The city of Fond du Lac’s water payment portal is back on line, about a month after a local credit union notified the city that the system had been hacked. On December 12 the credit union said about 25 customers that used the portal had reported fraud on their credit cards. City officials say as of January 15, the city’s credit card processor had not received any reports of compromise and a completely rebuilt and certified payment portal went back online for public use Monday. City officials say a preliminary forensic analysis on the server showed no evidence of credit card skimming malware.