Low cost artificial recreational coastal lagoon: Hydrographic, and design guidelines in development resorts

The objective of the research is to find low cost alternative for conventional recreational lagoons that consume water and energy used for desalination which is the only alternative for water treatment in most touristic villages all over the world. The study uses low cost recreational lagoon with new technology that use brackish water from deep wells and purify this water before entering the lagoon by controlled pulses and energyefficient ultrasound filtration. This allows to maintain the water within predefined parameters, guaranteeing standardized water quality in all lagoons. The research introduces the lagoon new technology and its low cost design including feeding and drainage wells, second, the hydrographic surveying for the coastline in the study area, third water quality modelling for the production and injection wells, fourth, use SOBEK 1-2 Mathematical Model for determine the water depth and perspective water volume for the designed lagoon. The aim of this model: Determine the relation between the water depth and the water volume for the canal and the lakes. Second, calculate the evaporation rate from the surface, Determine the number and capacity of the water wells needed to fill the canal and the lakes, and Find out the relationship between the discharge and the time needed to circulate the water in the canal and the lakes to keep their water quality. The results of the measurements from the observation well prove that the optimal discharge per each well is 0.022 m³·s^–1. The construction of suggested new green technology lagoon are very low cost, completely environmentally friendly, in addition fulfils the highest standards of environmental safety.