NKHOTA-KOTA, Malawi, August 28, 2021 (AEJ) - In Mchinji forest close to Ndawambe and Sitolo villages in Traditional Authority Mlonyeni rises mighty Bua River from below the ground. It meanders through four districts namely; Lilongwe, Kasungu, Dowa, Ntchisi and finally Nkhota - Kota. This is the only river that runs overs 250 kilometers entering a protected area before it empties its waters into Lake Malawi.
Bua River has for centuries presented the highest potential to thousands of people along its path with livelihoods in terms of support to agriculture, eco-tourism and fishing. But recent findings of catchment degradation at its source threatens the sustainability of the various ecosystem services to populations downstream.
This threat at its source ranges from catchment encroachment to large-scale irrigation using treadle pumps in a water-logged area. This is further exacerbated by effects of climate change explains acting Environmental District Officer for Mchinji Chrispine Soko in an interview.
Soko’s remarks are echoed by Fortune Mwafulirwa, the District Forestry Officer who laments about careless cutting of trees leading to large-scale production of charcoal.
“As an extension, other challenges include, inadequate partners to take part in ecosystem restoration activities. We are also hoping, that government will consider increasing allocation of funding for law enforcement,” Mwafulirwa explains in an interview.
Fluctuating water level downstream
In Nkhota-Kota, the final leg before Bua River enters Lake Malawi, a weir was constructed in 2005 for irrigation purposes. However, water levels have been fluctuating over the years and people had a rude awakening when the river completely dried up in 2014, according to irrigation records at the district.
As a multi-purpose structure, the weir was designed with fish ladders to allow Lake Salmom Mpasa move up and down stream during spawning period. Mpasa an endemic species ascends Bua River from Lake Malawi during March to July. It requires clean gravel surfaces for spawning grounds and this is available within Nkhota-Kota Wildlife Reserve.
As such interests on irrigation, water levels, fishery and the environment necessitated a need for technical experts to touch base with the USAID funded Restoring Fisheries for Sustainable Livelihoods in Lake Malawi program to explore practical solutions to achieve all these needs holistically.
According to Charles Mandala, Acting District Fisheries Officer for Nkhota-Kota improving the current ladder on the weir or constructing a new one could enable Mpasa and Sanjika to complete their migratory cycle between spawning grounds and the Lake Malawi.
“Adult move upstream and young fish could swim easily downstream unimpeded. This could solve the problem of diverting juviniles to the rice scheme from the main river and contribute fish biodiversity increase,” says Mandala after the stakeholders meeting.
Vincent Sitima Phiri, Senior Irrigation Engineer and District Irrigation Officer explained that purpose of the weir is to divert water to Bua Irrigation scheme which has the potential of 365 hectares of agriculture land for cultivation supporting 900 farming households.
The fish ladders were constructed in 2005, they now need modifications as they are in two categories. There is fish ladder that was constructed to aid adult Mpasa upstream migration to swim over the weir, which has blocked the route. In the dry season, the weir obstructs young fish, which are migrating to the lake where they grow into adults.
The peak migration of young Mpasa occurs in August, which happens to be the height for water demand for the irrigation scheme. As a result of this blockage, most young fish who would have gone to the lake to grow and contribute to fish diversity end up in the irrigation scheme.
As experts, Phiri added we are discussing a solution to enable the juveniles to navigate the ladder and swim downstream to the lake instead of going into the irrigation canal where they eventually die. This was also considered in 2005 because there is an opening channel where we are supposed to install the sluice gates. So, with the passage of time may be the gates were stolen or washed away.
“However, during our site visit today we were supposed to have a synergy on how this can be done collectively. At the site you can witnessed they are so many sectors that are involved. There is a data house for water department, environment, fisheries, irrigation, agriculture, forest and wildlife. All these have to be involved in what we are doing. The intervention must be a collaboration with other stakeholders to avoid re-inventing the wheel to consider both minimum and maximum flow of the river,” said Phiri after the event.
Daniel Jamu, Deputy Chief of Party of USAID funded REFRESH project said it is important that all stakeholders are engaged because the water resource is used for multiple purposes.
He added that there is a need for a win-win situation without negatively influencing irrigation activities. So, we must come up with a solution and guidelines for regulating the water, which are acceptable by all stakeholders. Abraham Malijani who is Traditional Authority Mphonde agrees on a need for different technical experts to be present to ensure that whatever design is made on the weir caters both irrigation and sustainability of Mpasa species.
The coordinated activities at addressing Bua weir are in line with the Malawi National Green Climate Conference that took place on the 26th and 27th of August in Lilongwe the capital.
The green conference was held under the theme: Collective Responsibility for Enhanced Climate Action in Malawi. The conference aimed at exploring ways of advancing coordinated efforts among different players aimed at mitigating and addressing the impact of climate change ahead of the UN Conference of Parties to be held in Scotland later this year.