Irrigation Assessment Report Mariana Glen Loveland, CO July 13, 2017

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1 2639 Spruce St Irrigation Assessment Report Mariana Glen Loveland, CO July 13, 2017 Executive Summary This report contains a summary and the results of an irrigation assessment performed at Mariana Glen HOA on July 13, Mark and Kylie with the Center for ReSource Conservation (CRC) performed the assessment through CRC s Slow the Flow Irrigation Assessment Program. The CRC is a non-profit organization that is putting conservation into action. The City of Loveland has partnered with CRC to offer this service to their customers in an effort to maximize irrigation efficiency and reduce water use. Page 1

2 Procedure We performed the following steps as part of the assessment: Met with Jim Schafer the HOA board member and Tom Sage the landscaper Visually inspected 51 of 54 zones of the property Performed 8 catch cup tests Performed 8 pressure tests Performed 8 soil and root depth tests Calculated a customized watering schedule for all zones tested Sprinkler Heads 101 There are two basic types of sprinkler heads: spray heads and rotor heads. Spray heads water in a fixed spray pattern when the system is turned on. Rotor heads water in a rotating pattern and are usually used to cover larger areas. Another type of sprinkler head that has become more common as a part of a high-efficient irrigation system is the rotary nozzle. These nozzles fit onto a tradition spray head while performing with the efficiency of a rotor head. Test Results and Findings We found the sprinkler system at Mariana Glen to be in fair condition, and we commend you for using a cycle and soak schedule on clock one. We had concerns about the number of broken heads, overspray, inappropriate arcs causing the overspray, inappropriate head types, and unusually high pressure in the spray zone we tested. We tested the distribution uniformity (DU), operating pressure, soil type, and root depth in 16 areas. We found an average DU of 47% and a range of 36% to 62% for all zones tested. We recommend correcting the system so that all zones perform with a DU value of at least 70%. A landscaping company can assist you in redesigning the location of the sprinkler heads to correct the DU. We found an average pressure of 48 PSI on the spray heads and 49 PSI on the rotor heads. The design pressure for spray heads ranges from 20 to 30 PSI; for rotor heads it ranges from 25 to 80 PSI. We recommend installing a pressure regulator in any spray zone with PSI above 30 to conserve water and prevent any unnecessary wear. We found that most of your soil is clay and that you have an average grass root depth of 4.8 inches. Distribution Uniformity Distribution Uniformity (DU) is a measure of how evenly a sprinkler system waters a given area. It is measured as a percentage. DU impacts the health and appearance of your turf. For example, if an area has a distribution uniformity of 50%, that means some parts of it are receiving half as much water as the rest of the area. If the watering schedule is set to give an appropriate amount of water to the areas with good coverage, the areas receiving less coverage will look poor. If the watering schedule is set to give an appropriate amount of water to the areas receiving the least water, the area as a whole will receive twice the amount of water it needs. We recommend a minimum distribution uniformity of 70% for all zones. Page 2

3 During the visual inspection and testing, we found the following problems on the sprinkler system: Leaking and broken lines, heads and nozzles Low and tilted heads Misting Overspray everywhere Blocked heads Heads with a 360 arc that should have a 180 arc Inappropriate heads for narrow strips of turf Based on the test results and our findings, we recommend that Mariana Glen take the following steps: Fix all the broken heads and lines to conserve water. This could take a considerable amount of man-hours, but it will save money in the long term. Adjust the arc on heads to reduce overspray, misting, and blockage. This might require replacing nozzles to match precipitation and are easy fixes that do not require a lot of work. Schedule In the body of the report, we have provided watering schedules for zones on which we performed catch cup tests. We base our watering schedules on evapotranspiration (ET), the amount of water the grass and soil lose to evaporation and transpiration each year. We use a historical average ET of 27 inches per watering season to determine our schedules. In general, we found that the current watering schedule is somewhat higher than we would expect for spray zones and is lower than our recommendations for rotor zones. We recommend using a cycle-and-soak schedule for both clocks and limiting watering days to three days per week currently. To avoid encouraging over-watering, we did not supply an irrigation schedule for zones with a distribution uniformity of less than 40%. Different Times for Spray and Rotor Zones Spray and rotor heads emit water at different rates and usually need to be programmed to water for different amounts of time. Spray zones usually need to be watered for approximately 60% of the length of time required for rotor zones. Conclusion Thank you for your participation in the Slow the Flow Outdoor Irrigation Assessment program. We hope that the data and recommendations in this report will help you maintain a beautiful landscape while using water as efficiently as possible. If you have any questions, please feel free to contact our Program Manager at Mark and Kylie Slow the Flow Technicians Center for ReSource Conservation Page 3

