Lining a Pond
One question that comes up whenever we think about ponds is lining. What lining and how much does it cost? So here it is: we’ve compiled a step-by-step guide on how to prepare a pond for lining, the three different lining methods we’ve used in the past and how much they’ve costed us. These are, of course, not the only ways to line a pond, but these have worked well in our experience so far
PREPARING A POND FOR LINING
(The legend for the numbered images is below them)
Before lining, we need to achieve smooth, gentle and compact pond slopes. Normally this is possible if you tamp the ground with a dimus. However, if the slopes are too rugged, follow the below steps:
1. Pile up some soil near / within the pond
2. Add water to the soil and mix until the soil attains a consistency that can be used to easily plaster out the ruggedness of the pond slopes
3. Use a mamati to plaster the rills / ruggedness
4. Use your hands to do the finer smoothening
5. You’re now ready to start the lining process!
METHOD 1: LIME PLASTERING
1. The unlined pond that we have used to demonstrate this method
2. Fill a bucket with lime and hydrate for 24 hours
3. Ready the other two elements of the plastering mix (sand & soil). The soil needs to be sieved to remove bigger lumps of gravel from it
4. With the lime slurry, sand and sieved soil, try a few mixes. Start with a lime: sand: soil ratio of 1.5 : 1 : 1.5 and then adjust from there based on the texture. Create your mix, the texture should be similar to cement used for wall plastering - not too runny, but easy to work with. It’s called the workability of a mix
5. Test the selected mix before working on a larger pond
6. Line the sides of the pond with chicken mesh for additional support to the plastering. Nails could be used to hold the chicken mesh close to the pond slopes. In situ ferro lime is what we call it
7. Use the water that you scooped from the bucket of hydrated lime to wet / moisten the walls of the pond for better adhesion
8. Start plastering, the first layer should be at least two inches thick. Let it dry, then cover with damp hessian and allow to cure for a few days. If needed, do another layer
9. After a few days, paint with a plaster of hydrated lime and clay water (put soil in a bucket with water, mix and remove the top layer for clay)
10. Once set, seal with soap water (1 part soap and 20 parts water), repeat two or three times and allow to dry between applications
Overall Cost - INR 300 per square meter
METHOD 2: GUNNY DIP
1. Cut the gunny sacks into pieces
2. Make the cement dip by mixing cement and water together. We should achieve a paint-like consistency with the cement dip
3. Dip the gunny sack into the cement dip
4. Start laying out the gunny sacks. Plan the work flow beforehand (i.e. where you’ll start doing the lining and how you will progress, so you don’t have to step on the areas that have already been laid with gunny sacks dipped in cement)
5. Here we've lined the slopes first and we're ready to line the pond’s center / bottom. Remember to pat all areas of the gunny to ensure no air spaces remain. When you move to the adjacent area, overlap a part of your next gunny sack over the previous one to ensure no gaps. If required, do two layers
6. Cure the cement lining for a few days by placing gunny over the lining and watering the gunny sacks
Cost - INR 200 per square meter
METHOD 3: GEOTEXTILE
1. Leaving space for a shelf / bench around the pond, dig a trench around the bench / shelf
2. Tuck the geotextile lining into the trench and place heavy rocks in the trench to hold the geotextile in place. You can also place rocks randomly within the pond to address the issue of the liner floating in the water. Seams and wrinkles are best avoided, however, if you end up with them, place rocks on them. Usually geotextiles vendors are well versed with avoiding / dealing with seams
3. Cover up the trench with the soil piled from the trench digging and level out the trench with the shelf / bench
Cost - INR 110 - 170 per square meter
