BAGAMOYO, Tanzania
A public school in Tanzania is implementing an innovative rainwater harvesting project, which has helped curb the wave of waterborne disease caused by saline intrusion and affected the health and academic performances of students.
Ground aquifers, a major source of water in the drought-hit Bagamoyo district are facing an emerging threat from saline intrusion, which has reduced its natural ability to replenish dissolving salts.
The saltwater, pushed inland by sea waves from the Indian Ocean, is damaging groundwater tables in Bagamoyo while tainting freshwater sources.
Acute drought
Saline intrusion, which scientists have linked to climate change, involves the movement of salty seawater into freshwater aquifers. As the sea level rises, it floods low-lying wetlands and increases the salinity of rivers and groundwater tables, according to local experts.
The acute drought experienced in Bagamoyo and the rising sea level have forced saltwater to seep into ground aquifers that hold freshwater — making it too salty.
To cope with the challenge, the Kingani Secondary school uses a rainwater harvesting technique to catch water during the rainy season and use it in the dry season when groundwater becomes unbearably salty.
Dickson Watson, a water and environmental engineer at Wema Consult, a local engineering firm contracted to build the system, said the rainwater harvesting system has allowed the school to collect enough water to get through the dry season.
“We harvest rainwater from the corrugated rooftops and store it in the reservoirs which students use in the dry season,” he told Anadolu Agency.
According to Watson, the company has constructed and installed several concrete and plastic tanks with the capacity to store 147,000 liters (39,000 gallons).
Although ground aquifers play a huge role in supplying freshwater for domestic use, irrigation, and supporting diverse ecosystems, they are increasingly threatened by the increasing salinity.
Bouts of diseases
At the school, students who suffered headaches, stomach aches, diarrhea, and ulcers after guzzling salty water, are ever thankful for to the project as the UN COP26 climate change summit begins in Scotland.
Lucy Michael was in class when she felt a stabbing pain across her stomach which provoked an irresistible urge to vomit.
“I felt dizzy and confused,” she told Anadolu Agency.
She rushed to the bathroom, sat in a squatting position with her head resting on her palm, and vomited until she was empty.
The 16-year-old was diagnosed with typhoid fever and chronic stomach ulcers, which doctors attribute to guzzling salty water.
“I didn’t have the money to buy bottled water, so I ended up drinking the available water, I was wrong,” she said.
Jason Raphael, a water engineer at the Bagamoyo District council said when freshwater is tainted by dissolving salts, it becomes potentially dangerous for human consumption.
“Salty water is dangerous because it contains high concentrations of dissolved solids and inorganic matters,” he told Anadolu Agency.
The rainwater project, which was supported by the UN Environmental Program (UNEP) has resolved the students’ predicament as the school collects more than enough water.
“We get enough water. Some of it is boiled and used for drinking, and others for washing and other uses,” Lucy said.
Sylolian Stephen, the deputy headteacher at the school said the salt intrusion was a serious problem that badly affected students’ performances.
“We have had many cases of students who fell sick after drinking salty water, some of them experienced dizziness, fatigue, and severe dehydration, which had affected their class performances,” Stephen told Anadolu Agency.
Students had been spending more time looking for water instead of studying in class, he said.
“In the dry season, water becomes too salty, you cannot even use it for laundry. We use rainwater instead,” said Lucy.
Reduced costs
The system has also helped the school to offset costs it incurred paying for water to be trucked in and reduce the inconvenience to students.
“We have increased our water security and the students no longer waste time fetching water,” Lucy said.
The stored rainwater is useful in dry the season when the region experiences acute water shortage, added Stephen. “The students have learned to be more alert and conscious to preserve water,” he said.
The harvesting project, which involves rooftop guttering and a maze of large tanks that students can use for laundry, cooking even drinking, seems to have resolved the water problems.
Gladness Richard, a form four student who suffered typhoid fever in 2018 after drinking contaminated water is happy the rainwater system has resolved the problems.
