There are many caterpillars that feed on oak and other trees. The most common ones in the spring are oak leaf rollers, cankerworms, forest tent caterpillars and tussock moths. You could expect perhaps 30 or more other species on oaks in Texas. There is no magic way to prevent insect population outbreaks forever. There will be some caterpillars every year and some of them may be more abundant than you want in your landscape.
There are many chemicals that can control them. In sensitive areas you may want to use a Bacillus thuringiensis product such as Dipel, Thuricide, Worm Killer, or whatever the locally available brand is in your area. These BT products are specific to caterpillars and they are very safe around humans and pets. Be sure to treat early in the season before the caterpillars are large. Smaller caterpillars are easier to control and the large caterpillars cause the most problem.
As the trees get older and larger they will be more difficult for homeowners to reach the tree tops with spray equipment. You will have trouble with coverage when the trees are large so plan to hire a tree service or landscape company who have the equipment to treat the tree tops.
Another alternative is to prune the tree, cover the pool, or find some other solution for the few weeks in the spring when the caterpillars are most common.