by Rod Hughes
It seems like a “no brainer,” but La Nacion reports today that the flooding metropolitan areas suffered this week is due to antiquated, inadequate storm sewers, exacerbated by a build up of litter and garbage. In San Jose a squad of 30 workers constantly tries to maintain the sewers, to prevent the entry points from being clogged.
Costa Ricans are, unfortunately, notorious for tossing litter casually into the street and others cannot be bothered to wait for the day of the weekly garbage pickup but place their refuse on the curb where it washes into the sewer system. The San Jose squad, for example, collects 20 tons of garbage per week.
But the sheer volume of water that fell Monday, 70 liters per square meter in Tibas and Alajuela in only three hours, when the average rainstorm dumps only 10 or 20 liters was bound to have its effect.
But worse, even without the garbage, the standard 24-inch storm sewers are inadequate to handle a really hard cloudburst. These pipes should be from 36 to 50 inches, says Roy Delgado, director of urban development in Alajuela. Some of these concrete pipes actually ruptured under the pressure, he added.
Hidden beneath the city streets both in Tibas and Alajuela, the country’s second-largest city, is an amazing disorder, experts say. Delgado noted that each builder seems to have his own idea when new structures go up because of a lack of standards and supervision.
Nowhere is this chaos more obvious than in Tibas where an engineer has ordered adequate drainage but that runs into a storm pipe installed by the city in days past when no one seemed to plan ahead. Thus, a new neighborhood’s 50-inch pipe runs into a 14-inch with the predictable result of backup of water and flooding.
Even at that the country was spared the effects of Hurricane Dean that devastated Jamaica a couple of weeks ago. It passed far enough offshore not to cause torrential rains. It was represented only by heavy wave action in the Limon area, causing now damage.
Elsewhere in the country, one man was swept away and drowned in a flashflood while another barely escaped with his life.