a decrease of $3 million in operating expenses primarily due to the timing of project related expenses of $3 million, lower allocated expenses and lower capitalized overhead of $2 million, partially offset by higher outside services and employee expenses of $2 million; and
an increase of $4 million in Adjusted EBITDA related to unconsolidated affiliates due to two new joint venture pipelines placed in service in 2017; partially offset by
a decrease in transportation fees of $14 million due to renegotiated contracts resulting in lower billed volumes, offset by increased margin from optimization activity recorded in natural gas sales and other.
Interstate Transportation and Storage
Three Months Ended
Natural gas transported (MMBtu/d)
Natural gas sold (MMBtu/d)
Operating expenses, excluding non-cash compensation, amortization and accretion expenses
Selling, general and administrative expenses, excluding non-cash compensation, amortization and accretion expenses
Adjusted EBITDA related to unconsolidated affiliates
Segment Adjusted EBITDA
Distributions from unconsolidated affiliates
Transported volumes reflected increases of 157,060 MMBtu/d on the Trunkline pipeline as a result of increased backhaul deliveries, 153,401 MMBtu/d on the Tiger pipeline due to an increase in production in the Haynesville Shale, and 142,207 MMBtu/d on the Transwestern pipeline as a result of weather driven demand in the West and opportunities in the Texas intrastate market. The remainder of the increase was primarily due to the Rover pipeline, which was placed in partial service on August 31, 2017.
Segment Adjusted EBITDA. For the three months ended September 30, 2017 compared to the same period last year, Segment Adjusted EBITDA related to our interstate transportation and storage segment decreased due to the net effect of the following:
a decrease in reservation revenues of $16 million on the Panhandle, Trunkline and Transwestern pipelines and a decrease of $3 million in gas parking service related revenues on the Panhandle and Trunkline pipelines, primarily due to lack of customer demand driven by weak spreads and mild weather. In addition, revenues on the Tiger pipeline decreased $3 million due to contract restructuring. These decreases were offset by $10 million of revenues from the placement in partial service of the Rover pipeline effective August 31, 2017; and
an increase in operating expenses of $3 million primarily due to higher ad valorem taxes resulting from higher valuations; offset by
an increase in income from unconsolidated joint ventures of $9 million primarily due to a legal settlement and lower operating expenses on Citrus.