Joseba R. Bayon

Performance of pervious pavement parking bays storing rainwater in the north of Spain

Pervious pavements are drainage techniques that improve urban water management in a sustainable manner. An experimental pervious pavement parking area has been constructed in the north of Spain (Santander), with the aim of harvesting good quality rainwater. Forty-five pervious pavement structures have been designed and constructed to measure stored water quantity and quality simultaneously. Ten of these structures are specifically constructed with different geotextile layers for improving water storage within the pavements. Following the confirmation in previous laboratory experiments that the geotextile influenced on water storage, two different geosynthetics (Inbitex and a One Way evaporation control membrane) and control pervious pavements with no geotextile layers were tested in the field. Weather conditions were monitored in order to find correlations with the water storage within the pervious pavement models tested. During one year of monitoring the three different pervious pavement types tested remained at their maximum storage capacity. The heavy rain events which occurred during the experimental period caused evaporation rates within the pervious pavements to be not significant, but allowed the researchers to observe certain trends in the water storage. Temperature was the most closely correlated weather factor with the level of the water stored within the pervious pavements tested.

Rainfall–Runoff Simulations to Assess the Potential of SuDS for Mitigating Flooding in Highly Urbanized Catchments

Sustainable Urban Drainage Systems (SuDS) constitute an alternative to conventional drainage when managing stormwater in cities, reducing the impact of urbanization by decreasing the amount of runoff generated by a rainfall event. This paper shows the potential benefits of installing different types of SuDS in preventing flooding in comparison with the common urban drainage strategies consisting of sewer networks of manholes and pipes. The impact of these systems on urban water was studied using Geographic Information Systems (GIS), which are useful tools when both delineating catchments and parameterizing the elements that define a stormwater drainage system. Taking these GIS-based data as inputs, a series of rainfall–runoff simulations were run in a real catchment located in the city of Donostia (Northern Spain) using stormwater computer models, in order to compare the flow rates and depths produced by a design storm before and after installing SuDS. The proposed methodology overcomes the lack of precision found in former GIS-based stormwater approaches when dealing with the modeling of highly urbanized catchments, while the results demonstrated the usefulness of these systems in reducing the volume of water generated after a rainfall event and their ability to prevent localized flooding and surcharges along the sewer network.

Design and construction of an experimental pervious paved parking area to harvest reusable rainwater

Pervious pavements are sustainable urban drainage systems already known as rainwater infiltration techniques which reduce runoff formation and diffuse pollution in cities. The present research is focused on the design and construction of an experimental parking area, composed of 45 pervious pavement parking bays. Every pervious pavement was experimentally designed to store rainwater and measure the levels of the stored water and its quality over time. Six different pervious surfaces are combined with four different geotextiles in order to test which materials respond better to the good quality of rainwater storage over time and under the specific weather conditions of the north of Spain. The aim of this research was to obtain a good performance of pervious pavements that offered simultaneously a positive urban service and helped to harvest rainwater with a good quality to be used for non potable demands.

Temperature Performance of Different Pervious Pavements: Rainwater Harvesting for Energy Recovery Purposes

Pervious pavements offer a solution for rainwater runoff treatment in urban areas, combining storm-water management with water reuse purposes when the sub-bases become rainwater reservoirs. Furthermore, the thermal behaviour research into these systems has demonstrated their contribution to palliating the urban heat island effect in the hottest season and to delaying freezing during the coldest season. Recent investigations related to pervious pavements and their sub-bases have enabled the use of these structures combined with Ground Source Heat Pumps (GSHP) in addition to the other well-known applications. The aim of this field study is to investigate the temperature response observations of the water stored in the sub-bases of different pervious pavements under specific conditions, in order to evaluate the possibility of introducing GSHP technology. The base and sub-base temperatures of different types of pervious pavements were monitored during one year and the results obtained show the differences in pervious pavements temperature compared to air temperature over the period of study; and demonstrate that the sub-base is less affected by the air temperature than the base, due to the insulating capacity of pervious pavements. On the other hand, water samples were taken from the different pervious pavement sub-bases in order to assess the water quality deterioration due to the temperatures reached in the sub-base, focused on investigating the presence of Legionella in this particular aquatic environment.

Monitoring and Evaluation of the Thermal Behavior of Permeable Pavements for Energy Recovery Purposes in an Experimental Parking Lot: Preliminary Results

Permeable pavements offer a solution for rainwater runoff treatment in urban areas, combining water management with water reuse purposes when the sealed subbase become rainwater reservoirs. Furthermore, the thermal behavior investigations of these systems have proved their contribution to palliate the urban heat island effect in the hottest season and to delay freezing during the coldest season. Increasing knowledge of heat-transfer mechanisms into the permeable pavements and their subbase has enabled the use of these structures combined with ground source heat pumps (GSHP) in addition to the other well-known applications. The aim of the present study is to investigate the thermal response observations of permeable pavements under specific weather conditions while paying attention to the temperature distribution in the subbase, where rainfall water is stored for others uses, to evaluate the possibility of introducing GSHP technology. The bedding layer and subbase temperature of reinforced grass permeable pavements was monitored during three months in summer 2008, and the preliminary results obtained show the subbase temperature different from the air temperature during the period of the study and demonstrate that the subbase is less affected by the air temperature than the bedding layer because of the insulating capacity of permeable pavements, explained through the heat-transfer processes that take place into the pavements.