Complex sentence: There is a larger base plank at the start of the bridge where the Zayandeh River flows under it, supporting a tea house which nowadays is abandoned due to the shortage of water and the river drought due to government mismanagement.
Split into simpler sentences: There is a larger base plank at the start of the bridge where the Zayandeh River flows under it. This supports a tea house which nowadays is abandoned due to drought which some claim is due to government mismanagement.