of sewer line surcharges currently taking place within the system.
The pump station upgrade at 10th and Parkyns will eliminate the last dry pit pump station in service at Heber, replacing it with an aboveground, suction lift pump station. The pump station upgrade at involves the replacement of sheaves, pulleys and motors on the existing pumps. This modification will increase the capacity of the existing pump station so that it will have sufficient pumping capacity to handle the incoming sanitary sewage waste flows.
TABLE 2-4
ENGINEER’S OPINION OF PROBABLE CONSTRUCTION COSTS
HEBER PUBLIC UTILITY DEPARTMENT
WATER TREATMENT PLANT IMPROVEMENTS
|
ITEM
|
QTY |
UNIT |
PROBABLE UNIT INSTALLED COST |
TOTAL
|
|
RAW WATER PUMPS |
2 |
EA |
$16,800 |
$33,600 |
|
VALVES AND PIPING |
1 |
LS |
$5,600 |
$5,600 |
|
2 MGD TREATMENT UNIT |
1 |
EA |
$675,000 |
$675,000 |
|
FINISHED WATER PUMPS |
2 |
EA |
$16,800 |
$33,600 |
|
FINISHED WATER PUMP STATION WET WELL |
1 |
LS |
$4,200 |
$4,200 |
|
VALVES AND PIPING |
1 |
LS |
$5,600 |
$5,600 |
|
BACKUP GENERATOR SET |
1 |
LS |
$60,000 |
$60,000 |
|
NEW LAB BLDG. |
2500 |
SF |
$70 |
$175,000 |
|
DEMOLISH ABANDONED 250,000 GAL STORAGE TANK |
1 |
LS |
$15,000 |
$15,000 |
|
DEMOLISH OLD TREATMENT PLANT EQUIPMENT |
1 |
LS |
$25,000 |
$25,000 |
|
PERIMETER 6’ SECURITY FENCE |
2900 |
LF |
$11 |
$31,900 |
|
CONCRETE LINING RAW WATER BASINS |
2980 |
CY |
$200 |
$596,000 |
|
CONCRETE SEALANT |
42000 |
SF |
$1 |
$42,000 |
|
12" DIP WATER LINE |
1 |
LS |
$9,000 |
$9,000 |
|
BUILDING FOR CHLORINATION EQUIP. AND MCC |
1 |
LS |
$10,000 |
$10,000 |
|
MCC & VFD FOR PUMP STATION |
2 |
EA |
$47,400 |
$94,800 |
|
CHLORINE FEED EQUIPMENT |
1 |
LS |
$8,000 |
$8,000 |
|
BLAST AND RE-COAT EXISTING 750,000 GAL. TANK |
25000 |
SF |
$5 |
$125,000 |
|
MISCELLANEOUS CHEMICAL FEED EQUIPMENT |
1 |
LS |
$5,000 |
$5,000 |
|
SHELTER FOR TREATMENT PLANT EQUIPMENT |
1 |
LS |
$50,000 |
$50,000 |
|
ELECTRICAL CONTROLS - WATER TRMT. PLANT |
1 |
LS |
$62,000 |
$62,000 |
|
RAW WATER PIPING AND VALVES |
1 |
LS |
$30,000 |
$30,000 |
|
|
|
|
|
|
|
PROBABLE CONSTRUCTION COST SUBTOTAL |
$2,096,300 |
|||
|
ENGINEERING/CONTINGENCIES (25%) |
$524,100 |
|||
|
TOTAL PROBABLE CONSTRUCTION COST |
$2,620,400 |
TABLE 2-5
ENGINEER’S OPINION OF PROBABLE CONSTRUCTION COSTS
HEBER PUBLIC UTILITY DEPARTMENT
WATER DISTRIBUTION SYSTEM IMPROVEMENTS
|
ITEM
|
QTY |
UNIT |
PROBABLE UNIT INSTALLED COST |
TOTAL
|
|
8" PVC WATER LINE |
9600 |
LF |
$25.00 |
$240,000 |
|
SERVICE CONNECTIONS |
110 |
EA |
$400.00 |
$44,000 |
|
CAST IRON FITTINGS |
4 |
TON |
$6,000.00 |
$24,000 |
|
4" X 4" TAPPING SLEEVE AND VALVE |
6 |
EA |
$1,310.00 |
$7,860 |
