Utah Division of Water Resources Institional Product Study

To evaluate the effectiveness of the Weather Reach WR-7 Receiver, two years of water use data-preceding installation was compared with three years following installation. This report presents the results for the 2000-2001 irrigation seasons (prior to installation) and the 2002-2004 irrigation seasons (after installation). The 2002 season represents only a partial year of data because the installations were made in the middle of the season. In addition to only being a partial year, many of the kinks in the management of the receivers were being worked out by the North Salt Lake Public Works personal.

Of the seven receivers installed in 7 different North Salt Lake City parks five were included in the analysis. The other two (one on part of the Main Park and the other on the North Parkway Park) did not have sufficient meter readings in years prior to installation to warrant the proper analysis. However all seven receivers have worked well and North Salt Lake Public Works personal have learned to use them effectively and are quite satisfied with there performance.

The irrigated areas of each park were measured using ariel photography and a measuring wheel. Meter readings were obtained monthly from the North Salt Lake Utilities Department. The Department usually reads meters on or around the 15th of every month during the irrigation season. For each park a target usage is calculated using the North Salt Lake Weather Station ET information and multiplying this by the area, assuming a irrigation efficiency of 70%and then converting that volume into gallons. This target is then compared to what was actually used to see how efficiently the parks are being irrigated. Thus this analysis takes the seasonal weather variability and the inefficiencies of the sprinkler system into account.

The following Table shows the information for the two irrigation seasons (2000-2001) prior to the installation of the WR-7 receivers.

Park Facility	Irrigated area(sf)	Target Useage(gal)	Actual Usage(gal)	Overwatering(%)
City Hall	54,000	2,591,000	3,528,000	136
Cottentree	27,000	1,296,000	2,538,000	196
Cottentree	46,000	2,060,000	2,070,000	100
South Parkway	75,000	3,599,000	3,844,000	107
Middle Parkway	56,000	2,687,000	2,682,000	100
Combined Facilities	258,000	12,381,000	14,662,000	118

As the table shows, overall the North Salt Lake Public Works Department has been fairly efficient in the irrigation of their park facilities – only over-watering (water application above the target amount) the facilities listed by 18% over the two seasons prior to the installation of the WR-7 receivers. They have been applying about 45 inches of water per year to the parks’ landscapes. This is in comparison to studies by the Division of Water Resources that indicate Utah homeowners, with automatic sprinkler systems, are generally applying about 50 inches of water per year to their landscapes.

After the installation of the WR-7 receivers the water use at each of the facilities were checked again. The following table shows the results for the three irrigation seasons after installation (2002-2004).

Park Facility	Irrigated area(sf)	Target Useage(gal)	Actual Usage(gal)	Overwatering(%)
City Hall	54,000	4,372,000	3,397,000	129
Cottontree	27,000	1,853,000	1,698,000	109
Mathis	46,000	2,140,000	2,701,000	79
South Parkway	75,000	4,322,000	4,718,000	92
Middle Parkway	56,000	3,144,000	3,522,000	89
Combined Facilities	258,000	15,831,000	16,228,000	98

As the data table shows, for the last three years of using the WR-7 receiver, the park facilities are now being watered at just under the target amount. They are now applying about 35inches of water to the park landscapes (down from 45inches). In comparing the two seasons prior to installation and the three seasons after installation North Salt Lake City has saved just over 2,000,000 gallons per year. At the current water rates the Public Works Department has saved nearly $2,600 per year. Also Public Works Department personnel are satisfied with the visual look of the turf-grass.

Another WR-7 receiver was installed at the Ballfields Park(adjacent to Hatch Park) in North Salt Lake. This park is watered with secondary (untreated) water bought by North Salt Lake City from Weber Basin Water Conservancy District. The following table compares the two irrigation seasons (2000-2001) prior to installation and the two seasons (2002-2003) after installation of the WR-7 receiver. The study did not include the 2004 season because the park underwent a massive construction project. The WR-7 receiver was not turned on during this project.

Irr. Season	Irrigated area(sf)	Target Usage(gal)	Actual Usage(gal)	Overwatering(%)
2000-2001	185,000	8,599,000	10,630,000	124
2002-2003	185,000	8,475,000	6,511,000	77

As can be seen by the data presented the water saved at this facility prior to installation and after is over 4,100,000 gallons in two years. This is untreated secondary water in which the city has purchased a contracted amount. This makes this saved water difficult to compute into dollars saved for the Public Works Department of North Salt Lake City. However, the water saved by more efficient usage could be used on other city owned facilities. It is interesting to note that even though the WR-7 receiver helped in the very efficient watering of this park facility (watering well below the target amount), Public Works Department personnel did not really see much difference visually in the turf-grass.

As a comparison, this study also wanted to analyze other park facilities that did not use the WR-7 receiver during both the 2000-2001 (prior to installation) seasons and the 2002-2004 (after installation) seasons. This was made difficult because most of North Salt Lake City’s park facilities with good meter records had been used as installation sites for the WR-7 receiver. However, one facility (Eaglewood Pump House) was found with reliable meter readings. The following table shows this facility’s data for each of the two time periods listed earlier in this study.

Irr. Season	Irrigated area(sf)	Target Usage(gal)	Actual Usage(gal)	Efficiency(%)
2000-2001	9668	464,000	844,000	182
2002-2004	9668	608,000	1,058,000	174

As the data shows, the Public Works Department of North Salt Lake has slightly reduced water use at this facility over the last three years vs. the prior two. The statewide water conservation media campaign and the drought response has caused many cities in Utah to begin implementing water conservation practices. However, as can be seen by the overall efficiencies presented in the table, it is still very difficult to efficiently water large irrigated areas. Even by rescheduling the automatic timer located at this facility, it is still being over-watered by 74% over the last three seasons.

Overall, North Salt Lake City has saved over 4 million gallons of water per year in both culinary and secondary usage at six of it’s facilities over the last three by using the WR-7 receiver to schedule irrigation on six of it’s park facilities.