Dear Sneha.

There are probably many possible approach all depending on the amount of EPS you expect. You can directly precipitate EPS from filtered water and then quantify it by either Dubois or Alcian blue assay. This worked for me quite well in setting where there was quite a lot of EPS. You can also stain the filter using the Alcian blue 8GX, this might be more appropriate for low concentrations. The reference below might be helpful.

Passow U and AL Alldredge. (1995). A dye-binding assay for the spectrophotometer measurement of transparent exploiter particles (TEP). Limnol Oceanogr. 7:1326-35.

Bober, C., Mojica, K. and Cooney, M., 2005. Quantification of single-species marine biofilm with alcian blue. Journal of Young Investigators, 12(4), pp.1-4.

Also you might be able to use lectin staining, but this might be expensive. There might be other methods to detect EPS, but these are the simplest for a first screening and quantification.

Best