|
6" X 6" TAPPING SLEEVE AND VALVE |
6 |
EA |
$1,660.00 |
$9,960 |
|
8" X 8" TAPPING SLEEVE AND VALVE |
1 |
EA |
$2,310.00 |
$2,310 |
|
10" X 4" TAPPING SLEEVE AND VALVE |
4 |
EA |
$2,360.00 |
$9,440 |
|
10" X 6" TAPPING SLEEVE AND VALVE |
3 |
EA |
$2,600.00 |
$7,800 |
|
10" X 8" TAPPING SLEEVE AND VALVE |
1 |
EA |
$3,125.00 |
$3,125 |
|
12" X 8" TAPPING SLEEVE AND VALVE |
1 |
EA |
$3,120.00 |
$3,120 |
|
8" GATE VALVE |
3 |
EA |
$1,100.00 |
$3,300 |
|
CONNECTIONS TO EXISTING MAINS |
1 |
EA |
$4,430.00 |
$4,430 |
|
CONNECT EXISTING F.H. TO NEW MAIN |
12 |
EA |
$1,200.00 |
$14,400 |
|
NEW FIRE HYDRANTS |
36 |
EA |
$3,000.00 |
$108,000 |
|
ASPHALT STREET REPAIR |
1300 |
SY |
$45.00 |
$58,500 |
|
SURFACE REPAIR FOR NON-PAVED SURFACES |
900 |
SY |
$5.00 |
$4,500 |
|
20" DIA. STEEL ENCASEMENT (BORED) |
100 |
LF |
$220.00 |
$22,000 |
|
ISOLATION VALVE REPLACEMENT |
30 |
EA |
$1,500.00 |
$45,000 |
|
PROBABLE CONSTRUCTION COST SUBTOTAL |
$611,745 |
|||
|
ENGINEERING/CONTINGENCIES (25%) |
$152,955 |
|||
|
TOTAL PROBABLE CONSTRUCTION COST |
$764,700 |
TABLE 2-6
ENGINEER’S ESTIMATE OF PROBABLE CONSTRUCTION COSTS
HEBER PUBLIC UTILITY DEPARTMENT
WASTEWATER COLLECTION SYSTEM IMPROVEMENTS
|
ITEM
|
QTY |
UNIT |
PROBABLE UNIT INSTALLED COST |
TOTAL
|
|
8" PVC SEWER PIPE (>-6’ DEPTH) |
847 |
LF |
$37.50 |
$31,763 |
|
10" PVC SEWER PIPE (> 6’ DEPTH) |
2790 |
LF |
$43.00 |
$119,970 |
|
12" PVC SEWER PIPE (> 6’ DEPTH) |
748 |
LF |
$52.00 |
$38,896 |
|
18" PVC SEWER PIPE (> 6’ DEPTH) |
1685 |
LF |
$78.00 |
$131,430 |
|
MANHOLES (0’ – 6’ DEPTH) |
10 |
EA |
$1,500.00 |
$15,000 |
|
CONNECTIONS TO EXISTING MANHOLES |
60 |
EA |
$500.00 |
$30,000 |
|
ASPHALT STREET REPAIR |
6300 |
SY |
$45.00 |
$283,500 |
|
SURFACE REPAIR FOR NON-PAVED SURFACES |
4550 |
SY |
$5.00 |
$22,750 |
|
24" DIA. STEEL ENCASEMENT (BORED) |
300 |
LF |
$175.00 |
$52,500 |
|
NEW PUMP STATION AT PARKYNS AVE. |
1 |
LS |
$37,800.00 |
$37,800 |
|
REPLACE PUMP MOTORS AT 6TH STREET PUMP STATION |
1 |
LS |
$2,250.00 |
$2,250 |
|
|
|
|
|
|
|
PROBABLE CONSTRUCTION COST SUBTOTAL |
$765,859 |
|||
|
ENGINEERING/CONTINGENCIES (25%) |
$191,441 |
|||
|
TOTAL PROBABLE CONSTRUCTION COST |
$957,300 |
Suitability of Proposed Improvement Sites
The site of the proposed plant expansion is ideally suited for this purpose. Sufficient space for the treatment plant expansion exists within the boundaries of the existing facility. As noted on the preliminary construction plans the site can accommodate all of the additional treatment units required. This plant site has been in use for over 60 years and continued utilization of this type will not adversely affect the surrounding area.