4 Full Report Table of Contents I. Assessment Procedure 4 II. Site Description 4 III. Findings 5-13 a. Issues Needing Immediate Attention 5 b. General Findings 5-6 c. Problems Found 7-9 d. Visual Inspection Notes e. Test Results 13 IV. Schedules Assessment Procedure Upon arrival at Mariana Glen HOA, we met briefly with board member Jim Schafer responsible for managing the property and landscaper Tom Sage responsible for maintaining the property. After meeting with Jim and Tom, we performed the following steps of an assessment: Visual inspection: We inspected all sprinkler heads within 51 zones on the property. During the visual inspection, we observed the zones as they operated, looked for problems, and recorded what we observed. Catch cup tests: We chose 8 areas on the property to perform catch cup tests. For each test, we laid out a set of catch-cups in a grid pattern on the turf and recorded the amount of water that fell in each cup during a specified period of time. This gave us a measurement of how evenly the sprinkler system waters in each area, called distribution uniformity, and a measure of how quickly the system waters, called precipitation rate. Pressure tests: We measured the operating pressure of the sprinkler system in each area where we performed catch cup tests. We compared the observed pressure to the recommended operating pressure for each head type. Soil and root depth tests: We took a soil sample in each test zone to determine soil type and root depth of the grass. Determine a customized watering schedule: We used the precipitation rate and the soil type in each tested zone to determine a customized watering schedule for that zone. These watering schedules are included in this report. Written report: After leaving the site, we wrote this report of our results. Site Description Mariana Glen is an HOA located in Loveland CO which irrigates turf, shrubs, and flowerbeds. There are two control clocks that we designated 1 and 2 for the purposes of this report. Clock 1 is a Hunter I-Core located at the corner of Marcy and Tacanecy that currently waters turf, shrubs, and flowers once at night four days a week. Clock 2 is a Hunter I-Core located just north of Tacanecy off the path before the first large open park area. It currently waters turf and shrubs three times in the morning every day of the week. Both clocks have run times approximately minutes. Page 4

5 Findings Issues Needing Immediate Attention We found the following issues needing immediate attention. Clock 1 at the corner of Marcy and Tacanecy: Zone 16: broken head Zone 21: two broken heads Zone 22: broken head and a broken line Clock 2 just north of Tacanecy off the path before the first large open park area: Zone 12: broken head at the road Zone 18: broken line General Findings Spray Distribution Uniformity Precipitation Rate Root Depth (inches) Zones (%) (in./hour) Average Range Rotor Distribution Uniformity Precipitation Rate Root Depth (inches) Zones (%) (in./hour) Average Range We recommend that the irrigation system be corrected to perform at a minimum 70% distribution uniformity for all zones. To avoid overwatering, we did not supply an irrigation schedule for zones with a distribution uniformity of less than 40%. We found grass root depths of 2 to 6 inches, which are lower than our recommended 6 to 12 inch range. We encourage deep roots as they help grass resist disease and drought. We found soil types of clay and used the soil type and precipitation rate found in each zone to determine a customized watering schedule for that zone. Page 5

6 Rotor Pressure Spray Pressure (PSI) (PSI) Average Range Depending on the brand and model, the design pressure for rotor heads ranges from 25 to 80 PSI. The design pressure for spray heads ranges from 20 to 30 PSI. One clock is using a cycle and soak schedule, which is what we recommend for both clocks. The problems observed at Mariana Glen are summarized next. Page 6

