Baldwin et al. [1] , state that construction waste is produced from a range of construction activities and materials. However, it is must be mentioned that not every activity and material will produce equal amount of construction waste. According to Arslan, et al. [2] , sources of waste include unused materials, incorrect materials, surplus stencils or nails, packages of construction materials or components, surplus concrete materials resulting from fractures or deformations due to improper storage or preservation of construction materials and components arriving at the construction site. Others include poor material handling, erroneous cuttings, improper or faulty equipment, poor storage facilities, poor workmanship and inaccurate measurements. Most of the waste generating factors identified above originate mainly from site operations and general residual, Osmani et al. [3] . With so many sources of waste generation, this study set out to investigate waste management practices in the Zambian Construction Industry (ZCI). While studies have been previously done in the field, this particular research aimed at measuring waste management practice and perceptions. Previous studies done in Zambia include minimising construction waste generation through design by Muleya and Muyoba [4] . Another recorded study done by Lwanga [5] , focused on the investigation on re-using construction waste for sustainable development with particular attention to concrete waste. Much of the research has in the past concentrated on household waste with little attention to other sectors such as construction. A study by Edema et al. [6] revealed that a study on the Copperbelt province of Zambia showed that lack of environmentally friendly, sustainable and affordable waste management had led to the wide spread open dumping and open burning of solid waste. In another study that included Zambia and reported in the Africa Review Report on waste management [7] , it was concluded that poor waste management practices in particular the widespread dumping of wastes in water bodies and uncontrolled dump sites aggravates the problems of generally low sanitation levels across the African continent.

This study finally considered the feasibility of respective perspectives of stake- holders regarding the use of a Site Waste Management Plan (SWMP) as a method of mitigating the generation of construction waste from the design through to the construction phase.

Construction site waste has been labelled to be one of the major problems in the construction industry that presents significant implications on the efficiency in the industry as well as the adverse impacts on the environment, Formoso et al., [8] . According to the United Nations Environment Programme [9] construction and demolition waste in the European Union made up 38.2% of the total waste generated in 2006. However, it has been stated that the solution can be found by including the waste management aspects in the planning process, carefully giving attention to the important issues it raises, United Nations Environment Programme, [9] . Based on the Africa review report on waste management [7] , which centres on four countries namely; Ghana, Egypt, Kenya and Zambia, it was stated that gaps exist that hinder environmentally sound management of waste. Some of the identified gaps include; Policy and planning, legal aspects including enforcement, key stakeholders roles and coordination, capacity building and training, public awareness, staff, equipment, finance and cost recovery, Mwesigye, et al. [7] . Commenting on the aspect of Policy and Planning at national level it was established that, in the Kenyan case it is still a significant challenge to enforce the law regarding waste management because of the absence of a National Waste Management Policy. The other problem established was that Waste Management Strategies or Plans have not been embraced by all stakeholders in the country, Mwesigye, et al. [7] . Mahayuddin et al. [10] states that construction waste represents large amounts of material that are often illegally dumped by roadsides, river banks and many other open spaces. Urgent and immediate improvement of the construction waste disposal practices is necessary to meet the current demand for improved construction waste management. However, there is very little relevant information on disposal practices for construction waste at the municipal level, including its composition and the disposal site characteristics. The lack of a collection network and insufficient collection of waste from construction sites contributes to illegal dumping. Guerrero et al. [11] carried out a study that included the city of Lusaka in Zambia on the solid waste challenges in developing countries. The study however only considered one city in Zambia and further, it did not consider construction waste. Mahayuddin et al. [10] further states that lack of sufficient legislation, enforcement and facilities have contributed to poor waste management of construction waste alongside other form of waste in developing countries.

It can be seen clearly that the absence of a Waste Management Plan or framework contributes to the poor management of waste. This is because there are no clear guidelines on how to best handle waste. It was further established that, most of the bidding documents used for building works in Zambia do not have provisions or guidelines that adequately promote sustainable construction waste management. An example would be clause 5.15 of the FIDIC document at Buildings Department Copperbelt Office of Zambia which states in part that the contractor shall, “keep the site clean, clear up and remove all rubbish and debris.” This clause does not give any further guidelines to ensure that waste is handled in a more sustainable manner.

