Economically, equipment and material costs are high. These initial costs of RWH systems are prohibitive for most individual households. On top of these, low quality workmanship partly contribute to an immature market for rainwater business.

Socially, due to poor water quantity and quality as well as lack of successful demonstration projects, RWH is not highly prioritized as an alternative water supply source. Despite the demonstrations constructed within communities, there are no customized policies or regulations enforcing the adoption nor incentives. There is limited awareness of RWH best management practices. Free donations without any kind of reciprocation from beneficiaries results in reduced commitment to management of the provided system. Moreover, local water committees have accessibility challenges to financial and technical support due to limited recognition within government bodies.

For improvement of RWH practices in the country, 19 solutions have been proposed to address the common problems raised above (Figure 3). With specific guidelines, standards, and regulations in place, the targeted technology potential can be achieved and adoption can be increased. Follow up on implementation of currently passed RWH bylaws as per mandate given to local government authorities (LGAs) is needed. In addition, the remaining LGAs should be encouraged to pass their bylaws. As of May 2015 only 29 out of 168 LGAs had such bylaws in place.

Media involvement, training, and inclusion of technology basics in the education system can serve to boost technology awareness as well as empowerment. Social and financial strategies can allow users to afford their own systems with reduced reliance on donors, and thereby boost their sense of ownership, guaranteeing a system that is operated and maintained well. Government financial support to interested individuals and communities is of paramount importance. This can be through incentives and provision of subsidies.

The Tanzanian National Water Sector Strategy [17] acknowledges that RWH can play a role in offsetting water shortages. However, current promotional efforts through demonstration projects are not enough. There is much to learn from other countries including Germany, Japan, Korea, Australia, with respect to the adoption and promotion of RWH technology, for which attempts including knowledge dissemination, provision of subsidies and incentives, as well as exemption in taxes for RWH facilities have been made. As a way forward for Tanzania, a strategic plan is needed to address issues that

have been affecting sustainability of water supply projects namely; ownership, maintenance, cost implication, enforcement, research and development, empowerment, and awareness [18] .

Specific regulations are imperative for guiding, restricting, and enforcing the adoption and attainment of the targeted technology potential. These should be recognizable at national level. Furthermore, national RWH technology guidelines and standards are vital. Fortunately, the Water Resources Management Act No. 11 of 2009, on page 366, gives citizens the right to establish personal RWH system for domestic purposes within their premises.

Establishment of enabling policies and cost-sharing strategies, including the provision of subsides along with technical know-how and capacity building for promotion of RWH is recommended [19] . To promote urban water harvesting, policies should include a mix of incentives and penalties, and that such policy initiatives should be strengthened further through legislation [20] .

Existence of a research center would help play the role of exploring, studying, and sustaining a technology. For development and sustainability of a RWH technology, engaging in respective research is essential. For years, a number of agricultural research centers have been active in the country, unlike water-specific ones. As a way forward, to sustain, develop, and address prevailing water supply challenges, it seems imperative to propose the establishment of a water research center as a stand-alone entity, because water is equally important for one’s life and welfare. Indigenous knowledge on rainwater harvesting has been in existence since memorial, such knowledge needs to be evaluated and thereafter improved in a sustainable manner.

The center can be affiliated with government sector, universities and colleges, industrial and private sectors, and individuals, for increased efficiency and influence.

For sustaining the application of the technology it is equally important to empower people financially rather than only technically e.g., educate on self-funding and self- supply initiatives. Therefore, the role of beneficiaries should be increased through various strategies in order to overcome the challenge posed by the cost of RWH construction, and also to dispel the free water attitude and instill a sense of ownership. This would ensure project sustainability in the long run. For instance, in Korea, the Seoul Metropolitan Government passed a regulation that facilitates joint financial contribution from local government, the Donor Company, and volunteers for implementing RWH projects [21] .

A self-supply initiative is a low cost approach to service delivery, initiated by individual families or groups. This initiative was facilitated while promoting RWH in rural areas of Thailand [22] . Self-supply initiatives can serve as a motivator to external support from the government and the private sector as well, upon seeing internal efforts to improve the standard of living. Moreover, it reduces the reliance on government support. Systems financed under self-supply initiatives have the potential for better maintenance and management. These may include, co-financing, cash/in-kind contributions, labor contributions, and microfinancing.