The existing raw water basins will continue to be of service to the HPUD. Basins 2 and 3 will be improved with the addition of concrete on their side slopes for wave protection. The bottom of all three basins will be concrete lined to allow easier, more frequent removal of sediment. Interconnection piping between the basins will be installed to improve the operational flexibility of the influent water handling system. The existing finished water storage tanks will remain in service, as will the variable speed high-service pumps delivering water to the system. To the extent possible, the HPUD will continue to use existing equipment and structures.
The areas of new line installation for both the water distribution and the wastewater collection systems are also well suited for this project, as the new lines would be lain adjacent to the existing pipes. This will help to minimize the amount of street repair required for the project.
The project is to be completed in a single phase, with the construction taking place within the confines of the existing plant site. As noted earlier, the expansion consists of the addition of new flocculation/clarification/filtration equipment as well as improvements throughout the plant. Line replacement, both water and sewer, as well as installation of fire hydrants and upgrades to the sewer lift stations, will be accomplished so as to minimize disruption of service to the customers. A half-sized set of 30% complete preliminary construction plans is included in Appendix A.
CONFORMANCE WITH INTERNATIONAL TREATIES AND AGREEMENTS
It is believed that none of the proposed system upgrade projects will affect any international treaties or agreements with either the United States or Mexico.
SECTION 3 - HUMAN HEALTH AND ENVIRONMENT
Human Health and Environmental Need
This project will accomplish the following:
Failure to improve these systems within the HPUD infrastructure can impact human health and environment, as the system problems include:
Therefore, the benefits derived from this project include:
ENVIRONMENTAL ASSESSMENT
System improvements such as those proposed for Heber generally require the completion of the California Environmental Quality Act (CEQA) documentation. Since this project may be partially funded by the U.S. Environmental Protection Agency (EPA) through the NADB, it is also subject compliance with the National Environmental Policy Act (NEPA) requirements.
In response to those requirements, a joint environmental assessment has been conducted on these project sites. A copy of the report, entitled "Environmental Assessment for Class II Action", is included in Appendix B. This document satisfies both federal and state requirements.
This assessment concluded that there are no long-term environmental impacts associated with this project. There were no sensitive areas found within the project areas and the only impacts noted were those associated with construction activities during the project’s installation. These impacts will be minimal and short-term, confined primarily to minor noise and air quality issues associated with construction.
The CEQA analysis was completed and the resulting "Negative Declaration" is enclosed within this assessment. Although the environmental assessment noted no significant impacts from this project, mitigation efforts for two items will be incorporated into the plans and specifications.
These are as follows:
Seismicity
The concern is that strong shaking could damage the treatment plant facilities. The mitigation efforts involve:
Hazardous Materials
The water treatment facility will utilize chlorine gas for disinfection. This gas is toxic and there is a possibility of its accidental release.
Accordingly, the following mitigation measures will be taken:
Based on the joint Environmental Assessment document, the Environmental Protection Agency (EPA) issued a Finding of No Significant Impact on August 30, 1999.
TRANSBOUNDARY ASPECTS
The project is not believed to involve any negative transboundary environmental impacts and will contribute to a reduction of the potential health risks associated with an aging water treatment plant operating at capacity and water distribution system and wastewater collection systems that are undersized and lack sufficient carrying capacity. The entire project lies within the United States.
COMPLIANCE WITH APPLICABLE ENVIRONMENTAL AND CULTURAL RESOURCE LAWS AND REGULATIONS
Regulatory Agencies with jurisdiction over the HPUD Water Treatment Facility, the Water Distribution System and the Wastewater Collection System:
This agency will review and comment on the proposed water treatment plant, water distribution system and wastewater collection system design at 60%, 90% and 100% completion. The DHS will also have the opportunity to evaluate the projects’ impact on the community, the local environment and the human health of the surrounding area.
As part of the environmental assessment, a biological and archeological survey was completed. The biological survey was conducted on April 23, 1999 and concluded that none of the habitats encountered along the alignment of the various routes and work sites contain any significant native flora or fauna. No impacts to biological resources are expected from implementation of the project. The archeological survey was conducted on June 30, 1999 and concluded that there are no prehistoric or historic sites that the proposed project would likely impact. Copies of these documents are included in Appendix B.
