A wastewater treatment system consists of a series of physical, chemical, and biological processes that aim to eliminate the contaminants present in the water. The objective of the research is to evaluate the wastewater treatment systems of the Punta Carnero sector, Ancón and Anconcito parish, through an experimental descriptive investigation to know the impact generated by the contamination parameters due to the incorrect treatment of these with respect to the analysis. of its efficiency and final discharge from the urban-rural area of ​​the Province of Santa Elena. The removal efficiency of pollutant loads was evaluated in percentage and the final discharge by the mean and standard deviation from 2015 to 2020. It was determined that the Ancón and Anconcito systems have better removal efficiency than Punta Carnero., however, the percentage is not optimal. The discharge of fecal coliforms, chemical oxygen demand, total suspended solids, and surfactants in none of the systems complies with the maximum permissible limits of Ecuadorian regulations. It was known that these systems generate negative impacts on health and the environment of the sector under study.

The instability of the energy supply, growing demand and the need to reduce carbon emissions are priority challenges in developing countries such as Ecuador, where power outages affect productivity and generate economic losses. Therefore, solar energy is positioned as a sustainable alternative. The objective of this study is to evaluate a pilot photovoltaic (PV) system for residential housing in coastal areas in the Santa Elena province, Ecuador. The methodology included the following: (i) criteria for the selection of three representative residential housings; (ii) design of a distributed generation system using PVsyst software; and (iii) proposal of strategic guidelines for the design of PV systems. This proposed system proved to be environmentally friendly, achieving reductions of between 16.4 and 32 tonnes of CO₂ in the first 10 years. A return on investment (ROI) of 16 years was achieved for the low-demand (L) scenario, with 4 years for the medium-demand (M) scenario and 2 years for the high-demand (H) scenario. The sensitivity analysis showed that the Levelized Cost of Energy (LCOE) is more variable in the L scenario, requiring more efficient designs. It is proposed to diversify the Ecuadorian energy matrix through self-supply PV systems, which would reduce electricity costs by 6% of consumption (L scenario), 30% (M scenario), and 100% (H scenario). Although generation is concentrated during the day, the net metering scheme enables compensation for nighttime consumption without the need for batteries, thereby improving the system’s profitability. The high solar potential and high tariffs make the adoption of sustainable energy solutions a justifiable choice.

The Santa Elena Peninsula has experienced local subduction earthquakes in 1901 (7.7 Mw) and 1933 (6.9 Mw), during which local ground conditions, including deposits of longshore-current sediments, paleo-lagoon or marsh, sandspit, and ancient tidal channel sediments, exhibited various coseismic deformation behaviors in Quaternary soils of inferior geotechnical quality. This study shows that geophysical profiles from seismic refraction and shear-wave velocities are correlated with stratigraphic data from sedimentary sequences obtained from slope cutting and geotechnical drilling. This database is used to create a comprehensive map to describe the lithological units of Salinas’ urban geology. The thickness of the Tertiary–Quaternary sedimentary sequences and the depth to the bedrock of the Piñon and Cayo geological formations determine the periods of sites in these stratigraphic sequences, which range from 0.3 to 1.5 s. This study provides the first geotechnical zoning map for the city of Salinas at a scale of 1:25,000, which is a technical requirement of the Ecuadorian construction standard. This geotechnical zoning information is essential for appropriate land management in Salinas and its neighboring cities, La Libertad and Santa Elena, as well as for outlining municipal restrictions on future construction.

The indiscriminate use of plastics has led to an environmental crisis due to inadequate disposal and prolonged degradation time. Among them, polyethylene terephthalate (PET) is widely used in food packaging and textiles, significantly contributing to plastic waste generation. This study investigates the incorporation of PET fibers into concrete as a sustainable solution within the framework of the circular economy. Experimental tests were conducted to evaluate the mechanical properties of concrete with PET fiber additions at different dosages (2%, 3%, 4%, and 5% relative to cement weight) and in two forms (smooth fibers and accordion-shaped fibers). The results showed that adding 2% smooth PET fibers increased compressive strength by 3% and flexural strength by 12.6%, while higher percentages negatively affected material resistance. The findings highlight the potential of PET-reinforced concrete as a viable alternative to reduce plastic waste and enhance material performance in construction.

Steel is the most used material for concrete reinforcement; however, it performs poorly in aggressive environments (e.g. coastal areas) owing to corrosion (moisture and chlorides). This study aims to analyse the tensile strength of steel and glass fibre-reinforced polymer (GFRP) bars through laboratory testing to assess their feasibility and application in construction. Steel bars were tested by ASTM E8/E8M–22, obtaining values of 606.61 MPa (Ecuador) and 676.46 MPa (Peru), whereas GFRP bars were tested following ASTM D7205/D7205M–21 (1,000 MPa). The analysis indicated that GFRP bars offer structural advantages (suitable for elements in coastal zones with low to moderate seismic activity), environmental benefits (lower CO₂ emissions during production), and enhanced durability (corrosion resistance).