The population centers along the coast is locked between the Atlantic Ocean (north) and a series of storage reservoirs (conservancies) to the south.
The "highest rainfall totals on the order of 20 inches of rain (red areas) occur just offshore and right along the coastline of Guyana near the mouth of the Essequibo River and Georgetown".
[4] Between December 24, 2004, and January 20, 2005, three distinct rainfall episodes occurred, which resulted in some coastal areas of Guyana receiving over 100 cm (39 in) of rain.
The water conservancy was overloaded, and local drainage systems were inadequate to bear any additional burden.
After January 19, there was lull in rainfall, which allowed a significant amount of water to drain off higher grounds but many areas were still flooded.
Kokers were jammed and inoperable, resulting in floodwaters, which by this time had overwhelmed drinking and wastewater management systems, being unable to escape.
[8] Rains continued until the first week of February 2005, but floodwaters receded slowly and damage to low lying infrastructure, agriculture production and livelihood were beginning to show.
[3] The heavy rain left two-thirds of Guyana's capital, Georgetown, flooded, affecting over 120,000 and killing six.