Landscape architecture in Kenya is one of the relatively new sectors of the already complex construction industry in sub-Saharan countries. The practice is currently unregulated compared with the existing AEC practices in the country, leaving room for creating poor-quality landscape projects due to lack of adherence to the set global standards of practice for the profession, thus compromising sustainability standards in landscape architecture. Landscape architecture is essential in shaping the environment by prioritizing resilient and ecologically sensitive construction. It is the leading practice of sustainable construction practices globally, mitigating the negative impacts of construction, such as storm water runoff, air filtration, phytoremediation, microclimate control, the use of sustainable materials, advocacy, and sustainable site design. However, the practice faces significant challenges that impede the realization of a holistic, sustainable construction approach, especially for megaprojects that affect the public. This study was necessitated by the public uproar that occurred due to the derelict landscape spaces created during and after the completion of megaprojects in the country, such as the Nairobi Expressway and the Standard gauge railway projects, which posed significant ecological concerns. According to ^[1], emphasis on environmental sustainability is crucial in the overall achievement of sustainable development goals, especially in developing countries where the concept of sustainability is yet to be fully assimilated into construction processes.

According to ^[2], “sustainable landscape management is a philosophical approach to creating and maintaining landscapes that are ecologically stable and require less inputs”. Sustainable construction practices in landscape architecture and engineering projects therefore encompass the social, economic, and environmental tiers of a society. Sustainable practices should commence from landscape design to the construction, maintenance, and post occupancy stages of a project by incorporating the use of sustainable practices, technology, materials, and processes, as stipulated in sustainable development principles. The authors in ^[1] state that emphasis on environmental sustainability is crucial in the overall achievement of sustainable development goals, especially in developing countries, where the concept of sustainability is yet to be fully assimilated into their construction processes. Further research in the field has indicated that there has been a bias toward research on operational phases, neglecting other important phases from design to deconstruction, which also need further emphasis to achieve a holistic approach toward sustainable construction and environmentally sustainable construction (ESC). This has led to gaps in the holistic approach to monitoring and evaluating sustainability. There are several sustainability theories that have previously been developed in order to aid in the understanding, implementation, and evaluation of SC globally. These theories include corporate social responsibility (CSR), corporate sustainability (CS), stakeholder theory, institutional theory, resilience theory, ecological modernization theory, and green economics. CSR and CS are interchangeable theories that state the obligation of companies to implement sustainable practices even in instances where there are no legal requirements. However, according to [3,4]^[3][4] there is still room for further improvement in the existing CSR model to improve the practical, legal, and institutional frameworks to mandate all contractors to adopt these strategies. According to ^[5], stakeholder theory argues that stakeholder cooperation follows a specific purpose. The complexity of sustainable construction often leads to reluctance to accept sustainability proposals; therefore, they influence the uptake and evaluation of sustainability in their projects. All of these theories collectively dissect the compliance and complacency of the uptake and evaluation of the effectiveness of sustainable construction practices locally and globally. Holistic sustainable construction practices include sustainability literacy, sustainable procurement practices, sustainability compliance, and sustainability assessment frameworks. According to ^[6], sustainability literacy entails understanding the need for change towards sustainable practices, sufficient knowledge by practitioners to favor sustainable development, and the ability to recognize and reward people’s positive actions towards upholding sustainable practices. Sustainable procurement evaluates the value for money in sustainable construction and is key to the improvement and monitoring of trends within the construction industry. In Kenya, sustainable procurement practices have recently been adopted such as ensuring green inventory management, green specifications, and green tendering processes by encouraging suppliers and contractors to incorporate sustainable or recycled products to attain good value for money. However, the acceptance of sustainable construction is still lagging due to other challenges faced in the construction industry that directly affect the procurement processes ^[7].

2. Sustainability Compliance Globally and in Kenya

The level of compliance with sustainability practices varies from one continent to another as well as within different countries in the same regions due to various reasons. The compliance with and uptake of sustainable practices is generally high in countries in the European, American, and Asian continents in comparison to Africa. The driving factors influencing high levels of sustainability include the existence of mandatory construction regulations, legislations, and drivers that positively influence the growth and adoption of green building. Despite the existence of initiatives promoting these practices, there are still some challenges facing the quality management and implementation of sustainable and green construction due to reluctance, partial compliance, and misunderstandings due to unfamiliarity with sustainable practices ^[8]. Most of the compliance tools used in the rating of sustainability, such as the LEED, BREAM, EDGE, and Greenstar rating systems, were devised in developed countries. One exception is the Safari Green building index tool, which was developed in Kenya, with the aim of localizing the criteria for rating the efficiency of sustainability in the projects within the country. These tools have different rating standards specific to each one. Notable differences in compliance with sustainable construction across different countries are related to the regulations and policy implementations in each country. Kenya has previously relied on the use of three different rating systems; therefore, the creation of a local tool will increase the acceptance of sustainability accreditation ratings with the aim of improving awareness within the country. Compliance with sustainable construction principles is spearheaded by government legislations and restrictions and has been significantly low, but it has shown significant growth over the last five years. According to ^[9], there is a significant lack of sustainable construction strategy in Kenya and “the Kenyan government is yet to make sustainability a core subject in the construction industry operations”. The legal framework in Kenya does not have sustainability as one of its facets, thus leaving the uptake and monitoring of sustainable practices in this highly fragmented industry entirely voluntary.

3. Sustainability Assessment Framework and Project Management

Globally, there are different sustainable building assessment methods with various strengths and weaknesses due to the influence of the scope of work, different requirements, and the different categorization of elements. These tools include material flow analysis, cost–benefit analysis, multi-criterion analysis, input–output models, sustainability indicator indices, and optimization methods. Despite the availability of several assessment tools, there is a lack of proper standardization across all methods. The absence of standardization makes it challenging to compare and benchmark sustainable landscapes and buildings across multiple assessment methodologies because each one may utilize distinct criteria, categories, weighting systems, and documentation. Geographical variation in sustainable building assessments ensures that depending on elements like temperature, building codes, and cultural preferences, different assessment techniques may be more suited to certain geographical areas. A sustainable building assessment technique needs to consider regional variations when choosing an evaluation method or assessing the sustainability of the projects. A streamlined M&E regulatory policy for sustainability assessment is lacking in Kenya, contrary to the constitutional requirements of ensuring compliance with the principles of good governance. This gap should be addressed by ensuring that these existing strategies are incorporated into the Kenyan AEC industry specifically in ongoing landscape projects. According to ^[10], “policy framework and implementation significantly influences the implementation of monitoring and evaluation practices”. Similarly, the support from top management, improved budgetary allocations, and stakeholder involvement affect the success of monitoring and evaluation practices, thus creating a holistic approach to M&E. The periodic monitoring and evaluation of sustainable practices should be subjected to a log frame, therefore ensuring that the output of landscape project planning is achievable and provides measurable results that can be used to improve sustainability compliance. All stakeholders should be involved in the assessment of landscape sustainability through defining the scope, prioritizing indicators, establishing targets, determining indicator values, analyzing trends and tradeoffs, and identifying good practices. This ensures the maximum assessment of sustainability goals in landscape architecture projects. According to ^[11], sustainability is not a final state to be achieved; rather, it is an ongoing process that should emphasize social and institutional processes to assimilate good practices. Therefore, continuous monitoring and evaluation is expected to ensure the identification of good practice, to guide decision making, and to facilitate the achievement of goals set by all stakeholders.