Engineering Solution of Collecting and Storing Rainwater Underground
Rainwater can be collected or harvested from the roofs of homes, greenhouses, garages, and other raise structures. That is only under a condition that there are gutters and a downpipe that joins the drain at ground level. Water butts with rainwater diverters are devised to fetch water from the downpipe. Moreover, the latter can also let the overflow enter the drain at the same time. A rainwater harvesting system comprises components of various stages – transporting rainwater through pipes or ducts, filtration, and storage in tanks for reuse or recharge (Kozubal 2019).
Construction of the underground tank
A number of the techniques used for constructing surface tanks can also be applicable for underground reservoirs. They are built in excavations with the soil being backfilled to surround the container once it is completed. In a situation of existence of such soil as clay or loess, it is more likely that the unlined sub-surface reservoirs are going to be constructed. Invariably these are prone to issues related to seepage evaporation and poor water quality (Reed 2017).
Procedure
Excavation of underground tanks is carried out either by “hollowing out method” or “open excavation method”. The former applies in areas where the sub-soil is firm enough. It entails digging by starting from the top downwards as it hollows out as the pit stretches downwards. The latter is utilized in areas where the sub-soil is relatively weak so as to avoid chances of the pit collapsing when digging in (Reed 2017).
Construction of the top roof structure is done after the tank is completed particularly in areas with firm subsoil. In that regard, the latter tanks are only plastered by using clay mud or mud mortar or cement mortar to control seepage. On the other hand, areas with weak and looser soil lining should have their tanks constructed by using unlined sub-surface tanks. However, they are likely to suffer from seepage, evaporation and poor water quality (Traboulsi 2017).
Summary
Underground water storage tanks are meant to bring about water security, especially during dry seasons and when there is a crisis of clean water. The initiative aims at using engineering construction methods to improve methods of water storage, especially on a large scale level. The water stored can be used domestically for human consumption as well as economically for irrigation. There are various types of water storage tanks coming in multiple shapes and sizes. Underground water storage projects help in utilizing the underground space and increase the ground space for other uses. Construction of these tanks varies depending on the strength of the soil in which they have to be constructed or rather the soil type. All in all, every kind of soil, regardless of the strength or weakness an approach is always available for building a tank.
Opinion
The reception of the method in most homes and even commercial firms is always very high. Most of the people are always in need of water independence. However, in some places, preferably rocky areas, digging boreholes is not always guaranteed that one is going to reach the water table before a rock bars them. So then, the underground water storage initiative is the best as far as rainwater is harvested. The cost of drilling water is way too high for everyone to afford. In that case, construction of underground rainwater storage units helps most people in many neighbourhoods to have sufficient water supply even during the dry season.
Reaction
Although ground catchment systems are most at times used to harvest rainwater for drinking purposes, it is never guaranteed that this water is safe for drinking or consumption in general. Unless treatment steps are taken to prevent micro-organisms from breeding in the water hence contaminating it (Kozubal 2019). Also, soil surfaces over which runoff water flow may have loosely held soil particles that are too small enough to pass through the filtering system. These particles eventually accumulate at the bottom of the tank forming silt and in the long run reducing the capacity of the tank. Also, untreated of catchment surfaces lead toinfiltration, eventually reducing the runoff from natural surfaces. Applying cement, butyl rubber, lime, paraffin wax oil, bitumen and asphalt to soil surfaces helps a lot in sealing and reducing infiltration (Traboulsi 2017).
Importance of the Problem
The problem has brought about a new method with which rainwater can be used to harvest rainwater that would otherwise turn into the runoff. Collection of the water and using it for purposes such as greywater, and irrigation, the capability to utilize a free source of water that would have otherwise gone wasted reduces environmental impacts (Schaffer 2019).
The problem does enable researchers to identify a solution fit for places where space is limited. In such situations, underground tanks can be constructed under driveways or lawns.
Future of the Problem
Underground water storage project is coming forth as one of the most modern ways of water storage and most notably the one that cares much about limited space management. As a matter of fact, the project is gaining more popularity on small and large scale capacities. Most homes, especially in urban areas as well as those in dry, regions have recently opted for underground methods of saving water.
Underground rainwater storage units are the most preferred given that heavy rainfalls are enough to provide massive water for storage over a long period of time. More so, human demand for water security is on the rise pending changing climate patterns (Kozubal 2019).
Over 1 million giant firms have been confirmed to have built underground water reservoirs to gather for their massive demand for water for running various processes. In that case, many firms are using the approach to draw more rainwater for future water security and perhaps to reduce the cost of acquiring enough water to cater for the enormous water uses (Schaffer 2019).
So many underground rainwater storage projects are underway, especially those initiated by various governments of the world in the quest of securing the future of its citizens in terms of water demand and supply. In summary, the rainwater harvesting and underground water storage are picking the attention of many solution seekers. Indeed it is a solution for acquiring free water for future use.
Reference
Ding, E., Ferster, C., Jarvis, T., Nhung, S., Rodstrom, J., & Schaffer, E. (2019). Stadium Neighborhood Underground Parkades and Water Storage
Traboulsi, H., &Traboulsi, M. (2017).Rooftop level rainwater harvesting system.Applied Water Science, 7(2), 769-775.
Wiley, J., Janda, A., Janda, S., & Reed, T. (2017). U.S. Patent No. 9,809,960. Washington, DC: U.S. Patent and Trademark Office.
Wroblewski, R., &Kozubal, J. (2019). Finite element and analytical stochastic models for assessment of underground, reinforced concrete water storage facilities and results of their application. PloS one, 14(1).