However, the documents used in the road sector are clear in promoting sustainable waste management in Zambia. The Special Environmental Specifications section states that, “The contractor shall ensure that all waste including construction waste generated during execution of the Works, is collected and disposed off at designated disposal sites in line with the Waste Management Re- gulations of the Environmental Council of Zambia or shall be re-used or sold for re-used locally as approved by the Project Manager.” The statement goes beyond disposal to include other factors of sustainable waste management such as reuse, which is not the case for building works. The gaps in the management of construction waste constituted the motivation to carry out this research.

The main aim of this research was to investigate and categorise construction waste management practices in the Zambian construction Industry (ZCI).

Ÿ To investigate and categorise of common waste management practices in the ZCI.

Ÿ To investigate the feasibility of adopting a waste management plan in the ZCI.

Ÿ To establish and measure the challenges and benefits associated with the adoption of a site waste management plan in the ZCI.

According to Tam [12] , waste management in the construction industry has not been effectively controlled, and as a result more work must be done in order to reach a satisfactory level of waste management. In the recent past, construction waste was usually disposed in landfills, however, landfill spaces are fast being exhausted hence the need to consider other suitable means to manage construction waste. It has further been argued that construction waste generation and unsustainable use of natural resources as building materials, in the construction industry are related to the negative impact on the environment. It is estimated that approximately 10 to 30 percent of waste disposed of in landfills worldwide originate from construction and demolition activities, Papargyropoulou, et al. [13] .

This study was carried out in Lusaka and the Copperbelt provinces of Zambia, thus representing the Zambian construction industry. The two provinces were selected because they constitute the largest volume of construction works in Zambia. The selection of the two provinces was done through judgmental sampling because they were perceived to meet the requirements of the study as supported by Kumar, [20] . The target groups were basically divided into three groups namely contractors, consultants and government units as regulators. Consultants are responsible for design, specification provision and overall supervision of the construction project. The contractor on the other hand is responsible for the execution and delivery of the works during which waste is generated. Government is responsible for providing legislation and enforcing the law regarding waste management. All three stakeholders play a critical role in construction waste management hence the need to get independent perspectives of what was prevailing in terms of challenges associated with construction waste. Architects and quantity surveyors were selected to participate because they are at the core of project design and contract procurement procedure for building works.

Tables 3-5 gives a summary of the sample sizes selected for the research:

Tables 6-13 shows the frequency of responses obtained. The tables contain methods of waste management (factors) against the scale of responses (frequency distribution). This in turn enabled the identification of the factor with the highest frequency for the purpose of finding the most occurring method using the Relative Importance Index formula (RII) as given by Tam et al. [21] .

Or

where w is the weighting given to each factor by the respondent, ranging from 1 to 5 in which “1” is the least important and “5” the most important; A is the highest weight, in this study A = 5; N the total number of samples.

Considering disposal as an example, the following is how the formula is used;

The example above is based on the data collected from the field and applied in the formula.

From the literature review, the research findings and analysis the following conclusions were drawn from this research based on the set objectives. Disposal was the most frequently used method of construction site waste management in Zambia based on the sample target areas. This was attributed to the fact that disposal is the method that is commonly specified mode of waste management in the guidelines and contract documents as evidenced in the findings. Further it was concluded that the waste management practices in the ZCI do not fully conform to the waste management hierarchy. All the three categories of respondents indicated that a SWMP would be an effective means to safely manage construction waste in the ZCI. The most notable challenges identified included; Construction culture and behaviour, lack of experience/training and Low financial incentives. The benefits of adopting a SWMP based on the findings included: environmental benefits, reduced waste to landfills, and reduced waste on site and preventing pollution. Other supplementary benefits were that it would provide a formally structured approach to on site waste management and allocation of resources more efficiently. Regulators indicated their willingness to support a SWMP through incentives such as fines for offenders and halting of non- complying projects with deregistration being the last option. The study clearly indicated that there is unsustainable construction waste management practice in the Zambian Construction Industry. Further the practice presents a serious challenge of environmental damage and degradation. The situation can be corrected through training, awareness campaigns commitment incentives and involvement of all stakeholders in the introduction of SWMP as part of sustainable construction waste management in the Zambian Construction Industry.

Muleya, F. and Kamalondo, H. (2017) An Investigation of Waste Management Practices in the Zambian Construction Industry. Journal of Buil- ding Construction and Planning Research, 5, 1-13. https://doi.org/10.4236/jbcpr.2017.51001