The Heber Public Utility Department currently holds the following permit:
A copy of the current permit is in Appendix D. The existing environmental permit currently in force for this facility will apply, with modifications for flow and disinfection requirements, for the new, upgraded plant. The current permit expires at the end of 1999. It is anticipated that an interim permit will be issued to the HPUD until such time as the new plant can be constructed and brought on line. Upon completion of the project, the final permit will be issued.
The contacts for this agency are:
Mr. Roger Berger, Sanitary Engineer or Ms. Toby Roy, District Engineer
Department of Health Services
Drinking Water Field Operations Branch
1350 Front Street, Room 2050
San Diego, CA 92101
Phone: (619) 525-4159
Facsimile: (619) 525-4383
SECTION 4 - TECHNICAL FEASIBILITY
APPROPRIATE TECHNOLOGY
The alternative analyses indicates the construction of a new water treatment facility at the existing site is the most attractive, cost-effective option. Furthermore, the preliminary engineering investigation included computer analyses of both the water distribution system and the wastewater collection system. The water distribution system improvements can be accomplished by increasing the water line sizes as needed to allow the delivery of fire flows throughout the system and by the installation of fire hydrants throughout the older sections of town. Similarly, the wastewater collection system will also be improved with the installation of larger collector gravity lines and upgrades to two sewer lift stations. The 30% preliminary engineering design has been completed and is included in Appendix A.
Water Treatment Facility
One phase of this project focuses on efforts to correct the deficiencies detailed by DHS related to the water plant’s current condition, especially with regard to capacity restrictions and filtration methods being used (Appendix E). The main effort will be to install improvements aimed at maintaining the quality of the treated water produced by the plant, increase the treatment plant capacity and improve the infrastructure of the plant itself.
The technology proposed for use in this project is similar to the treatment system that has been used by the HPUD for the past 25 years. Type of treatment includes chemical addition, clarification, filtration and chlorination. The technology currently in use at Heber, which is similar to that proposed for the plant upgrade, is extremely well recognized as a conventional treatment method and very well suited for this application. It is effective in treating the surface waters received by the HPUD and is appropriate for use there. The plant personnel are very familiar with the operation of this type of facility and its operation and maintenance requirements.
The treatment plant proposed consists primarily of two package treatment units each capable of processing up to 2 (two) million gallons per day. This will ensure that the HPUD can deliver sufficient potable water to the system even with one unit out of service. These units consist of a solids contact section followed by clarification and rapid-sand filtration. The treated water will then be chlorinated and pumped into the large storage tanks at the plant site. The treated water will then be routed to the distribution system in Heber via the high service pumps.
The primary advantages associated with installing a packaged treatment unit are lower unit costs, ease of expansion, ease of operation and smaller area required for installation. As the HPUD system grows, their treatment capability can also expand. Installing two 2-mgd units now will give Heber a minimum of 2 million gallons per day of firm treatment capacity. Should future expansion of the water treatment plant become necessary, another 2-mgd package unit can be installed with a minimum of construction. This would then give HPUD a firm treatment capacity of 4 million gallons per day, which should serve this community into the foreseeable future.
The treatment technology employed by this type of system is well established within the water treatment industry and is acceptable to the California State Department of Health Services. In fact, one of the driving forces behind this water treatment plant improvements project is the State’s requirement that HPUD eliminate their use of pressure sand filtration and move toward gravity driven, rapid sand filtration to produce finished water. These packaged units employ just this type of technology.
Additional improvements to be made at the water treatment plant include the construction of a new finished water lift station. This station will feed finished water flowing from the treatment units to the ground storage tanks. The raw water pumps are to be replaced as well, along with the raw water piping and valves. Both the raw and finished water pumps will be controlled by the water levels in the finished water storage tanks. Other improvements include a new laboratory/maintenance shop at the plant site as well as security fencing around the perimeter of the site. If required by the State DHS, a chlorine scrubber will be installed on the disinfection system at the plant site.
Further improvements involve regrading the eroded inner slopes of raw water sedimentation basins 2 and 3, followed by concrete lining of the slopes for wave protection. In addition, the bottom of all three raw water basins will be lined with concrete to facilitate more frequent removal of the sediment. The connecting pipe network between the basins will be lowered to allow full use of the basin’s depth, especially after the accumulated sediment is removed. The filter backwash will continue to be routed to the existing backwash basin as currently operated.
