Hey there,
I think anyone would be naive to think that any dividend is 100% safe - especially with companies that have high debt loads in a rising rate environment. That said, ENB had a dividend above 8% at one point a couple of years ago and still managed to raise the dividend. For a pipeline like ENB, you want to ensure it has sufficient cash flow to maintain interest payments and sustain that dividend.
In Enbridge's case, they have two targets that are of note here. They aim for a dividend payout ratio between 60-70% of distributable cash flow (DCF) and for net debt to be between 4.5-5.0x debt to ebitda. It exited last quarter with a leverage ratio of 4.6x (lower end of target) and Q1 payout ratio came in at 56%. From those two metrics alone, they are doing well. If you look at interest paid, it did jump by 26% YoY to $926M but it still only accounted for 29% of DCF. Combined, the interest + dividend payments accounted for 85% of DCF. This is also an imperfect calculation because DCF already strips out interest payments and stems from Adjusted EBITDA. That said, I like to include back in as a measure of safety. So far, it remains in a decent position. Also worth noting that the company can have up to 30% of its debt as floating rate debt, it employs an interest rate swap strategy to mitigate the impact of rate hikes. Likewise, only 5% of their current debt is floating and exposed to interest rate hikes. That said, it still impacts them.
All in all, this isn't an AQN situation where the interest payments on their floating rate debt got to a point where they couldn't sustain their dividend with cash flows. Their floating rate debt also exceeded 25% of total debt load which was extremely high. This is why they cut the dividend - not to mention that their yield was astronomical. We aren't there yet with Enbridge and I'm not all that worried. That said, if you do the quick analysis I just did posted above every quarter - it may give you peace of mind to see how it fluctuates quarter over quarter. Or, it may also get worse and you'll be better prepared to make a move should you feel the need.
Hope that helps!
Mat