Incidentally, for S.Hs. and MDRs the duration of permissible interruption is 12 hours at a time and upto 6 times in a year. Perhaps we could adopt 24 hours instead of 3 days. The minor bridges and culverts on branch roads leading to individual villages may be designed for 24 R class of IRC loadings except where special circumstances warrant higher loadings. For other rural roads 40 R class of IRC loading may be used for design of these structures. For speedy construction of good quality for minor bridges, precast concrete beams could be used, wherever possible, to minimize skilled work at site.

Regarding major bridges, it is stated that these are generally not constructed under the MNP. The idea is that, as far as possible, the approach roads to villages should be so aligned that they are not required to cross very large rivers or streams requiring bridges longer than 30 metres. Instead, use is to be made of bridges constructed on higher categories of roads in deciding the take off point of approaches from the main road. In some cases a major bridge might become unavoidable due to the geography or due to the economic ties of the village in a particular direction. A conscious decision will have to be taken in each individual case.

In most parts of the country, the streams fun dry after only a short period after the end of monsoon. The water table is getting lower and lower due to more and more borewells being dug and exploited. Drinking water for cattle becomes scarce. It is, therefore, suggested that bridge-cum-bandharas be built on a large scale, taking advantage of the large number of bridges that will be built in this programme. It is realised that conditions at site may not be suitable for an economical bridge-cum-bandhara. But, wherever possible it should be tried. Several such bridge-cum-bandaras are in operation in Maharashtra. In such bridge-cum-bandharas post monsoon flow is blocked at the upstream edge of the bridge and a small storage is created at low cost. This stored water is not only useful for cattle, as drinking water, for irrigation etc. but it also raises the water table by percolation of the stored water. Typical sketches of bridge cum bandharas are enclosed as Annexure-8.

In some cases it may be possible that while we construct black topped roads