7 Problems Found Leaks Clock 1 at the corner of Marcy and Tacanecy: Zone 16: broken head Zone 21: two broken heads Zone 22: broken head and a broken line Clock 2 just north of Tacanecy off the path before the first large open park area: Zone 12: broken head at the road Zone 18: broken line Incorrect Pressure The pressure is too high on some of the zones causing them to mist, which is inefficient because the water can easily blow away or evaporate. As a result, the affected zone must be watered for a longer period of time because a large portion of the water emitted does not actually reach the turf. Moreover, when sprinkler heads operate at pressures that exceed their design parameters, they will wear out prematurely. Pressure reducers should be installed on zones in which the pressure is too high. Clock 1 at the corner of Marcy and Tacanecy: Zones 21 and 22: high pressure for spray heads (48 PSI) Misaligned, Clogged, Blocked, Sunken, and Tilted Heads Many of the heads were misaligned, clogged, blocked, sunken, and/or tilted. Over time, heads tend to sink and tilt due to the natural settling of the earth and wear-and-tear from foot traffic and lawn maintenance. Although they are still operational, these heads often do not spray water onto the turf or spray in undesirable patterns. These seemingly minor issues have the potential to greatly reduce the efficiency of the system, resulting in overspray, brown spots, misting, and wasted water. These problems are relatively easy and inexpensive to fix, and correcting them can dramatically increase the system s efficiency. Raise and level all heads to the ground surface and unclog or unblock affected heads. The spray from each head should be able to clear the grass when it is at its tallest. Clock 1 at the corner of Marcy and Tacanecy: Zone 1: 2 heads blocked by tree Zone 3: tilted head Zone 6: tilted head Zone 8: low heads Zone 10: 2 heads blocked by tree Zone 16: low head, head blocked by tree Zone 22: 2 tilted heads, 2 clogged heads Zone 26: head spraying into ground, low head Page 7

8 Page Spruce St Clock 2 just north of Tacanecy off the path before the first large open park area: Zone 1: tilted head Zone 2: tilted head Zone 3: low head Zone 5: tilted head, trajectory spraying tree Zone 8: blocked head Zone 9: low head Zone 13: low head Zone 17: tilted head Zone 23: tilted head Zone 24: low and tilted head Zone 25: tilted head Zone 26: low head Mixed Zones Design specifications (radius, throw pattern, operating pressure, and precipitation rates) for sprinkler heads are specific to the brand, type and model. Therefore, different brands and models of heads should not be placed on the same zone because it will create inefficient watering. In some areas, fixed spray heads, rotor heads, and/or high-efficiency rotary nozzles were located on the same zone. Fixed spray heads are designed to emit an average of 50% more water than rotor heads. High-efficiency rotary nozzles are designed to emit an average of 50% less than rotor heads. Since watering times can only be controlled zone by zone and not by individual heads, the areas watered by sprays will receive an average of 50% more water than the areas watered by rotors and rotary nozzles 50% less than rotor heads. Moreover, the optimal operating pressure for sprays and rotors are very different. Fixed spray heads are designed to operate between 20 and 30 PSI, rotors operate best between 40 and 80+ PSI, and rotary nozzles around 40 PSI. Therefore, if the watering time and pressure are correct for one type of head, they will be wrong for the other type of head. For these reasons, sprays, rotors, and/or highefficiency rotary heads should never be located on the same zone. Make sure all heads within a zone are as uniform as possible. If a head needs to be replaced, replace it with a head that matches the other heads on the zone. Clock 2 just north of Tacanecy off the path before the first large open park area: Zone 23: rotors and HE nozzles Poor Head Spacing Many of the zones had heads that were spaced too far apart to achieve head-to-head coverage, creating brown spots. Head-to-head coverage is achieved when the spray from each head reaches to the next head and vise versa. Head spacing and/or throw radius should be adjusted to achieve head-to-head coverage. Clock 1 at the corner of Marcy and Tacanecy: Zone 14

