Site Selection:

Your intake strainer should be located at least eighteen inches off the bottom to avoid sediment and at least twenty four inches below the waters surface at low water to avoid cavitation. Ice depth must be taken into account in areas of Winter freeze-up. In our latitude we can get three, sometimes up to four feet of ice forming on calm water so I like a site with a minimum depth of seven feet at low water. This puts the strainer five feet below the surface. A portable depth sounder is a handy tool for the site selection and planning process. The rise, or lift, from the waters surface to the top of the hydrant head should be kept under 16 feet for properly maintained "class A" fire service pumps. Don't forget to consider an easement agreement if your hydrant is to be installed on someone else's property.

Permits and silt screening:

may be required in your area to protect the environment and fish habitat. Fish will not spawn on sand or silt.  The silt from the excavation can settle over great distances underwater, so the excavation and equipment should remain inside a silt screen barrier. Any equipment entering the water should be clean and free of oil. Fuelling must be done well away from the waters edge. Rock, (rip rap) has been recommended as a top dressing to the underwater excavation as the fish will spawn on rocks. Check with your local authorities.

Installation:

The schedule 40 or 80 PVC pipe should be assembled at least 24 hours in advance of trenching to allow all glue joints to cure. But don't leave pipe laying around for weeks because it is susceptible to degradation by the sun’s ultra violet rays. Each joint should be cleaned and prepped with a clean dry cloth then lightly scuffed with sandpaper to remove gloss then cleaned again. Both joints should then be primed and liberally coated with heavy duty PVC glue. Note instructions on container regarding minimum and maximum working temperature and please observe cautionary notes. You have a matter of seconds before the bond begins so have some assistants on hand to wrestle the pipe joints together. The joint, once made must be held in place for at least 30 seconds so the exothermic reaction set off by the glue and primer can't push the two sections apart. Don't attach the hydrant adapter at this time, leave the riser a little longer than required and cut it off after the finished grade elevation is established. Once the rise and run of the pipe has been assembled and allowed to cure for approx. 24 hours the trench can be excavated. The depth of the trench must be consistently close to level from where it begins out in the water to where it ends just beyond the location of the riser. The most important consideration is that the horizontal run of pipe always remains under water. Prior to installation the strainer can be bagged and taped with a green garbage so that the whole system may be floated into position. The pipe is then lowered into the trench by ropes attached along the length of it and handled by an adequate number of assistants from both sides of the trench. (No-one should be allowed in or near the trench at any time as wet and sandy soil conditions are prone to collapse.) The riser should be roped at the bottom and top from both sides to allow proper placement while backfilling. Once in position a skilled individual in a small boat can remove the bag from the strainer. At this time the riser should be held high in the water to allow all air to escape from the pipe as it sinks. It is recommended to fill below and around the pipe with gravel to help protect the pipe before backfilling. Don't let the equipment operator push down on the pipe or pack the fill with his shovel until the whole pipe is well covered with the fill material. An uneven bottom can stress and bend the pipe under the force of the shovel and result in changing the elevation of the strainer or breaking the pipe joints.   When the trench is filled the riser can be cut to about 24" above the finished grade. Most importantly the hydrant adapter should be installed at an elevation that is below the intake of the responding pumper. All exposed p.v.c. (above ground) can then be scuffed with a wire brush, cleaned, primed and painted with acrylic enamel or epoxy based paint, one coat primer and two coats paint for u.v. protection. Tremclad spray paint also seems to work well. Six inch pipe performs well in lengths up to about 65 feet; longer installations should utilize larger pipe diameters. Where required the strainer is supported by inserting a 1 inch pipe through the existing holes and installing a strainer support clamp.

In areas of Winter freeze-up:

We use two inches of fibre-glass pipe insulation on the riser, above the water line, wrapped in 6 mil poly and taped with sheathing tape and sealed with polyurethane caulking to keep it dry. (Wet fibre-glass loses its insulating ability.) This helps contain some of the heat loss from the water source and ground. Styrofoam pipe wrap is preferred. Where insulation is used and where damage to your hydrant is a concern a sono tube and concrete can be installed around the exposed pipe for protection. As an alternative a larger diameter pipe and cap can be used as protection instead of concrete. This outer protective layer should also be painted for maximum visibility and u.v. protection. Bollards can be installed to protect the pipe and a chain hung between the two will support the pumper truck hard suction hose and prevent damage to the dry hydrant connection.

*Important*

*Care must be taken to ensure a safe site as wet soil conditions are prone to cave-in. No-one is to be allowed in or near the trench.    Your pipe should be assembled and ready to go in by rope just as soon as the trench is done.