In community RWH projects, the involvement and cooperation of the public sector, the community and the private sector is essential. Each entity involvement has a beneficial impact on the project implementation and sustainability. Companies with suitable policies on community outreach activities can perform a 1C1C campaign as a CSR activity and gain recognition by the community and the public. This would cause the effective dissemination of technology, and address financial constraints.

With the advancement in technology, the processes of implementing demonstration projects so as to promote specific technologies are imperative. However, appropriate strategies are required to ensure their acceptability is instilled in communities and facilitate change of individual mindset as they acquire spirit of project ownership within their knowledge and financial comfort zone. A demonstration project should serve as a model for promotional plans, to guide, train, build capacity, and ensure consistency in design and application of the technology. During demonstration, training and capacity building should be provided to engineers, technicians as well as beneficiaries. Construction and maintenance empowerment should be targeted, and adoption and aware- ness promotion aimed at. Post project evaluation is essential. Moreover, water problems are site specific, it is therefore advised that location for pilot projects should be representative of areas with specific unique rainfall characteristics, topographical and geological conditions [16] . For the case of a country like Tanzania, this includes unimodal and bimodal regimes, mountainous and arid areas. Hence, the targeted technology potential can be achieved.

Clearly stipulated government roles are essential in ensuring implementation of given advocated technology in community. Countries such as Australia, Germany, India, Japan, in support of RWH practices by individuals and communities, their offering incentives, subsidies, tax exemptions, rebates, and in some countries these are strengthened through legislations [23] [24] . Tanzania government should invest in offering incentives and subsidies to support individual efforts to address their water supply challenges with RWH. In recent years in an effort to boost agricultural production and the livelihood of rural households, the government has been offering farmers subsidies on seeds and fertilizers [25] [26] . Further, the Tanzania Social Action Fund (TASAF) is implementing a productive social safety net, whose subcomponent is conditional cash transfer that targets poor and vulnerable families [27] . The conditions imposed are those of health and education compliance. Similar efforts are proposed towards promoting RWH. Alternatively, RWH can be incorporated as a condition in the TASAF program. People can be advised to use some of the funds provided to install a simple RWH facility for meeting the drinking and cooking demands of the family. A favorable deal/tender can be secured with an engineering company/industry to produce cost effective storage tanks for such a project with TASAF. This would ensure that health is not jeopardized, thereby also impacting education through increased school attendance. Further, with healthy bodies and a relaxed mind, more energy can be invested in economic activities, including agriculture which employs more than 80% of the population.

Mnyundo primary school RWH demonstration project in Tanzania has displayed potential for sustainable community RWH projects, with simple techniques improving on quantity and quality, community involvement in operation and maintenance, and system affordability. This demonstration project serves as a display of how current RWH practice problems can be addressed. Moreover, 19 solutions have been suggested to address identified problems of current RWH practices in Tanzania. These include, having RWH manuals, guidelines and regulations and promoting self-financing initiatives. Hence, with RWH technology community members can address their water supply challenges, water service coverage can be increased, and direct dependence on government finances reduced.

Furthermore, authors recommend on an action plan with the following strategies for improvement in RWH adoption and sustainability in the country:

・ Investment in RWH promotion by government, and provision of incentives and subsidies.

The various strategies on RWH technology described in the study can be easily adopted and implemented in other regions with similar climatic condition and policies.

This research was supported by Korea Ministry of Environment as Eco-Innovation Project (413-111-008). The authors also acknowledge the partial financial support of KSCE and IRICEE for the demonstration project, and the involvement of the Mtwara District Office in Tanzania.

Cite this paper
Mwamila, T. , Han, M. and Katambara, Z. (2016) Strategy to Overcome Barriers of Rainwater Harvesting, Case Study Tanzania. Journal of Geoscience and Environment Protection, 4, 13-23. doi: 10.4236/gep.2016.49002.

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