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The effectiveness of water irrigation policies for residential turfgrass
Land Use Policy 31 (2013) 378–384
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The effectiveness of water irrigation policies for residential turfgrass Lin A. Ozan, Kamal A. Alsharif ∗ Department of Geography, Environment, and Planning, 4202 East Fowler Avenue, NES 107, University of South Florida, Tampa, FL 33620, United States
a r t i c l e
i n f o
Article history: Received 16 February 2012 Received in revised form 31 July 2012 Accepted 1 August 2012 Keywords: Turfgrass Domestic water policy Restrictions Citations Lawns
a b s t r a c t Turfgrass irrigation policies have been implemented in various regions of the U.S. to reduce domestic water consumption. Mandatory restrictions are often enforced by issuing citations to violators with the intent to promote compliance and deter violations. This study provides a detailed investigation of past water restrictions and compliance, and attempts to determine which factors are related to high rates of water usage within communities of Tampa, FL. The adjusted rainfall rate had the most significant relationship with water usage in the communities under study. Water usage increased in each examined community after it transitioned to more stringent water usage restrictions, with cited restriction violators increasing usage to a greater extent than their uncited counterparts. This increase may primarily be attributed to conflicts between the local water consumption policy and binding homeowner association rules. When the once-a-week usage restriction was in place, the area faced drought conditions. Therefore, homeowners irrigated more to meet the water needs of their lawns despite the restrictions imposed on them by their local government. © 2012 Elsevier Ltd. All rights reserved.
Introduction An enormous amount of water is being used on turfgrass in many situations where water is limited or even scarce. For example, in the arid region of the American West, lawn irrigation by one measure exceeds 50% of domestic water usage (Mayer et al., 1999). Lawn irrigation represents the largest portion of domestic water usage across the U.S. (Mayer et al., 1999). In addition, lawn irrigation accounts for at least half of all water consumed by the domestic sector in most Australian capital cities (Brennan et al., 2007). Furthermore, automated systems typically do not distribute water uniformly to appropriately irrigate turf landscapes, and they have many inherent inefficiencies that increase water loss (Haley et al., 2010). Therefore, restricting outdoor water usage provides an excellent opportunity to mitigate domestic usage. Kenney et al. (2004) examined data from regions with mandatory and voluntary water restrictions that primarily focused on limiting residential lawn watering during a prolonged Colorado drought. They found that mandatory restrictions resulted in more limited water use than voluntary restrictions, even when accounting for climatic variation across the studied areas. Water restrictions can be useful for mitigating domestic water usage, but a restrictive policy is only as effective as the enforcement mechanism. Extensive research is crucial to determine if whether current
∗ Corresponding author. Tel.: +1 813 974 4883; fax: +1 813 974 4808. E-mail addresses: [email protected] (L.A. Ozan), [email protected] (K.A. Alsharif). 0264-8377/$ – see front matter © 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.landusepol.2012.08.001
restrictions should be maintained or restructured to further mitigate domestic water usage. The policies examined do not consider the amount of water required to sustain a healthy lawn but instead are designed to conserve water and only maintain the population’s essential water requirements. St. Augustine and Bermuda grass, the grass species typically recommended by deed-restricted communities in Florida suburbs (Trenholm et al., 1991) require two or three scheduled irrigations a week to maintain acceptable quality during the summer months (Trenholm et al., 2002). Tampa’s policies have historically alternated between prolonged periods of restricting irrigation to watering either once or twice a week; this requirement creates a dilemma for homeowners who are required by their binding community rules to maintain healthy turfgrass. To better understand the compatibility of local policy and binding community directives, this study determined residential water use patterns and magnitudes within deed-restricted communities and mapped enforcement mechanisms using high-resolution geographic information system (GIS) analysis and other strategic mapping methods at the community level. Specifically, this study (1) developed GIS data sets that were used to quantitatively map water usage at the parcel level; (2) examined the relationship between domestic water usage and key environmental and recreational factors, such as rainfall, seasonality, and the presence of swimming pools; and (3) mapped the enforcement of residential lawn irrigation policy non-compliance to determine spatial relationships within and between the communities and to test the effectiveness of current enforcement practices. This study focused on three deed-restricted communities located in northern Tampa, FL. An in-depth investigation into domestic water usage in such
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Table 1 Irrigation restrictions enacted during different time periods in the City of Tampa. City ordinance 2000-69