An emergency backup generator will be installed to power the main high service pumps during electrical outages. This unit will allow the HPUD to continue to supply Heber with potable water even if the power outage lasts for several days. Since the treatment plant itself is currently powered by the existing backup generator, and will continue to be so supplied, HPUD can produce and deliver potable water to the community regardless of a power outage.
The treatment technology proposed for Heber is very similar to that already in place and being used by the District. The technology is used at scores of treatment facilities across the nation and is readily accepted by the regulatory agencies. The existing operations personnel at Heber are familiar with the type of treatment plant being proposed and should have no difficulty becoming familiar with its operation and maintenance with a minimum of training.
The design engineer, upon the completion of the plant’s construction, will prepare an Operations and Maintenance manual. This manual will include data on each of the treatment process units and their operation and maintenance. Also included in this effort will be plant personnel training, as required, to ensure the system is operated properly and as designed.
Water Distribution System Improvements
The approach to improving water distribution is basically to replace those water lines that have deteriorated or failed within the HPUD system. As indicated by the HPUD operations personnel, and confirmed by the flow models employed on this project, those lines that are not capable of delivering adequate flow to the users are to be replaced. This replacement will consist of the excavation of a trench adjacent to the existing pipe and the installation of a new line. The service connections to the adjacent meter will be made to the new pipe and will be implemented to minimize the disruption of service to the user.
The methods and materials used to effect these improvements will be in accordance with the State’s requirements and are appropriate to this application.
Wastewater Collection System Improvements
The improvements to the sewer collection system are similar to those anticipated for the water distribution system, in that undersized collection lines will be replaced with lines that are capable of handling the incoming flows without surcharging the adjacent manholes. The existing lines will be replaced in accordance with good standard practice.
Two pump stations within the collection system are to be improved as part of this project. The sole remaining dry pit pump station will be replaced with suction lift pumps that are similar to those used throughout the District. This type of pump station is easily maintained and is appropriate for this application. The pump motors and drive system in the second station will be modified so that the pump station will have sufficient capacity to handle the incoming wastewater flows.
APPLICABLE DESIGN REGULATIONS AND STANDARDS
The following requirements are being met so that this project may progress.
Contact person for the State Department of Health Services:
Mr. Roger Berger, Sanitary Engineer or Ms. Toby Roy, District Engineer
Department of Health Services
Drinking Water Field Operations Branch
1350 Front Street, Room 2050
San Diego, CA 92101
Phone: (619) 525-4159
Facsimile: (619) 525-4383
OPERATION AND MAINTENANCE PLAN
The operation and maintenance plan for the water distribution system, the water treatment plant and the sewer collection system at Heber is similar to that already operated by the Utility’s personnel. The system improvements use equipment that, while not necessarily identical, is similar in nature and operation to that already in place.
Over the past several years, the water plant was not well maintained. This lack of constant attention gave rise to several items that required repair. An intensified maintenance program was put into place in late 1997 with the hiring of a new general manager. This program originally focused on correcting the most critical items within the plant itself. However, as those items have been addressed, the focus has shifted toward the operation of the facility and the on-going, long-term maintenance of the system components.
Operation and maintenance manuals for each piece of equipment are maintained at the plant site. These manuals contain the specifications and cut sheet drawings for each system component. Additional information includes maintenance schedules for each item and a replacement parts list. The manuals contain a schedule for equipment checkups and routing maintenance that is followed by each operator.
Start-up Operation Plan
Traditionally, both the contractor and the equipment supplier conduct the initial start-up of plant equipment. This helps to ensure that the equipment is installed correctly and that starting the equipment improperly does not void the warranty. This procedure helps protect the Owner (HPUD) from claims by the manufacturer that the equipment was not installed or started up properly.
Detailed information on each piece of equipment chosen for this project will be submitted for review by the project engineer. This is done in the form of shop drawings and determines if the equipment meets the requirements of the specifications. Equipment that does not meet the intent of the specifications is rejected and the contractor is required to submit a suitable unit.
