Cities in developing countries are urbanising at a rapid rate, resulting in substantial pressures on environmental systems. Among the main factors that lead to flooding, controlling land-use change offers the greatest scope for the management of risk. However, traditional analysis of a “from–to” change matrix is not adequate to provide information of all the land-use changes that occur in a watershed. In this study, an in-depth analysis of land-use change enabled us to quantify the bulk of the changes accumulating from swap changes in a tropical watershed. This study assessed the historical and future land-use/land-cover (LULC) dynamics in the River State region of the Niger Delta. Land-use classification and change detection analysis was conducted using multi-source (Landsat TM, ETM, polygon map, and hard copy) data of the study area for 1986, 1995, and 2003, and projected conditions in 2060. The key findings indicate that historical urbanisation was rapid; urban expansion could increase by 80% in 2060 due to planned urban development; and 95% of the conversions to urban land occurred chiefly at the expense of agricultural land. Urban land was dominated by net changes rather than swap changes, which in the future could amplify flood risk and have other severe implications for the watershed.

Globally, cities in developing countries are urbanising at alarming rates, and a major concern to hydrologists and planners are the options that affect the hydrologic functioning of watersheds. Environmental impact assessment (EIA) has been recognised as a key sustainable development tool for mitigating the adverse impacts of planned developments, however, research has shown that planned developments can affect people and the environment significantly due to urban flooding that arises from increased paved surfaces. Flooding is a major sustainable development issue, which often result from increased paved surfaces and decreased interception losses due to urbanisation and deforestation respectively. To date, several environmental assessment studies have advanced the concept of alternatives, yet, only a small number of hydrologic studies have discussed how the location of paved surface could influence catchment runoff. Specifically, research exploring the effects of location alternative in EIAs on urban hydrology is very rare. The Greater Port-Harcourt City (GPH) development established to meet the growth needs in Port-Harcourt city (in the Niger Delta) is a compelling example. The aim of this research is to examine the relative effect of EIA alternatives in three different locations on urban hydrology. The Hydrologic Engineering Centre’s hydrologic modelling system (HEC-HMS) hydrodynamic model was used to generate data for comparing runoff in three different basins. HEC-HMS software combine models that estimate: Loss, transformation, base flow and channel routing. Results reveal that developments with the same spatial extent had different effects on the hydrology of the basins and sub-basins in the area. Findings in this study suggest that basin size rather than location of the paved surface was the main factor influencing the hydrology of the watershed.

The sudden emergence of the novel coronavirus (SASR-CoV-2) known as COVID-19 has had not only significant epidemiological effect on global population (WHO, 2020), but an adverse ripple effect is being felt by key economic sectors globally, especially in the UK (Al Amri & Marey-Perez, 2020; Jallow et al, 2020). Currently, as over 1.6M have died (65,520 in the UK) and figures continue to rise (Worldometer, 2020), the UK government and others around the world are taking dramatic steps to slow the spread of the virus to save lived. However, the measures taken are also having massive implications for economic activity (Allas et al, 2020; Scally et al, 2020). For example, because of widespread falls in services, production and construction output, the UK GDP experienced the biggest monthly fall (20.4%) since 2007 in April of 2020, The UK's construction industry presently the second largest industry contributing 7% of GDP (HoC, 2020) is currently under stress due the pandemic (ARUP, 2020; Jallow et al, 2020; Jones et al, 2020). The purpose of this study is to identify the Covid-19 risk associated with the construction industry, and ways to mitigate the risk. The main body of this study cover the associated risks, performance of the industry, exiting and finally proposed mitigation measures.