# Groundwater and Urban Planning Perspective
## 4 Conclusions and Recommendations  
The analysis of the support studies of the Urban General Plans for 17 Romanian cities showed that urban planning documents do not sufficiently rely on groundwater information. Corresponding hydrogeological studies include only general recommendations, and these do not include specifications targeting reliable water-balance preservation or detailing the necessity of implementing monitoring systems to survey groundwater levels. These do not recommend either special constructive measures to be implemented for future infrastructure elements and do not include maps delineating particular geotechnical and hydrogeological characteristics. The analysis of Bucharest clearly shows that anthropogenic influences severely alter the water cycle in urban areas. The change in the water cycle induced by urban areas directly affects the groundwater level. Increasing groundwater levels can lead to flooding while lowering groundwater levels can lead to subsidence. The construction of high-rise offices or residential buildings, made in several locations in the Colentina study area, create basements on several levels, which makes the extension of the buildings exceed 10 m in depth. This leads to the use of dewatering systems required to locally reduce the hydraulic head of the shallow aquifer to ease the construction work and later allow for the optimal use of the basements. In the case of the intensive development of the subsurface constructions, the associated procedures of lowering or raising the groundwater level would have a strong impact on the neighboring infrastructure elements or networks. Depending on the pumped volume of the groundwater, this operation can have effects on the aquifer dynamics and can lead to displacement of the land surface, water level decrease in neighboring lakes, and the instability of infrastructure elements or changes of their hydraulic interaction. The vertical displacement of the earth's surface generally has a combined cause, involving problems of geotechnics, hydrology, hydrogeology, and geological aspects. Since elements in urban areas both underground and aboveground are exposed to more factors than in the extra-urban area, it is very difficult to accurately identify the causes and effects of certain phenomena that occur. The historical component of this problem is that in the past various works were carried out without keeping coherent and concrete records of the work process. In the rare cases where this information exists, it is not sufficiently detailed. Increasing awareness of the strong linkage between urban development and groundwater is necessary for urban planners and decision makers because of the urgent need for applying coherent and correct city guidelines that consider both aboveground and underground development, including groundwater management. Accurate analysis of urban groundwater should be performed with two considerations: (1) the resilience of city development, and (2) groundwater resource protection. The first consideration focuses on the unfailing development of city infrastructure in terms of its ecological resilience as well as land stability, preventing the delay of construction projects and cost overrun, and of subsequent damage to urban infrastructure [3]. The second consideration emphasizes the qualitative and quantitative protection of the entire aquifer system the city is laying on. Underground city management could be performed by implementing a service within the municipalities in charge of data and decision-making concerning geology, groundwater, and the subsurface infrastructure elements and networks. This management should directly cooperate with the main actors represented by the city institutions and professional groups.