Mérida, Yucatan (October 19, 2020).- Construction rules in Merida’s north, where developers have been building malls and housing developments in the past several decades, will have to be re-written to address the realities of a shallow water table and inevitable climate change, experts said.
Record rainfall has left newer housing developments flooded and anything built underground — like underpasses and parking garages, fared terribly. The floods also expose the city’s historically poor urban planning, which focused on sites closer to the beach and with less capacity to absorb water.
“Flooding has been rampant,” wrote blogger William Lawson. “The newer neighborhoods of Las Americas and Caucel seemed especially hard hit. Entire streets were converted into lakes and rivers. Homeowners, desperate to see the water disappear, took the unfortunate and ill-advised step of removing the grates from the drains, thereby exposing the wells to garbage, leaves and more. The wells were, in fact, not absorbing water; rather, they were acting as springs, spewing up groundwater into the streets around them.”
The Merida City Council formed a committee to deal with the serious floods that remain a week after Hurricane Delta brushed by Yucatan.
Hydrolic specialists Jorge López González, Juan Vázquez Montalvo and Ismael Sánchez y Pinto joined municipal officials in drafting new rules and regulations.
“Today global warming is an issue that has to concern us,” said Mayor Renán Barrera Concha. “Not only will we have to make a change in construction regulations, but also in the Municipality’s Urban Development Program and in the human settlements law.”
Also, he said, there will be changes in the real estate development law, which will have to be done by the state government because Merida’s regulations are congruent with what the state-level legislators approve.
An example would be to limit underground parking garages to one level, said López González. Additional parking levels would be above ground.
Sánchez y Pinto explained that Merida’s subsoil is uneven in its capacity to absorb rainwater.
“The wells in the Centro may have a high absorption capacity, but that does not mean that all of Merida has that absorption capacity, it is something that varies,” he said.
“We are at the moment of learning and solving; we have to review what it was that in these areas has caused these floods to occur. Rather than looking for the culprit, we must seek to understand the physical problem, review, do a study and understand what are the crucial factors that we must take care of and how we can act to solve the problem,” he said.
At least three major rain events have challenged Yucatan’s flat, low-lying peninsula. June brought Tropical Storm Cristobal, which beat 2002’s Hurricane Isidoro in rainfall. In just five days, 600 mm / 24 inches of water fell from the sky.
Just over 100 days later, Storm Gamma and Hurricane Delta arrived in rapid sequence, dumping another 1,217.5 mm / 48 inches of rain.