"existing supplies" is correct and usable in written English.
You can use it to refer to supplies that are currently available or exist at the present time. For example, "We need to replenish our existing supplies before the weekend rush."
Stricter conservation measures, like mandating more efficient washing machines, would easily wring more water from existing supplies, critics say.
A SABMiller spokesman said the company had taken "the difficult decision" to start winding down operations in the capital, Juba, when existing supplies of ingredients run out.
Fortunately, I don't have to wait until fall to increase my existing supplies; I can go right out and divide the clumps.
Ms. Carter said consumers would start seeing the new ingredient over the next few months as existing supplies of Gatorade sell out and are replaced.
This left Gazans in long lines on Monday to load up on gas and food in fear of soaring prices once existing supplies are exhausted.
But for all its symbolism and ceremony, this meeting has quite limited goals: seeking ways to better secure existing supplies of bomb-usable plutonium and highly enriched uranium.
A team of colleagues from TNT Express collaborated with slum residents to study existing supply chains.
His existing supply, his brother Rezan says, "will run out in about two weeks.
If the water supply was posing health risks, surely the existing supply should have been repaired or upgraded?
At the current rate of home sales, it would take about 11.2 months to absorb the existing supply.
This approach – focusing on existing supply (and how to make better use of it) as well as demand is welcomed.
