Border Environment Cooperation
Commission
Water and Wastewater System Improvements in Douglas,
Arizona
1.
Type of Project.
The project consists of the rehabilitation and
expansion of the existing water and wastewater lines.
2.
Location of Project. The City of Douglas is located in Cochise County,
Arizona, about 105 miles southeast of Tucson. Douglas is bounded by Agua
Prieta, Sonora to the South.
The project is located within the 100 km border region as defined by the La Paz
agreement. According to City estimates, the population in August 2000 was
17,000. In addition, the population in the surrounding areas are estimated at
5,500. The project considers a total project population of 22,500, expected to
reach 25,300 by the year 2006, and 33,400 by the year 2020. The city has a
water consumption of 102 gallons per capita per day (gpcd) for residential
areas and 128 gpcd for the overall city average.
3.
Description of Project and Tasks. The
project considers the installation and rehabilitation of approximately 55,795
linear feet of water lines and 83,770 linear feet of sewer lines.
4.
Compliance with International Treaties and
Agreements. There are currently no international
treaties or agreements in place between Agua Prieta, Sonora and Douglas,
Arizona regarding wastewater discharge volume or quality, except the general
agreements between both sections of the International Boundary and Water
Commission, including Minute 261 and the Treaty of 1944. The project complies
with these agreements. Also, the City of Agua Prieta has asked the City of
Douglas not to chlorinate the effluent. This request is fulfilled by the City
of Douglas.
1.
Human Health/Environmental Needs. Deteriorated sanitary sewage collection lines and failing septic tank
systems, coupled with deficient water distribution system, prompted the City of
Douglas to take action in order to improve and solve these conditions. Thus,
the primary objective of this project is to improve the health and well-being
of the residents of the City by improving its aging infrastructure associated
with the water distribution system and wastewater collection network. These
systems have experienced a series of problems associated with water quality,
leaky sewer lines, and substandard on-site sewage treatment units. Thus, the
replacement and rehabilitation of the deficient water lines and the expansion
of the sewage collection service area to address current needs will promote a
healthier community.
2. Environmental
Assessment. An environmental
assessment was prepared for the project by Science Applications International
Corporation (SAIC) under contract to the U.S Environmental Protection Agency
(EPA) Region IX. Also, CDM prepared a supplemental Environmental Assessment
(EA) to discuss the impacts of projects that were not considered in the
original EA. According to the EA, the project does not have any significant
environmental impacts. Consultation with Arizona State Historic Preservation
Office and 4 Arizona Indian tribes has been completed.
3.
Compliance with Ecology and Cultural Laws and
Regulations. EPA reviewed the
environmental assessment and submitted their finding of no impact on April 20,
2001. The EA considered any and all cross-cutting environmental and
cultural/historical laws, Executive Orders and regulations, including among
others, Significant, Unique or Important Farmlands, National Natural Landmarks,
Wilderness Protection, Wild and Scenic Rivers, Wetlands Protection, Floodplain
Management, Fish and Wildlife Protection, Endangered Species Protection,
Historical, Archaeological, and Cultural Sites, Air Quality, and Environmental
Justice. The project is in compliance with all applicable environmental and
cultural resource laws and regulations, assuming all future consultation,
mitigation, and observance of restrictions are followed.
1.
Appropriate Technology.
The proposed facilities adhere to technologies widely accepted and proven in
the United States. The existing wastewater collection system of the City of
Douglas consists of a gravity-fed network. The proposed sewer improvements will
be congruent with this system. The proposed pipe material is polyvinyl
chloride. Hence, no additional training will be necessary for City staff to
operate the proposed works.
An adequate level of
engineering design has been achieved for the proposed sewer lines. Overall, the
project includes the construction of 83,770 linear feet of sewer pipeline and
over 170 manholes and fittings.
The existing water
distribution system consists of two pressure zones, with asbestos-cement and
cast-iron pipe sizes ranging from 3-inches to 18-inches in diameter, 6 wells,
one pressure relief valve, four reservoirs, one abandoned booster station, and
four abandoned wells. The proposed pipe material is polyvinyl chloride (PVC).
The task encompasses 55,795 linear feet of pipeline, rehabilitation of a booster
station, and one pressure reducing station.
A
parallel project, though not part of the certification is the rehabilitation
of the wastewater treatment plant. The
proposed 2.6-mgd plant upgrade for the City of Douglas utilizes a treatment
technology widely accepted and proven in the United States. One relevant factor
about upgrading the facility is that operations personnel are considerably
familiar with the process. This technology has been used in the Douglas Plant
since 1978, with some minor adjustments that were required to comply with
discharge standards. The main purpose of the project is to improve the quality
of the effluent being discharged into Agua Prieta. The anticipated new
technology contemplated within the upgrades is the construction of the
chlorination/dechlorination system.
The
upgrade of the treatment plant consists in the rehabilitation of the following
unit processes: inlet parshall flume, aerated grit remover, comminutor,
extended aeration basins, secondary clarifier, outlet parshall flume, chlorine
contact chamber, and sludge beds.
2.
O&M Plan.
Prior to start-up, training on the operation and maintenance
(O&M) of the Supervisory Control and Data Acquisition (SCADA) System will
be conveyed to the city operations staff by the equipment supplier. O&M
training will also be offered to personnel on the booster and pressure reducing
stations. For the sewer and water lines, no additional training will be
necessary, since the same methodologies that are being applied to the existing
system can be applied to the new system.
3.
Compliance with applicable design norms
and regulations. The preliminary design of the facilities, completed
as part of the certification process, was performed following common
engineering practices and reference manual. In particular, the water and
wastewater pipeline design and SCADA system were performed following ADEQ
Bulletins 10 and 11.
