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Mailing Address:  P. O. Box 2265, Granby, CO 80446-2265
Office:  97 Forrest Drive, Granby, Colorado
Tel: 970-887-3759 ∙ Cell:  307-760-2922 ∙ Cell: 307-760-6890
e-mail:  pedersenplanning@gmail.com

Project Experience

Location: Islands of Tutuila, Aunuu and Manua Group, American Samoa
Client: American Samoa Power Authority
Pago Pago, American Samoa  96799
Contact: Mr. Mike Dworsky, USEPA Construction Grants Manager
Year Completed: 2001
Project Scope:

The American Samoa Power Authority (ASPA), a quasi-public utility agency, is responsible for the management, operation, and maintenance of American Samoa’s water, wastewater, power and solid waste systems.  In order to secure U.S. funds for various water system improvements, the ASPA Water Division is required to periodically prepare a water facilities plan and related environmental assessment for the U.S. Environmental Protection Agency (USEPA), Region 9.  In view of PPC’s extensive experience in American Samoa, PPC was retained to prepare an environmental assessment of ASPA’s water facilities plan for the 2001-2015 period.

The proposed water facilities plan program included 14 water system projects.  New transmission line, water storage, and distribution system projects were identified for the extension of the primary water system to several villages relying on surface water systems for their potable water supply.  The development of new satellite water systems was recommended for the remote village of Afono since connection to the primary system was not feasible.  Proposed groundwater well development projects were also identified for the Island of Tau where salt-water intrusion had impacted the quality of existing groundwater well supplies.  System management projects reflected ASPA’s desire:

  • to perform periodic hydraulic modeling of its primary water system.
  • the application of SCADA systems to monitor wells, storage tanks, and transmission systems.
  • to establish operation and maintenance program for new water treatment plants.

Since the environmental assessment was developed for ASPA’s overall water facilities plan, PPC examined four general approaches to future water system delivery.  These options included:

  • continued use of village water systems that rely upon surface water supplies
  • the construction of roof catchment systems on buildings that cannot be feasibly connected to the primary water system
  • development of independent satellite water systems for villages that cannot be feasibly connected to the primary water system
  • extension of primary water system to villages that presently operate and maintain village water systems.

The direct and indirect consequences of the construction of groundwater production wells, water storage tanks, as well as transmission mains and distribution systems, were evaluated in terms of physical land alterations, potential soil erosion, and sedimentation of local streams.  Specific mitigation measures were recommended for project and cumulative impacts.

The impacts of increased water demands, groundwater well production, and withdrawals from basal aquifers were also analyzed.  This analysis quantified anticipated water production requirements and assessed the sustainability of groundwater resources to support anticipated groundwater production.   Anticipated reductions in the hydraulic capacity of the primary water system were also examined.  Future water storage needs were identified for 8 water districts.  Specific mitigation measures were again recommended for project and cumulative impacts