Hi Carolyn - We share your concern, and for the first time since 2007, we received our first "Anchor Slip" Notifications while "off the boat" this last season, and the early warning turned out to be critical as we were anchored in a very busy bay.
We use Maretron's N2KView to monitor the entire boat, and it includes a sophisticated anchor management solution that enables extreme precision if desired.
Several Garmin boaters I know have N2KView integrated into their systems. If that is your case, then you already have a solution that will communicate to you remotely. This remote connection is limited to email unless you have or add an SMS200 to your system to enable N2KView to send SMS messages. Alternatively, and for the price of a cup of coffee, you can turn any email that your boat (or your home) sends into a notification using an app called Pushover (no subscription required). We use this to selectively turn email sent by our monitoring system (N2KView) and our boat's fire and security system into critical notifications that can't be suppressed or silenced until acknowledged. We also use this to send the same from our home.
Because these anchor related notifications are generated from alert-generated emails that I author, they report as much data as desired. So rather than just being told the "Anchor is dragging" - our notifications include details like:
What was the original anchor depth, scope, and rode length?
What is our drag radius currently set at?
How far beyond the radius did we "slip"?
Is the boat still beyond the drag radius or did it bounce back inside?
What was the wind speed and direction when the Slip was triggered?
IMHO, the more data to analyze, the better as to the urgency of the situation.
I also have a notification to let us know that the boat is back in the original radius - suggesting that perhaps our radius was set too tight or our drop position was not captured precisely as desired and we are "bouncing over line".
With N2KView, I am able to remotely expand the drag radius and essentially start over with a wider drag radius.
While this is irrelevant, of course, if you don't have N2KView. You may find the PushOver App helpful for other notification generating purposes.
Carl Gulledge
MV Ellipsis (S-5906)