مَا أَغْلَقْنَاهَا حِرْمَانًا لَكُمْ.
We did not close it in order to deprive you.
The modifier ḥirmānan places the alleged motive in focus. In this discourse the speaker may be denying the intention to deprive, not every temporary closure or suspension. The next clause can make clear that pumping was stopped for a limited period.
If the intended message were that no closure of any kind occurred, a more explicit unqualified denial would be needed. The relation between negation and its contextual qualification must be reconstructed; otherwise a narrow denial is wrongly inflated into a universal one.