The MPRP is a program of Central Maine Power Company (CMP), created to study the future needs of Maine’s bulk power transmission system and develop solutions to ensure that the transmission system continues to operate reliably.

CMP invests many millions of dollars annually to maintain and operate the existing transmission system across Maine to meet the needs of its customers. In order to ensure long-term reliability, CMP must carefully plan for the future and make appropriate investments in basic transmission infrastructure in order to maintain the required level of reliability.

CMP’s 345kV transmission system was built and put into service in 1971 and has served the area well for nearly 40 years. Maturing infrastructure and growing electric power needs over the last four decades have raised power quality and reliability concerns for the future. CMP and the Independent System Operator for New England (ISO-NE) have identified certain needs for the transmission system which must be evaluated and addressed to ensure that this system can continue to serve the area well in the future.

The MPRP study is managed by CMP in coordination with ISO New England (ISO-NE) and other utilities.

CMP is a member of ISO New England (ISO-NE), the Regional Transmission Operator (RTO), serving Maine, Connecticut, Massachusetts, New Hampshire, Rhode Island and Vermont. ISO-NE operates New England's bulk electric power system and oversees the regional bulk power market. ISO-NE has lead responsibility for the reliability of the region's bulk electric supply, including meeting reliability standards set by the North American Electric Reliability Council (NERC) (www.nerc.com) and the Northeast Power Coordinating Council (NPCC) (www.npcc.org).

The MPRP study is governed by ISO-NE planning procedures and any significant modifications, upgrades or additions to the CMP transmission system must be approved by ISO-NE and the Maine Public Utilities Commission. Additional information on the ISO-NE planning process and study procedures is available at www.iso-ne.org.

Transmission lines carry bulk electricity from generating plants to areas where a considerable amount of electricity is needed. From there, distribution lines carry electricity to where it is used. The interlocking system of power lines, typically 115,000 volts (115kV) or higher, is commonly referred to as the bulk power system or grid. The bulk power system is comparable to the Interstate Highway System and major state highways, providing a high-capacity and efficient path to move large amounts of electricity to consumers.

Transmission system studies and periodic upgrades are critical for maintaining system reliability and complying with the reliability standards of the North American Electric Reliability Corporation (NERC) and the Northeast Power Coordinating Council (NPCC).

Each year ISO New England (ISO-NE) prepares a comprehensive Regional System Plan (RSP) that includes forecasts of future electric power needs and how the system can reliably meet that demand. The 2006 Regional System Plan (RSP06) documented needs in Maine’s bulk power system, which required further study to identify alternatives and improvements to maintain system reliability.

The MPRP study (“Needs Assessment”) identified system needs to meet basic transmission reliability standards. The MPRP study includes a detailed assessment of Maine’s bulk power transmission system using computer modeling to analyze the 345kV and 115kV system under many scenarios of operating conditions. The study is based upon a ten year load forecast (2017) to determine the effects on the transmission system and evaluate different cost-effective solutions to ensure system reliability over the next decade and beyond.

Additionally, the MPRP separately studied alternatives to potential transmission system solutions, including energy conservation, energy efficiency, Demand Side Management (DSM) and distributed generation. (Read the Non-Transmission Alternatives study)

While the current system is operating reliably today, the MPRP study indicates that major investments in the transmission system are needed by the year 2012 to respond to growing needs for electric power and to ensure a reliable supply of electricity for Maine’s homes and businesses (Read the Executive Summary study) If these investments are not made, the system will become unreliable and greatly increase the risk of major blackouts within the next decade.

CMP has selected a transmission solution to address the needs of the Maine system. The solution consists of several major elements, including:

1. New 345 kV line from Orrington to Cumberland
2. New 345 kV line from Gorham to Newington (Portsmouth), NH
3. New 115 kV line from Windsor to Orrington
4. New 115 kV line from Lewiston to Rumford
5. New 115 kV line from Windsor to Warren
6. Movement of existing 345 kV transmission lines on double circuit towers onto separate towers along the Midcoast
7. Construction of new substations in Benton, Lewiston, and Cumberland
8. Upgrades to substations in Gorham, Kennebunk and elsewhere
9. Upgrades, re-rates, or reinforcement of other 115kV lines

CMP and ISO New England studied a wide range of potential transmission solutions to address the reliability needs of the system.

The MPRP Study Group conducted technical evaluations to assess how the possible combinations of transmission projects would perform during normal, peak, and possible outage scenarios and how those options would support future flexibility. More than 250,000 performance scenarios were evaluated. The study identified 10 transmission alternatives, in various combinations, as possible solutions. CMP has selected a transmission solution based on a number of factors, including electrical performance, cost effectiveness, impacts to landowners and Maine's environment, and robustness under various forecasts of future conditions.

Also, the MPRP studied potential non-transmission alternatives, such as energy conservation and efficiency programs, as possible substitutes for, or to delay building new transmission lines (Read the Non-Transmission Alternatives Study). The findings of this study were weighed and factored into the final proposed transmission solution, which was submitted on July 1, 2008, to the Maine Public Utilities Commission for review and approval.