9 Overspray Some of the heads on the property were spraying onto sidewalks and other hardscapes. To avoid overspray, heads should be placed several inches away from the edge of the landscape. To reduce the throw radius of a sprinkler head up to 20%, the radius adjustment screw should be utilized. If the radius needs to be reduced more than 20%, a nozzle with a shorter throw radius should be installed. The overspray on clock 1 is mostly due to inappropriate head types watering the strip between the road and sidewalk which include zones 3, 4, 12 and 13. Zones 23 and 24 on clock 1 have overspray onto roads and sidewalks. This is a general problem on the majority of zones on clock 2, but specific zones we noted are 11, 12, 13, and 19. Incorrect Spray Patterns Many of the heads had incorrect arcs. The arc of a sprinkler head is the degree of a circle the spray covers. Sprinklers may spray in quarter circles, half circles, two-thirds circles, full circles, or the arc may be adjustable. When the arc is too wide, it can lead to overspray onto undesired areas. Conversely, if the arc is too narrow, it can lead to dry spots and poor coverage. Incorrect spray patterns can usually be corrected with a few minor adjustments to the sprinkler heads. For hard-to-cover areas (such as curves or odd angles) that are watered by spray heads, we recommend using a Variable Arc Nozzle (VAN) that allows a custom arc to be set. Zone 8 on clock 2 and zones 1, 10, 16, and 21 on clock 1 have heads that are spraying into trees and could have the arcs adjusted to conserve water. Zones 2, 3, 4, 18, and 19 on clock 2 have heads that spray in a 360 where 180 would be more appropriate. Check Valves After the system was turned off, water continued to run out of the heads located at the lower end of the zone. This was because the water left in the system was draining. It is possible to prevent this by installing heads that have check valves. Check valves seal off the sprinkler heads when the zone is shut off, keeping water in the pipes. Check valves not only eliminate the loss of water from the system, but also prevent excess wear on the system s pipes. Most sprinkler heads can be retrofitted with check valves. The zones at the Tacanecy dr. entrance need check valves. Page 9

10 Visual Inspection Notes Clock 1: Hunter I-Core at the corner of Marcy and Tacanecy Zone Number Type (Spray, Rotor, High-Efficiency Nozzle, Drip) 1 R Misting, 2 blocked by tree 3 R Overspray Inspection Notes 4 R Tilted, overspray, inappropriate heads for narrow strip 5 R 6 R Tilted 7 R 8 R Mostly low 10 R 2 blocked by tree 11 R 12 R Inappropriate heads for narrow strip 13 R Inappropriate heads for narrow strip, misting 14 R Poor head to head spacing 15 R 2 under tree 16 R Low, blocked by tree, broken head 17 R 18? 19 S 20 S 2 under tree 21 S 2 watering tree, 2 broken heads 22 S 2 tilted, 1 broken, 2 clogged, broken line 23 R Overspray Page 10

11 24 R Overspray 25 R 26 R Spraying into ground, low 30? 31? Clock 2: Hunter I-Core just north of Tacanecy off the path before the first large park area. Zone Number Type (Spray, Rotor, High-Efficiency Nozzle, Drip) 1 R Tilted, misting Inspection Notes 2 R Tilted, inappropriate arc at sidewalk, 360 arc instead of R Low, misting, 360 arc instead of R 360 arc instead of R Tilted, trajectory spraying tree 6 R 7 R 8 R Blocked 9 R Low 10 R 11 R Overspray 12 R Overspray, broken head at road 13 R Overspray, low 14 R 15 R 16 R Page 11

12 17 R Tilted 18 R 360 arc instead of 180, broken line 19 R 360 arc instead of 180, misting, overspray 20 R 22 R 23 Mixed Tilted, mixed HE heads 24 R Low and tilted 25 R Tilted 26 R Low 27 R 28 R 29 R Page 12

13 Test Results Catch Cup Test Clock ID Zone Number 3,7,11 15,16,17 21,22 3,5 4 1,8 Head Type Rotor Rotor Spray Rotor Rotor Rotor Head Pressure (psi) PR (inches/hr) DU (%) Root Depth (inches) Soil Type Clay Clay Clay Clay Clay Clay Catch Cup Test 7 8 Clock ID 2 2 Zone Number 9 11,12 Head Type Rotor Rotor Head Pressure (psi) PR (inches/hr) DU (%) Root Depth (inches) 3 6 Soil Type Clay Clay Page 13