Financial Feasibility and Project Management
1. Financial
Feasibility.
The NADB completed the financial analysis to
determine the funding structure of the project and the user rates to guarantee
the financial sustainability of the operating agency.
|
Estimated Cost |
|||
|
Concept |
Amount (US$) |
||
|
|
|
Water system improvements |
2,976,194 |
|
|
|
Wastewater system improvements Hook-ups |
3,861,807 620,212 |
|
|
|
Mobilization, testing and traffic control Contingencies (15%) |
240,000 1,154,731 |
|
|
|
Total |
$8,852,944 |
|
Current Water and Wastewater Expenses (Annual) |
|||
|
Concept |
Amount (US$) |
||
|
|
Water Office Water Field Wastewater Fund |
323,750 1,013,440 514,993 |
|
|
|
|
TOTAL |
1,852,183 |
Financial Structure
|
Source |
Amount (US$) |
% |
|
USDA-Rural
Development |
1,810,993 |
20.5 |
|
BEIF |
3,501,850 |
39.5 |
|
City
of Douglas |
1,540,101 |
17.5 |
|
City
of Douglas Loan/Bond |
2,000,000 |
22.5 |
|
Total |
$ 8,852,944 |
100% |
2.
Rate Model: The City of Douglas approved a capital improvements surcharge in
1999. The surcharge will increase by $2 every year for a period of 5 years.
The user
rates, including the surcharge, for the next seven years are presented in the
table below.
|
SINGLE
FAMILY RATES (US$) |
|||
|
|
2000 |
2001 |
2002 |
|
Average Monthly Water Bill |
$ 17.90 |
$ 18.90 |
$ 19.90 |
|
Average Monthly Sewer Bill |
$ 10.12 |
$ 11.12 |
$ 12.12 |
|
|
2003 |
2004 |
2007 |
|
Average Monthly Water Bill |
$ 20.90 |
$ 21.90 |
$ 21.90 |
|
Average Monthly Sewer
Bill |
$ 13.12 |
$ 13.12 |
$ 13.12 |
3. Project
Management. The City has established
a surcharge to the user fees to pay for capital improvements and the creation
of reserves. The City has adequate personnel to handle the proposed
infrastructure and to respond to any potential emergency that might arise
during operation and maintenance of the project.
Comprehensive Public Participation
Plan. The
City of Douglas submitted a public participation plan (plan) to BECC on August
31, 2000. The plan was based on the BECC public participation guidelines and includes
the required criteria elements for certification. Activities carried out thus
far in fulfillment of the plan are summarized below.
Steering
Committee: The steering committee
included Mr. Frank Zepeda, Arizona Public Service Co.; Mr. John Sproule , Southwest Gas; Mr. Jesse Santana, Douglas
School District; Mr. Joe Ruterman, Ram Realty; Mrs. Ana Bernal, Bank One; Mr.
Howard Henderson, KDAP Radio Station; Mr. Rob Johnson, Retail Trade; Mr. Mike
Palmer, Cochise County; Mayor Ray Borane and City Council representatives. The
committee was formed in October 1999.
Local Organizations: The sponsor contacted approximately 25 local
organizations including the Pirtleville and Sunnyside Fire Districts; the
Douglas Unified School District; Catholic Community Services; Douglas
Historical Society and others. Sixteen letters of
support for the project were received, including the American Red Cross, the
Mexican Consulate in Douglas, Compañeros, and the Douglas Public Housing
Authority.
Public
Information: The Step II document was available at the Douglas City Hall Public Works Department; the
Cochise County Board of Supervisors Office (In Bisbee, AZ); and, after work
hours, at the Douglas Public Library.
Additionally, fact sheets were available at the Douglas Water
Department, Gas Company, and Electric Company. The
Mayor of Agua Prieta, Sonora, Irma Villabos de Terán, was informed of the
project by a personal visit from Douglas Mayor Mr., Borane on September 22,
2000. The Agua Prieta Mayor expressed support for the project. Letters of support have been provided by local citizens.
Public Meetings: BECC required
public meetings were held on October 16 and October 23 2000. These meetings
covered the technical and environmental aspects of the project as well as project
costs.
1.
Definition and Principles. The project complies
with BECCs definition of Sustainable Development: An economic and social
development based on the conservation and protection of the environment and the
rational use of natural resources, but considering current and future needs, as
well as present and future impacts of human activities.
The
water and wastewater system improvements project is centered on providing an
improved quality of life for human beings.
The
project provides environmental protection by replacing lines that have frequent
leaks, and also by eliminating the use of faulty septic tanks.
Stakeholders
for this project include the City Council, City departments that plan and
operate the water and wastewater systems, the residents and business that will benefit from the
infrastructure improvements, those who will be impacted by the construction
activity, and supportive state and federal agencies such as Rural Development
and the Arizona Department of Environmental Quality. A Steering Committee
comprising members of the general public was formed for review and
recommendations on the project.
2. Institutional
and Human Capacity Building. An aspect
of this project that will build institutional capacity is the creation of
reserves for any potential emergencies.
3. Conformance
with Applicable Local/Regional Conservation and Development Plans. The
project arose as part of the Master Plan developed by the U.S. Army Corps of
Engineers. Also, the water and wastewater improvements are consistent with the
Citys General Plan.
4. Natural
Resource Conservation. This
project will likely create an incremental benefit by extending the groundwater
supply through replacement of deteriorated pipes, and also by preventing
aquifer pollution due to leaks in existing septic systems.
5.
Community Development. Without the water and wastewater improvements, a
number of negative impacts to the community will continue, hindering community
development.
8.
Concurrence letters
from the Arizona State Historic Preservation Office, and the Tohono OOdham,
Hopi, Gila River, and Ak-Chin Indian Tribes