Kirinyaga: The Mwea Irrigation Scheme in Kirinyaga County continues to stand out as one of Kenya's most impactful agricultural investments, driving billions of shillings into the economy and transforming the livelihoods of thousands of households. Established in 1954, the scheme has grown into the country's largest rice producer and a major source of income, employment, and economic activity for the region. Stretching across 31,271 acres of irrigated land and supporting more than 15,900 farmers, Mwea is the backbone of Kenya's rice value chain.
According to Kenya News Agency, the scheme draws its water from Rivers Nyamindi and Thiba, enabling the cultivation of rice and several high-value horticultural crops. Thanks to improved water supply and expanded acreage, annual rice production has surged from 98,400 metric tonnes to more than 160,000 metric tonnes. A presentation made to Cabinet Secretary for Water, Sanitation and Irrigation, Eric Mugaa, during his tour of the scheme highlighted Mwea as a key national food security asset and a major contributor to local industry.
The scheme acts as a lifeline for over 100 rice millers operating within the Mwea cluster, supplying vital raw materials for processing, packaging, and distribution both locally and across the country. Its expansive value chain is now estimated at Sh25 billion annually, with farmers earning Sh12.7 billion directly from rice production. A significant boost came with the construction of the 15.6 million cubic metre Thiba Dam, which has stabilised water flow throughout the year. The reliable water supply has made it possible to implement three cropping programmes: main crop, ratoon crop, and double cropping, greatly increasing productivity.
The dam also expanded the irrigated area from 25,461 to 31,271 acres, giving more farmers the ability to plant and harvest consistently. Government subsidies have further eased production costs for farmers. Inputs such as TSP and top-dressing fertiliser are availed at far below the market price, allowing growers to maximise profits while maintaining high yields. This support has strengthened the livelihoods of thousands of families who rely on rice farming as their primary source of income.
Socially, the scheme has become a major employer, offering jobs to youth and women in farming, milling, transportation, and trade. Its vibrant rice economy has stimulated business growth in markets, agrovet shops, transport services, and retail enterprises, creating a ripple effect throughout Kirinyaga County and beyond. Mwea has also enhanced food security for households and contributed to a stable rice supply across the country.
Despite these gains, the scheme is grappling with the spread of the destructive Golden Apple Snail, deterioration of on-farm canals and roads, vandalism of water control gates, and limited funds for infrastructure maintenance. However, stakeholders, including the National Irrigation Authority, farmers' cooperatives, and the county government, are enhancing collaboration to strengthen management and sustainability. Capacity-building initiatives targeting farmers, the Irrigation Water Users Association, and dispute resolution committees aim to improve efficiency and promote responsible water use.
CS Mugaa noted that as the government continues to invest in irrigation-driven agriculture, Mwea stands as a model of how strategic infrastructure, farmer participation, and government support can unlock economic potential. With its ever-expanding production capacity and strong social impact, the scheme remains a cornerstone of the country's agricultural development and a lifeline for thousands of Kenyan families.
The CS, accompanied by senior officials from the National Irrigation Authority, the county government of Kirinyaga, and other stakeholders, assessed the progress of the expansion of irrigation canals, rehabilitation of drainage systems, and improvement of on-farm roads within the scheme. These upgrades are expected to boost efficiency in water delivery, ease farmers' access to their farms, and support increased rice production.
During the visit, Mugaa also engaged with rice farmers and officials, listening to their concerns and sharing updates on the government's commitment to modernising irrigation infrastructure across the country. He reaffirmed the Ministry's dedication to supporting farmers to increase yields, strengthen food security, and expand economic opportunities within the region. The Mwea Irrigation Scheme remains Kenya's largest rice-growing zone, and the ongoing improvements are part of wider national efforts to enhance irrigation systems and promote sustainable agricultural development.
Kirinyaga Deputy Governor David Githanda has urged contractors undertaking county development projects to strictly adhere to agreed timelines and quality standards. He assured that the county government would continue collaborating closely with the national government to improve irrigation infrastructure and strengthen support for farmers across the region. He noted that upgraded irrigation systems are essential to boosting agricultural productivity, particularly for rice farmers who depend heavily on a reliable water supply.
Meanwhile, Mwea Member of Parliament Mary Maingi reaffirmed the government's commitment to protecting local rice farmers amid concern over the status of the Mwea Rice Mill. Maingi dismissed claims that the facility was at risk of being auctioned, stressing that the mill remains the property of farmers. She assured growers that the government will continue to prioritise the purchase of local rice before approving any importation, a move aimed at shielding farmers from unfair competition and stabilising market prices. Both leaders emphasised that strengthening agricultural value chains remains a top priority as the region works to enhance food security and improve farmers' livelihoods.