However, some defects in the equipment are not obvious and are thus not caught during the shop drawing review phase of the construction project. These problems will normally become apparent either during start-up or within the warranty period of the equipment. If the equipment fails to operate properly either at start-up or during the warranty period, the manufacturer and the contractor is responsible for removing and replacing the equipment with a satisfactory unit. This work is normally undertaken at no additional cost to the Owner.
If the warranty period has expired for a particular piece of equipment, it is normally the responsibility of the Owner to arrange for its repair and/or replacement, including the costs associated with removing the unit from service.
The construction of the new plant is to be accomplished while the existing plant remains in operation. Prior to the start of construction, the contractor will submit a sequencing plan to the District and the engineer for approval. This plan will account for the continued operation of the current treatment facility and will address any environmental concerns of the construction.
Contingency Plan
The contractor will be required to submit an emergency response and contingency plan upon the issuance of contract award notice. This plan will detail actions to be taken should an emergency arise during the construction or start-up of the plant. This plan will include emergency numbers, contact personnel, and evacuation procedures.
This information will be updated and maintained by HPUD after construction and start-up is completed so that should an emergency occur during normal operation, a response plan is in place and can be implemented quickly. The operations personnel will be trained in emergency response procedures.
Safety Plan
An operational safety program will be developed and implemented for use by all District personnel involved with plant operation or maintenance. This plan will be reviewed periodically for relevance and updated as required for currency. Necessary safety equipment will be obtained and maintained at the plant site for use by the operators.
Quality Assurance Plan
The primary course to ensure that the quality of the project’s output meets the predetermined standards is to review the engineering design. This review would focus on the type of treatment system proposed and the determination that the design is based on generally accepted engineering criteria. The responsibility for this determination lies with the design engineer on the project. As the proposed plant is similar to the existing facility that has operated well for over 18 years, it is reasonable to assume that the new facility, which is based on widely applied technology that has been proven over the years, will operate as required as well.
Pollution Prevention Plan
The only materials normally stored at the plant that could be considered a pollutant would be the chlorine gas used in the disinfection process. This gas is stored in 150-lb cylinders in the chlorine room at the plant. Any concentration of gases that could cause a hazard to the plant operator will trigger an alarm condition within the storage room.
Should a leak occur the ventilation fans located within the storage rooms would operate as designed to dispel the concentrated gases. Given the relatively small quantity of gas contained by the cylinders, once the gas is vented to the outside atmosphere, they should disperse with little risk to the surrounding population. In the event of any type of release, the safety plan outlined above will be implemented and the applicable contingency plan will be activated.
SECTION 5 - FINANCIAL FEASIBILITY
The long-term feasibility of the Heber Water Treatment Plant Improvements Project will be ensured by the subsidized construction of additional treatment capacity. This additional capacity will serve both existing and future customers within the service area.
Financial Statements – Historical
Audited financial statements for the past nine years (1990-1998) are submitted in Appendix H. As required, each contains a balance sheet, income statement, statements of the sources and uses of the funds collected as well as the auditor’s report.
Financial Statements – Pro Forma
Pro forma financial statements with income projections are submitted in Appendix J – Subsection 1. The statements reflect constant values and includes a source and use statement.
Financial Structure of the Project
Table 5-1 below details the amounts of loan and/or grants as well as their source.
TABLE 5-1
PROJECT FINANCIAL STRUCTURE
|
Available Funding |
Amount ($) |
% of Total |
|
Loans |
|
|
|
USDA loan |
1,126,500 |
25.94 |
|
Loans Subtotal |
1,126,500 |
25.94 |
|
Grants |
|
|
|
USDA grant |
1,223,500 |
28.18 |
|
BEIF grant |
1,992,400 |
45.88 |
|
Grant Subtotal |
3,215,900 |
74.06 |
|
TOTAL |
$4,342,400 |
100% |
Capital Improvement Plan
Tables 5-2 and 5-3 below illustrate the capital improvements plan, including both initial capital as well as fixed and variable costs.
