Improving Irrigation Systems: Plastic Bottle Drip Irrigation Phase One

THE PROBLEM

Farmers in Flores have difficulty growing enough food for their daily minimum needs during the eight-month dry season. The majority of households in Flores depend on subsistence farming. Maize is their main food staple, and more than 60 percent of families grow maize and cassava for their own consumption. 

However, it is difficult for farmers to grow sufficient crops during the long dry season due to water shortages and a lack of functional irrigation systems. Although 24 percent of farmers have access to some kind of irrigation system, these do not help during the dry season because it is difficult to store water. Furthermore, the dry, rocky soil in many areas absorbs water quickly. When there is no rain, farmers must water their crops every day, which is impossible when rainwater cannot be stored from the wet season and well water is brackish. Instead, the farmers must rely on stored or purchased produce to fulfill their minimum daily needs. A better irrigation system is needed to alleviate hunger under drought conditions.

THE SOLUTION

Kopernik will work with farmers in Kotauneng village in East Flores to test a system of drip irrigation using plastic bottles. This simple, accessible system needs 75 percent less water to grow maize. We will test the system with well water and three different crops. One crop will be selected for each of the following criteria: 

• one crop which is familiar to the farmers and which they are used to consuming (in this case, this will likely be maize); 
  
• one crop suited to the rocky, sandy soil; 
  
• one drought-resistant crop. 
  

We will use 10 plastic bottle drip irrigation systems for each crop, or 30 in total. During a four-month period in the dry season, we will record the progress of the crops grown using the plastic bottle drip irrigation systems. The indicators we will measure are: 

• the survival rate of the plants; 
  
• their yield;
  
• the volume of water used for irrigation. 
  

We will also calculate the average cost of production using the plastic bottle drip irrigation systems to see if it is a viable product for low-resource farmers.

THE EXPECTED IMPACT

We hypothesize that the plastic bottle drip irrigation system will allow farmers to produce food in drought conditions where they were previously unable to.

THE PROJECT RESULT

Based on these results, we proved that the plastic bottle drip irrigation system enabled farmers to grow peanuts during the dry season where normally they did not grow anything at all. The drip method recorded a lower plant survival rate and yield than the manual method, with 90 percent survival rate and an average yield of 18g per plant, by using 63 percent less water for irrigation. This result indicated that the drip rate applied was too low and could be increased (with the total volume of water still kept lower than the manual method) to produce an equal yield with the manual method and still use less water.

While we could grow peanuts with our drip irrigation technology, we were not successful in doing so with corn, chilies or sorghum. For these three plants however, given they died with both the manual method and the plastic bottle drip irrigation method, it is likely that the drip irrigation mechanism was not the main issue, rather it was more likely that the fertility of the land or that the amount of water provided during the late vegetative stage (for corn) was insufficient.

Regarding the cost analysis, we also found that the cost from growing crops using the plastic bottle drip irrigation technique was 21 times more expensive for buying the same amount of peanuts from the market. Even with a higher yield per plant such as corn where the cost of the technology is minimal, it is still more expensive to grow the crops. than to buy the same amount of produce from the market, rendering this solution unviable in this scenario.