City ordinance 2003-316
City ordinance 2006-104
March 16th 2000 to November 24th 2003 Addresses ending with an even number or letters A through M, only on Tuesdays
November 25th 2003 to May 4th 2006 Addresses ending with an even number or letters A through M, only on Tuesdays and Saturdays Addresses ending with an odd number or letters N through Z, only on Sunday and Wednesday Irrigation of properties was prohibited from 8:00 a.m. to 6:00 p.m. on permitted days Irrigation prohibited at all times on Monday, Thursday, and Friday
May 5th 2006 to December of 2010 Addresses ending with an even number or letters A through M, only on Tuesdays
Addresses ending with an odd number or letters N through Z, only on Sundays Irrigation of properties was prohibited from 8:00 a.m. to 6:00 p.m. on permitted days Irrigation prohibited at all times on Monday, Wednesday, Thursday, Friday, and Saturday
communities would ultimately help environmental managers to effectively enact and enforce policies that are aimed at protecting our most precious resource. Cultural perspectives on the lawn The current ideal of the monoculture lawn can be traced to the landscapes constructed by privileged French and British individuals in the 16th and 17th centuries and is a variation on their scale and structure (Feagan and Ripmeester, 2001). It has also been tied to statesmen such as Andrew Jackson Downing and Thomas Jefferson, who envisioned the landscape as being intertwined with the progress of democracy, liberty, and moral health (Feagan and Ripmeester, 2001). Downing held that people’s pride in their country was tied to pride in their homes, and to show patriotism and pride, they must tend to their homes appropriately. This ideology was perpetuated throughout the formation and industrialization of the United States. Currently, a lawn is no longer an elitist means of displaying patriotism. Americans have become more affluent and have expanded their personal landholdings to the suburbs, which have promoted the expansion of the lawn (Robbins and Birkenholtz, 2003). The post-World War II era of nationalism, identity, and community led to shifts in work and leisure activities. The lawn has become associated with private enterprise and personal property. It has grown beyond its physical presence to become a symbol of public order. A well-maintained lawn is an essential element in developing an appropriate social and moral order (Feagan and Ripmeester, 2001). The commodification of the lawn and the esthetics associated with it are now a reflection of purity, cleanliness, and decency within the American suburb (Feagan and Ripmeester, 2001). Researchers suggest that the aspiration to maintain one’s yard may be motivated in part by the desire for neighborhood solidity and/or conflict avoidance (Hirsch and Baxter, 2009). In addition, residents may perceive conformity with water restrictions as a sign of neighborhood degradation, and they therefore are encouraged to avoid conflicts with neighbors by maintaining yard care standards (Hirsch and Baxter, 2009). Arguably, the lawn’s greatest role in the social process is ideological; it supports a set of concepts and norms regarding the way a society should be organized (Feagan and Ripmeester, 2001). In addition to the aspiration for community solidarity, many homeowners are obligated to follow the directives of their homeowner associations. In Florida, many homeowner associations have adapted their own lawn policies. For example, Hunter’s Green Community Association, a community included in this study, permits only St. Augustine turfgrass; it also mandates that irrigation systems must cover 100% of the lawn; and that watering must comply with local and state policies (Hunter’s Green Community Association Inc., 2012). On the other hand, the West Meadows
Addresses ending with an odd number or letters N through Z, only on Sundays Irrigation of properties was prohibited from 8:00 a.m. to 6:00 p.m. on permitted days Irrigation prohibited at all times on Monday, Wednesday, Thursday, Friday, and Saturday
Community Association permits St. Augustine, Bahia, Bermuda, and Zoysia grass, and holds the homeowner responsible for maintaining a healthy and acceptable lawn (West Meadows Property Owners Association Inc., 2012). Thus, the homeowners must have the knowledge necessary to meet their community associations’ policies and healthy lawn requirements. Noncompliance due to a lack of knowledge is not considered an excuse. In addition, some of the language in the homeowners’ manuals is open to interpretation. For example, how does the West Meadows Homeowners Association define a healthy and acceptable lawn? Is lawn health a matter of the individual homeowner’s subjective interpretation or are there criteria specified in a document? Tampa’s historical local irrigation policy The water demanded by Tampa citizens has periodically exceeded availability over the past few decades; in these instances, water was purchased from suppliers to meet demand. Contributing factors include inadequate rainfall, escalating irrigation demands, and decreased flows into the Hillsborough River (Water Restrictions, 2009). In addition, the decreased flows into the Hillsborough River have caused Tampa’s reservoir levels to decline more rapidly and recover more slowly than in past years. Tampa’s reservoir provides 90% of the treated water distributed to Tampa Water Department customers and is the