Investigating the Causes of Delay in Construction of Urban Water Supply and Wastewater Project in Water and WasteWater Project in Tehran

Abstract

It is obvious that providing drinking water in cities, especially in metropolises such as Tehran, as a political-socialeconomic center of the country is important. During the last decades, climatic changes, the decrease of raining, the increase of water harvesting from groundwater as well as the increase of population have intensified the importance of water in Tehran. Therefore, every change from water consumption to collecting, purifying and storing drinking water in the city reservoirs is highly critical. In the present study, the causes of delay in such projects have been determined based on experts' opinions about several concrete implemented reservoirs obtained by questionnaire and the related literature. Given to three classes pertained to such projects (employer, consultant and contractor), an initial questionnaire was provided to poll the experts' opinions and distributed among the sample of the study. In this regard, 45 Likert-scale questionnaires were equally distributed among three population; after gathering, the items with higher mean scores were selected for the main questionnaire (totally, 17 items). Using AHP method, the most important factors were identified and ranked through Expert choice Software. As the research findings revealed, failure of employer to pay to contractor timely, failure to obtaining the necessary permissions by employer before noticing to contactor to proceed, and uncertainty and buying project site by employer are the most important factors respectively.

The design for wastewater treatment plant (WWTP) with GPS X modelling

“…As some circumstances happed in the last decades such as climate change, enhancement of population, decrease of raining, as well as increasing in water harvesting from groundwater, thus the importance of water is intensified as the project of water and wastewater treatment. Based on this study, it is verified that some factors contributed in the delay of wastewater treatment projects such as uncertainty and buying project site and failure in paying to contractor and employers (Feyzbakhsh et al, 2017).…”

“…In Feyzbakhsh, Telvari, and Lork (2017)study, it is presented the delay in some project in Tehran City regarding to the three factors which are quality, cost and time. As some circumstances happed in the last decades such as climate change, enhancement of population, decrease of raining, as well as increasing in water harvesting from groundwater, thus the importance of water is intensified as the project of water and wastewater treatment.…”

Causes, Effects, and Mitigation Measures of Time and Cost Overruns in Water Supply Projects: Case of Tigrai Region, Northern Ethiopia

“…Similarly, inconsistency of price of materials was identifed as the fourth cause of cost overrun in water construction projects in Iran [20]. It was, however, ranked as the eleventh cause of time overrun in construction of water supply projects in Tehran [23]. Tis is due to the fact that Ethiopia and Iran have diferent market conditions, in which price of materials is expected to be diferent due to variable infation rates.…”

Delay Factors in Building Construction Project of State Elementary School

“…In our observation, a lot of projects have been done for the construction project of government school buildings in Indonesia is also delayed in its implementation caused by a lack of competent resources in its fields, so that, the government, contractors, and consultants have to change the existing and usual implementation process of building construction project that has been carried out so far. Thus, indications of construction delay factors such as financial constraints (Doloi et al 2012) [3], human resources (Yang et al 2010) [4], scheduling methods such as work plans that are not well-structured (Assaf and Al-hejji 2006 [5]; Hossain et al 2019 [6]; Yau and Yang 2012 [7]; Yang et al 2010 [4]), implementation methods related to failures the contractor in carrying out the work (Feyzbakhsh et al 2017 [8]), design changes involving incomplete drawings and specifications (Yau and Yang 2012 [7]), material availability (Assaf and Al-hejji 2006 [5]; Yang et al 2010 [4]), shortage of equipment (Assaf and Al-hejji 2006 [5]) can be anticipated.…”