New transmission lines will be constructed over existing power line corridors (right-of-ways), however, some corridors will have to be widened to accommodate the new lines, especially along routes in central Maine. CMP estimates that it will need to purchase or acquire rights to approximately 550 parcels of land, typically 15 to 100 foot strips along the boundary of its existing right-of-way. Additionally, land will be acquired to build or expand substations.

CMP will negotiate with public and private landowners to buy the necessary land or rights. That process includes a number of notifications, requests, and negotiations with property owners along the proposed routes. CMP believes in paying fair market value for land and is committed to working with landowners to achieve the best estimate of that value. CMP has prepared a pamphlet for landowners and neighbors (PDF, 2MB).

CMP estimates that the Maine Power Reliability Program will cost approximately $1.5 billion, but the company expects that Maine utility customers will pay only a small portion of that.

CMP is a member of ISO New England (ISO-NE), which operates the region’s bulk power system and oversees the regional bulk power marketplace. Under the ISO-NE tariff agreement, most bulk transmission projects are considered regional investments and, accordingly, are designated Pool Transmission Facilities (PTFs). The costs of construction and maintenance of PTFs are shared with other participating New England utilities and their customers. Under the current ISO-NE formula, CMP customers would bear approximately 8 percent of eligible program costs. The remaining 92 percent will be born by ratepayers in the other five New England states.

The MPRP will require a Certificate of Public Convenience and Necessity from the Maine Public Utilities Commission. The proposed transmission projects will also require permits from the Maine Department of Environmental Protection (DEP) under the Site Location of Development Law and the Natural Resource Protection Act. Additionally, municipal permits will be needed in about 80 local jurisdictions.

CMP has taken significant steps to avoid or mitigate impacts on Maine’s environment. CMP has chosen to use existing transmission corridors (right-of-ways) wherever possible to help avoid environmental and community impacts associated with new transmission corridors.

Significant vernal pools have been identified and mapped by biologists and wetlands have been likewise located and catalogued. Additionally, expert consultants have surveyed the proposed routes for endangered and threatened species of plants and wildlife. Based on this information, MPRP design engineers and environmental experts are working closely together to avoid or minimize the impact of transmission structures and substations on wildlife, flora, land and water.

EMF refers to the electric and magnetic fields produced through the generation, transmission, and use of AC (60 HZ alternating current) electric power.

We encounter EMF throughout our daily activities at work and at home. Sources of magnetic fields in our homes include fields generated by appliances, the wiring that powers those appliances, the distribution lines that supply electricity to the home, and any currents flowing on water pipes. Nearby transmission lines may also be a source of magnetic fields in the home but their contribution depends largely upon the distance from the home.

Some people have expressed concern that exposure to EMF might adversely affect human health. In response to these concerns, the National Institute of Environmental Health Sciences (NIEHS) has conducted numerous studies and a major review of research to evaluate the potential effects of EMF on human health. In June 1999, the NIEHS reported to the U.S. Congress that scientific evidence for an EMF-cancer link is weak. The following are excerpts from the report: “The NIEHS believes that the probability that ELF-EMF exposure is truly a health hazard is currently small. The weak epidemiological associations and lack of any laboratory support for these associations provide only marginal, scientific support that exposure to this agent is causing any degree of harm.”

In June 2007, after more than ten years of study the World Health Organization (WHO) released a review of research on EMF and health. The conclusions of this report are consistent with previous review of NIEHS and other national and international agencies. Like NIEHS, the WHO reported that there is a weak statistical association between childhood leukemia and average exposure to magnetic fields at levels above 3-4 milligauss in some studies. But, they also reported that no consistent adverse health effects, including cancer, had been reported in animals, even after exposure to high levels of EMF or that a mechanism to explain any adverse effect had been identified. Based on this review, the WHO concluded that the research does not establish that exposure to magnetic fields causes or contributes to any disease or illness and that electric fields pose no substantive health issues at levels generally encountered by the public. The WHO suggested that engineering practices to reduce EMF exposure from equipment or devices should be considered, provided that they yield other additional benefits, such as greater safety, or involve little or no cost.

60 Hz EMF is not regulated by the State of Maine and at the current time there are no federal standards for occupational or residential exposure to 60 Hz EMF. Nevertheless, CMP and PSNH will consider the guidance from the WHO on this matter.

Consult the following organizations for more information:

World Health Organization, International EMF Project
http://www.who.int/mediacentre/factsheets/fs322/en/index.html

U.S. National Institute of Environmental Health Sciences
Electric & Magnetic Fields http://www.niehs.nih.gov/health/topics/agents/emf/
Download NIEHS EMF Q&A (PDF) http://www.niehs.nih.gov/health/docs/emf-02.pdf

U.S. National Cancer Institute
http://www.cancer.gov/cancertopics/factsheet/Risk/magnetic-fields

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