primary source of drinking water for the city. To conserve water resources, water usage restrictions have been enacted to help ensure a sufficient quantity of indoor water for the Tampa community (City of Tampa, 2009). The City of Tampa’s outdoor water use restrictions are in effect for all residents within the incorporated city limits and for residents outside the incorporated city limits to the extent permitted by law. However, hand watering of new and existing lawns was not restricted. For the past decade, Tampa’s water restrictions have oscillated between once a week and twice a week automated lawn irrigation to curb demand and preserve water resources. The irrigation restrictions were enacted at different times and covered different time periods (Table 1). As Table 1 shows, the restrictions controlled the days and times that homeowners could irrigate their lawns. In addition, both once and twice a week policies were used. More stringent policies were in effect in Tampa during the Spring of 2009. This policy restricted lawn irrigation to hand watering only. This common water restriction is usually implemented to completely ban the use of automated, in-ground sprinkler systems and permits households to substitute for it with labor-intensive hand-held watering (Brennan et al., 2007). Policy effectiveness There are four primary types of domestic water conservation and mitigation strategies used in the United States: rationing
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(Nelson, 1979; Mercer and Morgan, 1989; Lund, 1995), usage restrictions (Mayer et al., 1999; Kenney et al., 2004; Brennan et al., 2007), pricing (Dandy, 1992; Timmins, 2003; Brennan et al., 2007; Grafton and Ward, 2008), and technology (Renwick and Archibald, 1998; Pereira et al., 2002; Haley et al., 2007; McCready et al., 2009). There is a difference between rationing and usage restrictions. Rationing traditionally reduces the amount used through fixed allotments, percentage reductions, and conservation credits (Lund, 1995; Nelson, 1979). However, a usage restriction bans the use of water for irrigation outside of certain days or times. The four primary types of domestic water conservation strategies are not mutually exclusive, and hybridized versions incorporate elements of multiple strategies. The literature does not arrive at a clear consensus as to which stand-alone strategy is the most effective. This lack of consensus is due to the multitude of different variables within each specific study area. One of the most crucial steps in the policy cycle is the evaluation of policy. Measuring the effectiveness of a policy is paramount in determining whether the policy should remain as is, or be modified to produce better results. The key criteria for policy evaluation include validity, importance, usefulness, originality, and feasibility (Nagel, 1990). The City of Tampa’s policies mentioned above were formulated to eliminate unessential domestic water usage. Unessential usage reflects what the City of Tampa deems unnecessary and includes domestic irrigation. However, some homeowners consider irrigating their turfgrass to be an important component of their water usage. Nevertheless, such a policy is valid when the availability of water for essential human requirements is compromised. Drought conditions in the region have threatened Florida’s water security, and water conservation policies are of grave importance. However, without an around-the-clock enforcement mechanism coupled with citizen adherence, local government policies cannot be feasibly enforced. This study sought to determine the effectiveness of the aforementioned restrictions. Study area Tampa is located midway along the west coast of Florida and serves as the administrative center for Hillsborough County. Its incorporated boundaries total 170.6 square miles, which include 112.1 square miles of land and 58.5 square miles of water (Hillsborough County, 2010). Tampa’s current population is 335,709, a 10.6% increase from the 2000 United States Census figure (U.S. Census Bureau, 2011). The study area comprises key communities within the City of Tampa’s zip code (33647) that are bounded by Interstate 75 to the south and west, Morris Bridge Road to the east, and County Line Road to the north (Fig. 1). The communities are West Meadows, Hunter’s Green, and Arbor Greene. According to the Southwest Florida Water Management District (SWFWMD) (2009), Tampa, was under a phase III extreme water shortage alert during thirty of the sixty months examined in this study. However, the data analysis covered only 48 months, from June 2004 to May 2008, to obtain an equal number of months for twice and once a week irrigation restrictions. SWFWMD analyses of drought indicators (rainfall, groundwater levels, and stream flows) characterize conditions as normal or one of four degrees of abnormality. These four degrees are moderate, severe, extreme, and critical, and they are based on a comparison with historical data (SWFWMD, 2009). Increased ambient air temperature, in conjunction with decreased precipitation rates and increasing water usage, has in the past driven the city into the critical category and can potentially do so in the future. Throughout the last decade, Tampa has experienced varying degrees of abnormality. In response, the City of Tampa adopted water restriction policies based on SWFWMD recommendations, with the water authority overseeing compliance. The city
Fig. 1. Map of Tampa, Florida zip code 33647.
