A drainage project in downtown Monterrey has created a sustainable blueprint for rainwater reuse
Monterrey is the capital of Nuevo Leon state in the north east of Mexico. With a population of 4 million it is the third biggest city in Mexico. In the arid northern regions of the country, water scarcity is becoming an increasing problem caused by over-extraction from underground aquifers.
In a social rehabilitation project, 1.5 hectares (3.7 acres) of abandoned street islands running along eight blocks of Monterrey’s main Edison Avenue close to the city center have been transformed into a meeting point for the local community.
With a catchment basin of 540,000 sq meters (133 acres) draining almost 300,000 cu meters (10,500,000 cu ft) of rainwater, the area was prone to heavy flooding and subject to pollution from trash and other floatable debris as well as from hydrocarbons carried in the runoff during storm periods.
A solution designed and built by Solutions Hidropluviales of Mexico City used storm water treatment technologies from Hydro Intl. in combination with storm water storage to recycle rainwater, irrigate the islands and plant a green corridor of 170 oak trees.
The project uses Hydro vortex separation technologies to clean runoff upstream of two retention tanks, explained Alberto Burgoa, president and CEO of Solutions Hidropluviales, who are Hydro’s storm water product distributors in Mexico.
“Using rainwater retention for storm water management has not been common in Mexico, but we believe it could have great potential as a sustainable solution that can help combat the country’s severe water scarcity problems,” Burgoa said. “The solution we have engineered will store enough water to irrigate the oak trees for 62 days. We hope the technology we developed can not only provide clean water for irrigation projects, but also be used for industrial or other urban regeneration schemes throughout Mexico.”
The new rainwater harvesting solution  was retrofitted underneath one of the traffic islands with treatment solutions supplied via Hydro’s U.S. Stormwater Div., headquartered in Portland, Maine.
A Hydro Downstream Defender vortex separator removes sediment, oils and floatables from the stormwater before it enters the first 186 cu meter (6,569 cu ft) plastic tank designed to regulate the flow and store water. At the outlet to the tank a Hydro Up-Flo filter provides further storm water filtration to remove fine sediments nutrients and metals. Finally the water passes into a 62 cu meter (2,190 cu ft) storage tank, from where it is pumped to the drip irrigation system.
“We completed the drainage project in a very short three-month timescale. The Hydro products were quick and simple to install,” Burgoa said. “The Downstream Defender and Up-Flo filter will require maintenance twice a year, which is minimal compared to alternative storm water treatment solutions.”
The regeneration of the Edison district is being led by OXXO, the national convenience store chain which has its headquarters in the area. OXXO gathered a group of investors and sponsors to form The Trust Poligono Edison, which includes the FEMSA bottling corporation, Monterrey Municipality, Monterrey Football Club and the U.S. Consulate.