What: Shares of energy companies Plains All American Pipeline, L.P. (PAA 1.41%) and its general partner Plains GP Holdings LP (PAGP 1.57%) dropped 11% and 20%, respectively, after they gave investors a disappointing view of the future.

So what: Plains All American Pipeline's revenue for the second quarter dropped 40% to $6.7 billion and net income fell by 57% to $124 million. Adjusted net income per share for Plains All American Pipeline was $0.27, which fell $0.02 below estimates.  

The real news today was that the All American pipeline in California isn't going to return to service until 2016, which will reduce the company's earnings for the year. Full-year EBITDA guidance was lowered by $50 million to a midpoint of $2.275 billion, and that disruption is what investors are focused on today.

Now what: As the general partner and owner of incentive distribution rights, Plains GP Holdings LP has a leveraged interest in Plains All American Pipeline's performance, so it's no surprise the stock is down big today. As for operations, the falling expectations for EBITDA and declines in net income have to be a concern for investors. Oil markets are in turmoil, and while transportation and infrastructure companies may not feel the pain of low prices like drillers do, the glut of inventory that's driving low prices will be a detriment for companies like Plains All American Pipeline for the foreseeable future as well.