As the 29th Brigade advanced toward the Mivo River , torrential rain and flooding ultimately brought the advance to a halt . The height of the river rose 2 metres ( 6 @.@ 6 ft ) . The Buin Road was reduced , in the words of Gavin Long , " to a sea of mud " and many of the bridges upon which the Australian supply system was dependent were washed away . This rendered large @-@ scale offensive infantry operations impossible and as the situation worsened for a period of time the Australians even ceased patrolling operations across the Mivo ; meanwhile , the Japanese continued to harass the Australians , probing their positions and setting mines and traps , targeting the Australian line of communications . On 9 July , the 15th Infantry Battalion fought off a series of attacks around Siskatekori , at the junction of the Mivo River and the Buin Road , which included a heavy Japanese artillery bombardment . Australian patrols were resumed in late July and continued into August . These attacks proved very costly , particularly amongst the Australian engineers that were tasked with rebuilding the bridges and roads that had been destroyed in the flooding .