When are Quarterly Estimated Taxes Due? Estimated taxes are due quarterly on specific dates during the year. The IRS mandates that the normal due dates for estimated taxes are April 15 for the first quarter of a year, June 15 for the second quarter, Sept. 15 for the third quarter and Jan.15 of the following year for the fourth quarter.
Salt water intrusion occurs in coastal freshwater aquifers when the different densities of both the saltwater and freshwater allow the ocean water to intrude into the freshwater aquifer.hen this occurs, it will move the saltwater freshwater interface inland, resulting in a higher saline concentration in the aquifers' water, rendering it useless for human consumption, unless it is treated. Figure 4. Saltwater Intrusion Situation(University of Florida, 2000)).
Storm surge is one of the main causes of coastal inundation. Storm surge is the abnormal rise in water level, over and above the regular astronomical tide, caused by a severe storm such as a tropical cyclone or nor'easter.arge waves also raise coastal water levels and ride on top of the storm surge to cause extreme damage. Coastal inundation is the flooding of normally dry, low-lying coastal land, primarily caused by severe weather events along the coasts, estuaries, and adjoining rivers.