14 Schedules We base our watering schedule on evapotranspiration (ET). ET is the amount of water the plants and soil lose to evaporation and transpiration each year. It is the amount of water a plant needs to survive. We base our recommended schedule on an average historical ET rate for bluegrass in the Denver area, which is 27 inches per year. Our schedules are designed to put this amount of water back into the landscape during the watering season. Please keep in mind that 27 inches per year is a historical average; if the weather is significantly hotter and drier or cooler and wetter than average, you may need to adjust your watering schedule. Cycle and Soak in short cycles, or cycling, is important if your landscape has heavy clay soils, significant slopes, or if your sprinklers have a high precipitation rate. For most systems, we suggest dividing watering times into two or three cycles with roughly one hour between each cycle. This gives the soil time to absorb the water applied during one cycle before the next begins. Cycling helps prevent runoff and gives your turf a deeper watering, which encourages deeper root growth. On most control clocks, the multiple start times feature can be used to implement a cycle-and-soak schedule. Schedule We recommend using this watering schedule as a GUIDE during non-restrictive years. We have provided schedules for zones on which we performed catch cup tests. You may use these schedules as a base for watering other zones that have similar precipitation rates (those with the same head type and a similar design). We recommend adjusting this schedule to account for varying environmental factors, such as sun exposure, in different zones. We do not recommend drastically changing watering times in a short period of time. This will stress the turf significantly. If our recommended watering schedules are significantly different than the current watering schedule, we suggest slowly reducing the current watering time to ease the turf into the new schedule. Page 14

15 Schedules Clock: 1 Zone: 3 Zone Type: Rotor Current minutes/week: 294 Clock: 1 Zone: 7 Zone Type: Rotor Current minutes/week: 252 Clock: 1 Zone: 11 Zone Type: Rotor Current minutes/week: 168 Page 15

16 Clock: 1 Zone: 15 Zone Type: Rotor Current minutes/week: 336 Clock: 1 Zone: 16 Zone Type: Rotor Current minutes/week: 210 Clock: 1 Zone: 17 Zone Type: Rotor Current minutes/week: 294 Page 16

17 Clock: 1 Zone: 21 Zone Type: Spray Current minutes/week: 126 May 1 3 June-August 2 3 September 1 3 minutes/week: See below We did not provide a recommended watering schedule for this zone because the distribution uniformity was below 40%. When the distribution uniformity is below 40%, certain areas of the zone would need to be over-watered in order for other areas of the zone to receive enough water to remain healthy. Thus, providing a watering schedule for this zone would encourage over-watering. Please refer to the list of problems found during the visual inspection for this zone to find ways to improve the distribution uniformity and make this zone more efficient. Clock: 1 Zone: 22 Zone Type: Spray Current minutes/week: 126 May 1 3 June-August 2 3 September 1 3 minutes/week: See below We did not provide a recommended watering schedule for this zone because the distribution uniformity was below 40%. When the distribution uniformity is below 40%, certain areas of the zone would need to be over-watered in order for other areas of the zone to receive enough water to remain healthy. Thus, providing a watering schedule for this zone would encourage over-watering. Please refer to the list of problems found during the visual inspection for this zone to find ways to improve the distribution uniformity and make this zone more efficient. Page 17

18 Clock: 2 Zone: 1 Zone Type: Rotor Current minutes/week: 50 Clock: 2 Zone: 3 Zone Type: Rotor Current minutes/week: 70 minutes/week: 200 May June-August September Clock: 2 Zone: 4 Zone Type: Rotor Current minutes/week: 50 minutes/week: 84 May June-August September Page 18

19 Clock: 2 Zone: 5 Zone Type: Rotor Current minutes/week: 40 minutes/week: 200 May June-August September Clock: 2 Zone: 8 Zone Type: Rotor Current minutes/week: 80 Clock: 2 Zone: 9 Zone Type: Rotor Current minutes/week: 80 Page 19

20 Clock: 2 Zone: 11 Zone Type: Rotor Current minutes/week: 60 Clock: 2 Zone: 12 Zone Type: Rotor Current minutes/week: 40 Please contact us if you have any questions regarding the information in this report. Thank you for helping to conserve Colorado s fresh water! Sincerely, The Center for ReSource Conservation Slow the Flow Water Conservation Team 2639 Spruce Street water@conservationcenter.org Page 20