|M.Sc Student||Miron-Phstiner Sigalit|
|Subject||Water Sensitive Urban Planning Towards Planning Guidelines.|
|Department||Department of Architecture and Town Planning||Supervisors||Professor Emeritus Naomi Carmon|
|Professor Emeritus Uri Shamir|
The ultimate objective of this research is to make planning recommendations which will minimize the adverse effects of urban development in Israel’s coastal plain on the aquifer. It is widely accepted that urbanization cause an increase in surface runoff rates and volumes, and pollution of the water, which leads to a corresponding decrease in groundwater recharge and deterioration of the quality of the water recharged into the aquifer. This research is aimed determining the potential for mitigating the adverse effects of urbanization on groundwater quantity and quality, through appropriate urban planning, and by incorporation of certain types of facilities in the urban fabric.
A literature survey pointed at the difficulties in direct measurement or computation of the effect of various land uses groundwater quantity and quality. Hence, an indirect method was selected to assess the effect on recharge: the SCS (U.S. Soil Conservation Service) method. According to this method, different types of land use are fitted with a Curve Number (CN), which in calculating the runoff volume as a fraction the rainfall volume of a storm. The increase in runoff volume caused by urban land uses is taken to mean an equal in groundwater recharge.
As an example, an urban site in Israel’s coastal plain was selected: the “Kiryat Ganim” neighborhood in Rishon-Le-Zion may be considered representative of typical current and potential future urban development in Israel. The results of applying the SCS method to this neighborhood indicated the potential loss to groundwater recharge caused by urban development: an average annual decrease of 69,000 m/year in recharge per square kilometer.
A review of the literature revealed a number of facilities and “technologies” that may mitigate the effects of urbanization on groundwater. The effect of one such “technology” was examined: connection of all roof drains directly into the ground, instead of the drainage system. The results show an addition of some 28,000 m3/year to the recharge, relative to the situation with the roofs connected to the drainage system.
From the results obtained we may draw the following conclusions: 1) There is a significant reduction in groundwater recharge due conventional urbanization. 2) The negative effects on groundwater recharge may be lessened by developing appropriate urban planning guidelines, especially with regard to the land cover surrounding housing and public facilities and to the integrating of certain local low-cost technologies which have a significant positive effect on groundwater recharge into the urban fabric. 3) Further research is required to determine more conclusively the effects of urbanization on groundwater quantity and quality, and on the potential efficacy of using “mitigating technologies” in the urban fabric.