In the early 1990s, the Water Authority received 95 percent of its water from a single source — the Metropolitan Water District of Southern California — making the region vulnerable to supply shortages. In February 1991, worsening drought conditions forced MWD to cut deliveries to the San Diego region by 31 percent. The cutbacks lasted for more than a year, prompting local business and community leaders to ask the Water Authority why it depended on a single source for virtually all of its water. Since then, the Water Authority has aggressively diversified the San Diego region’s water supply portfolio to ensure reliability. Today, the region relies on MWD for about 40 percent of its supplies.