TABLE 5-2
PROBABLE OPERATION AND MAINTENANCE COSTS
WATER TREATMENT FACILITY
|
Unit Process or Item
|
Estimated Annual Cost
|
|
|
|
|
Treatment & Disinfection Chemicals |
$10,000 |
|
Supplies |
$12,000 |
|
Repairs |
$15,000 |
|
Salaries, Wages and Benefits |
$76,000 |
|
Power |
$35,000 |
|
Laboratory |
$1,300 |
|
|
|
|
TOTAL |
$149,300 |
TABLE 5-3
ESTIMATED CAPITAL COSTS
WATER TREATMENT FACILITY, WATER DISTRIBUTION & WASTEWATER COLLECTION SYSTEM IMPROVEMENTS
|
Proposed Improvement
|
Estimated Capital Cost
|
|
|
|
|
Water Treatment Plant |
$2,620,400 |
|
Water Distribution System |
$764,700 |
|
Wastewater Collection System |
$957,300 |
|
TOTAL |
$4,342,400 |
Operations and Maintenance Budget – Historical
Copies of the most recent nine-year period (1990-1998) operation and maintenance budgets are presented in Appendix H.
Operations and Maintenance Budget – Pro Forma
The pro forma O & M budgets extending through the term of the loan are found in Appendix J – Subsection 1.
Sensitivity Analysis
Upon receipt of preliminary amounts of loans versus grant monies, various scenarios related to the financing of this project will be developed. These illustrate the impact that changes in interest rates, population projections, inflation, etc. will have on the viability of the project. The most critical variables appear to be the amount of funding from grant sources and secondarily, the prevailing rate of interest used throughout the life of the loan. These scenarios are included in Appendix J – Subsection 3.
Financial Break-Even Analysis
Given the grant and loan amounts from the different funding agencies, the revenue level at which this project will just recover total costs has been calculated. This is included in Appendix J – Subsection 2.
DEMOGRAPHIC AND ECONOMIC INFORMATION OF THE PROPOSED SERVICE AREA
The Community Economic Profile and the 1990 Census data are included in Appendix F. This information is based on the 1990 Heber Census and shows a median household income of $20,306. The township of Heber is included in the Imperial County labor market area, of which the largest industry is agriculture. Based on the October 1998 estimate, the unemployment rate in the county is 30%. Nearby cities of El Centro and Calexico have unemployment figures of 29.1% and 38.7% respectively (data is not seasonally adjusted). As an unincorporated township with a population less than 6,000 at the time of the Census, Heber is not polled individually.
Heber is located within Census Tract 113, which is rural and primarily agricultural. The township of Heber itself covers approximately 800 acres, which is the service area of the existing system. Based on the 1990 Census, Tract 113 had a population of 5,359 persons and the Heber townsite had a population of 2,566. This represents 47.9% of the total population of Tract 113.
Given that the 1990 Census is the most recent available, population projections were based on the Southern California Association of Governments (SCAG) figures, which have been projected for this tract through the year 2020. A similar growth rate was assumed for the Heber Township and it is this basis on which the future population figures are based. The growth rate for Heber between 1980 and 1990 averaged 1.4% annually.
If this same rate is applied to Heber’s population through 1998, the current population would be 2,868 persons. If the 1990 Census Tract 113’s population of 5,359 persons is used along with the SCAG projected population for the area (7,604 persons), the growth rate between 1990 and 2000 averages 3.56% per year. At a starting population for Heber of 2,566 in 1990, the current population would be 3,426 persons. Table 2-2 (shown previously) details these projections.
FEE/RATE MODEL
Historical Fee/Rate Schedules
Refer to Appendix G, which shows the water rate fee schedule for the HPUD. The old rate applied through April 1998, when the latest rate increase took effect. Comparisons between billing and collection indicate the efficiency of collection averages 94 percent.
Pro-Forma User Fee Structure
Analysis will be completed by the NADB and will include an evaluation of the current rate-based revenues from the HPUD’s customers. Using the analysis supplied by NADB, the final rate schedule will be developed.
PROJECT MANAGEMENT
Organizational Structure
The organization chart below (Figure 5-1) for the Heber Public Utility District illustrates the positions of key management and functional department heads, as well as the lines of authority among the positions. These positions include the General Manager, Operations Personnel, Office Manager and Field O&M Personnel.
FIGURE 5-1
HEBER PUBLIC UTILITY DISTRICT
ORGANIZATION CHART

The job functions, responsibilities and lines of communication for each is provided herein. Below is a brief description of the management personnel for the District.
Heber Public Utility District Interim General Manager- Mr. Manuel Castaneda
Line of Communication:
Responsibilities: