Saved up for a rainy day
The phrase "poured down the drain" typically refers to wasting something valuable, such as time, money, or effort. To counter this concept, one could use the expression "saved up for a rainy day," which means to set aside resources in preparation for future difficulties. Another antonym could be "put to good use," indicating that the value of something has been maximized by using it for a beneficial purpose. Similarly, the phrase "invested wisely" implies that resources have been used judiciously and with good foresight. Overall, antonyms for "poured down the drain" emphasize the importance of prudence, resourcefulness, and effective management of resources.