Readers of San Diego Beer News are hip to the fact new brewing companies are opening at a rapid clip, with a glut of other businesses working their way to their public debut. But the consistent reader is also aware that brewing companies are starting to close with greater regularity than we’ve seen over the past decade, as well. La Jolla Brewhouse, El Cajon Brewing Company and The Brew House at East Lake have all shuttered within the last year alone.

Three businesses might not seem like much, but considering there are only around 70 brewhouses total in San Diego County, it represents nearly five percent of the entire local industry. Throw in Mad Lab Craft Brewing, the Otay Mesa brewery that closed its facility with plans of reopening as a manufacturing-only brewery next year, and that percentage rises. But wait, there’s another local business calling it quits, one that’s the most surprising of all—Rock Bottom Brewery & Restaurant (401 G Street, Downtown).

The brewery restaurant’s 15-year lease is about to expire and Rock Bottom’s parent company, Craftworks Breweries & Restaurants (who also own Gordon Biersch, has decided to close its store rather than renew. The last day of business at that spot will be October 5. Up Interstate 5, Rock Bottom’s award-winning, longer tenured La Jolla brewpub will remain open.

On top of this news, word on the street has it that the owners of Pizza Port are looking to unload their unincorporated brewpub Bailey’s Wood-Pit BBQ> (2307 Main Street Julian). Opened in late 2011, it’s the place of origin for the beers of Julian Brewing Company, which used to be helmed by former Bailey’s partner Tom Nickel, but has been helmed by Pizza Port’s Mike Gabbard and co-owner Vince Marsaglia since Nickel’s departure.

It should be noted that all of the closed or shutting down businesses mentioned in this article are brewpubs, restaurants with on-site brewing facilities. Certainly, the model itself can work in San Diego. The quartet of Pizza Port’s in San Diego are busy and some have been named the best of their kind in the country. Karl Strauss Brewing Company's brewery restaurants do well, and the newly opened Stone Brewing World Bistro & Gardens – Liberty Station is selling plenty of its house beers. It would seem the small, single outposts are the ones having trouble.

Craft beer fans talk all the time about market saturation and bubbles bursting. Could the first example of this be found in the brewpub sub-sect of the industry? Are there too many businesses for a smaller or newer operation to survive amid larger, more established and successful contemporaries?

Disclosure: In addition to his work as a journalist, Brandon Hernández is employed by Stone Brewing Co.