National Fuel has an excellent utility system safety record. With more than 14,800 miles of pipelines, our utility system is sizable and complex.
Over the years, advances in materials technologies, such as the improvement of plastic pipe design, have allowed us to further enhance system safety. Just over two decades ago, our utility segment began an ambitious program to accelerate the modernization of its system. Since that time, the company has made remarkable progress, eliminating more than 50% of its bare steel, cast iron and wrought iron mains and more than 65% of its bare steel services across the system. In Pennsylvania, the company has eliminated and replaced all cast iron pipelines.
We have recently accelerated the pace of pipeline replacement. Over the past five years, National Fuel has invested over $299 million in the safety of our utility pipeline network, including replacing approximately 670 miles of bare steel, cast iron and wrought iron utility mainlines. As a result, the company has seen a significant reduction in the number of leaks reported annually.