DESIGN PROCESS Jan 2022.doc

DESIGN ASSIGNMENT - Due Thursday Feb 26, 2026 Using the plan provided layout an irrigation system for the lawn and shrub bed areas . Hand in a plan showing sprinkler layout and circles used to determine lawn coverage a sheet indicating sprinkler model and nozzles for each zone - include pressure, precipitation rate, flow, arc and radius total GPM ( spreadsheet form preferred) and the operating pressure at the worst case head ( with calculations shown) a good copy of the plan showing sprinkler placement with radius and arc at each sprinkler , piping, manifold, legend and north arrow. DO NOT INCLUDE THE CIRCLES YOU USED TO DETERMINE YOUR SPRINKLER SPACING. Include pipe sizing on your good copy by writing out the size beside the pipe, changing the colour and indicating this in your legend or changing the line pattern. Use correct symbols for heads, valves and piping. Make it neat and easy to read. ( The marking sheet is included at the end of this document. ) DESIGN PROCESS TURF 1. Layout Sprinklers Measure out lawn area and try to find a uniform distance or width of turfgrass area. For example if the lawn area is 8’ wide in many locations but is about 35’ wide at its widest area then the common denominator is 8’. Layout sprinklers using a compass. Start with the inside corners. There should be one sprinkler in each inside corner and one that sprays to the corner. Sprinklers can be in a random pattern (they do not have to be spaced in a triangular or square spacing) Attempt to get head to head coverage as much as possible. Sprinkler can vary in size For curved areas use smaller sprinklers. Only use variable arc sprinklers where necessary. When you have coverage across the whole turf area, select a sprinkler based on radius that is well suited to your site’s dimensions. You do not have to have all the same sprinkler radius. Choose a pressure that your sprinkler operates at. Do not change pressures ½ way through a zone. On your rough plan ( drawing with sprinkler circles) write down the arc, radius, gpm and precipitation rate at each sprinkler. 2. Layout zones Determine what size service line you have and where it is located. If you are accessing water via an outdoor tap, note the size of the supply line and test it for flow and pressure. Determine where the Point of Connection (POC) is located. ( to be discussed with the instructor) For this exercise you have 50 psi and 12 GPM at the source. Divide areas into hydrozones. Hydrozones are determined by environment( light, etc. and soil conditions) and plant material. If you have a shady area and a sunny area divide them into 2 hydrozones. Shrub beds will be on a different hydrozone than turf areas. In this exercise we only have turf. Make sure all the sprinklers in one hydrozone have matched precipitation rates. Matched precipitation rate is any sprinklers with precipitation rates within .25 in/hr of each other. YOU CANNOT mix heads with different precipitation rates within a zone. Do not mix rotors and spray heads. Do not mix rotators and fixed arcs. Add up the gpm of the sprinklers until you are close to the gpm at the source. DO NOT EXCEED the gpm at the source. That will be one hydrozone. 3. Piping Common pipe for residential irrigation lateral lines is PE (polyethylene)1404 75psi Draw in lines from the supply line or POC indicating where you would place the pipe linking sprinklers together within a zone. Use different colours for different zones and different line types for different sizes of pipe.( you can also label your pipe) Try to keep pipe lines from crossing driveways and other hard surfaces. Assume they are already installed. It is less expensive to run pipes all the way around a yard than through a driveway. If you have to put a pipe across a hard surface, indicate the installation of a sleeve. Try to keep pipe crossings in the lawn to a minimum. Run pipes along the edge of flower beds rather than through the lawn. Some crossing of the turf areas is essential and cannot be avoided, particularly with full circle heads in the lawn. Use proper pipe notations when lines cross one another. Use common trenches as much as possible. Determine the size of the pipe based on flow and a velocity not exceeding 5 feet per second. Use the following process for PE pipe Size pipe (using PE pipe) Starting at the end of the zone add up the gpm of each sprinkler until you get to 4 gpm ( this pipe will be ½” – see PE pipe chart) Continue adding up the gpm of the sprinklers until you get to 8 gpm ( this pipe will be ¾” – see PE pipe chart) if necessary continue adding up the rest of the heads to 12 gpm ( this pipe will be 1”) Calculate friction loss in the pipe. Determine the worst case head in each zone ( highest or furthest from the POC) Starting at the POC add up the gpm of the sprinklers in the 1” pipe. Using the friction loss charts determine the psi loss for 1” pipe with the determined gpm. Do the same thing for the ¾ “ section and the ½” section. Add the psi loss for each section together and subtract from the psi available at the POC. Determine psi loss through the valve and fittings. For fittings add an extra 10 %. Valve loss will be in the catalogs or subtract 2 extra psi. This is a simplistic way to determine if the last head has enough pressure to operate. MANIFOLD A 1” valve is standard. Anything smaller is a specialty item. Larger valves should only be used with larger pipe sizes. Determine 1. How many zones you will have 2. Which configuration would work best. 3. Where the best place for the manifold would be based on accessibility and distance from the source and power. Also take into consideration anything else you would include in the manifold such as pressure regulation or extra filtration. Draw in the manifold using valve symbol or ⧗ for each valve Subtract 2 psi for the valve from your final friction loss calculation. Design Assignment Marking SheetName: 1. a plan showing sprinkler layout and circles used to determine coverage /20 is there adequate head to head coverage over the entire area Are there wet or dry spots anywhere? Is there collateral damage from any area? 2. a sheet indicating sprinkler model and nozzles - include pressure precipitation rate, flow, arc and radius /10 Are sprinkler types indicated? Is arc, pressure precipitation rates, flow, and radius included? Are all friction loss calculations shown and correct? /10 3. a good copy of the plan showing sprinkler placement, piping, manifold, legend and north arrow. DO NOT INCLUDE THE CIRCLES YOU USED TO DETERMINE YOUR SPRINKLER SPACING. Include pipe sizing on your good copy by writing out the size beside the pipe, changing the colour and indicating this in your legend or changing the line pattern. Indicate arc and radius at each sprinkler head Piping Are all pipes sized and labeled correctly? /10 Are all pipes properly joined and shown correctly at crossings? Zones /5 Have zones been clearly defined and labeled has the number of zones been kept to a minimum Are all the zones valved Are the valves located correctly to minimize pipe installation? SprinklersAre arc and radius shown at each sprinkler head? /5 Good copy presentation /15 have all sprinklers, pipes, valves been drawn correctly (proper symbols)? Is there a legend? Is the drawing clean and easy to read? Total /75