The performance of Sand and gravel filter for artificial ground water recharge was evaluated at the Ground Water Project, MPKV, Rahuri during 2004–05. Different locally available filter materials viz; sand, angular gravel, pea gravel and coal were tested independently and in combination of two, three and four layers with varying layer thickness of 15, 30 & 45 cm, respectively. Effect of filter material on filtration was studied by recording observations on inlet and out-let head, velocity of flow, time of filtration and filtration efficiency. Under varying suspended load concentration in single layer filter, maximum filtration efficiency (79.06%) was observed for sand grade (I) 45 cm thickness with average velocity of flow, 1.91 cm/sec & average time of filtration 67.33 min. The two layer filter with sand grade (I) 45 cm thickness & coal layer of 15 cm thickness has given maximum filtration efficiency (81.62%). The average velocity of flow and average time of filtration were 5.4 cm/sec and 66 minutes, respectively. The three layer filter consisting of angular gravel grade (I), pea gravel grade II with 45 em of thickness of each layer combined with coal grade (I) 15 cm thickness has given maximum filtration efficiency (83.42%) with average velocity of flow as 6.18 cm/sec and average time of filtration as 61.57 minutes. The four layer filter has given maximum filtration efficiency (97.21 %) when used with three different layers of filter material Sand grade I, pea gravel grade I, angular gravel grade I of thickness 45 cm each along with coal layer of 15 cm thickness. The average velocity of flow and average time of filtration were 6.28 cm/sec and 115.18 minutes, respectively. It is concluded from the study that the four layer sand arid gravel filter has performed better than all other multilayer filters.