adopted specific policies to curtail domestic water usage within the city’s incorporated boundaries during the forty-eight-month study period. The area with the highest incidence of enforced irrigation violations is zip code 33647. Conventional wisdom would dictate that this zip code would be the perfect area to determine whether the enforcement of and adherence to the city’s watering restrictions are effective at reducing domestic water usage, because of the noncompliance citations. The three communities of West Meadows, Hunter’s Green, and Arbor Greene have been hotspots for cited water use violations in the past decade. The residents of these deed-restricted communities are placed in a difficult position. These single-family homeowners are required by the City of Tampa to limit lawn irrigation and by their binding community rules to maintain a healthy green lawn. The residents must choose either to adhere to Tampa’s restrictions or homeowner association’s requirements to avoid a monetary penalty, or devise inventive irrigation methods that avoid community and legislative backlash. Methods The data set summarizes water usage by month during once a week and twice a week restrictive periods. The water usage data were obtained from Tampa Bay Water, and they include water usage by month for individual addresses throughout the City of Tampa. The data were acquired from Tampa Bay Water’s GOVNET program. Indoor water use was assumed to be constant over the course of the year. Thus, seasonal and inter-annual variations were most likely due to outdoor water use. In June 2007, Tampa Bay Water began to develop a high-resolution water distribution application for analyzing water usage obtained from archival and current billing records. The ensuing application was named GOVNET and was used to manage all future water conservation efforts. The data reside in Tampa Bay Water’s enterprise GIS, which incorporates a multi-terabyte ArcSDE geo-database server and numerous non-spatial SQL servers to accumulate differing water quality, consumption, SCADA, and wetland data (ESRI, 2008). The data comprise
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time-series billing data from all member governments: Hillsborough County, Pasco County, Pinellas County, City of New Port Richey, City of St. Petersburg, and the City of Tampa. All data were recorded on a monthly basis from 1998 to the present for over 500,000 individual water use accounts and were geo-coded to a physical parcel (ESRI, 2008). This source was used to create a data set that was useful for the present analysis. The selection of the study areas was strategic, in that the areas had to meet three specific criteria to be included in the study. First, the areas could not have reclaimed water available to use for irrigation. If the areas had reclaimed water available, domestic usage would potentially be highly skewed and non-representative. Second, major construction of the community within the neighborhoods to be examined must have begun the last twenty years, and the individual homes examined must have been built before 2003. This criterion ensured that the homes examined were equipped with automated in-ground irrigation systems and that individual homes had existing lawns before the study began. Third, the communities examined were required to be cited violation hotspots. This criterion ensured that the results of the study accurately depict the effectiveness of the restrictive policies. After all specified qualifications for community selection were met, a kernel density analysis using the Getis-ord Gi function was conducted within zip code 33647 to determine which communities or neighborhoods had clusters of cited violations. A base map was created using GIS data from the Hillsborough County Property Appraiser’s February 2010 assessment. Only parcels with single-family homes built before 2003 were used for the map. Within this landscape, research focus areas were selected. Sampling was used due to the large volume of data that would otherwise be individually recorded for each month for each parcel. The three hotspot communities of West Meadows, Hunter’s Green, and Arbor Greene were chosen due to high incidences of cited water restriction violations and the availability of water usage data. Each parcel with an associated single-family home built before 2003 in each of these communities was systematically numbered for quick reference. Two hundred twenty-five homes within the specified communities (49 in West Meadows, 112 in Hunter’s Green, and 64 in Arbor Greene) were chosen by random number generation software, representing approximately 10% of the homes built before 2003 within the three communities. The 225 sampled homes provide for a 6.31% margin of error at a 95% confidence level from the total population of 3203 single-family homes. The address of each selected home was used to query the GOVNET database. The water usage data were extracted from the database for the sampled households for the duration of the study. To construct the GIS data set, the following attributes were recorded for each of the selected homes: address (ADDRESS), the parcel’s square footage (PSQFT), the presence or absence of a pool (POOL), citation dates (CITATION1, CITAION2, and CITATION3), neighborhood name (NEIGHBORHOOD) and monthly water usage from December 2003 through November 2008. The duration of the study was chosen by selecting equal intervals of once a week and twice a week watering restrictions, beginning and ending with the same month. Twice a week irrigation restrictions went into effect on November 25, 2003, and were replaced by once a week irrigation restrictions on May 5, 2006. Therefore, data from June 2004 through May 2008 were employed, for a total of 48 months. This data set encompassed 24 months of twice a week watering restrictions (June 2004–May 2006) and 24 months of once a week watering restrictions (June 2006–May 2008). The individual months were then grouped into wet, moderate, and dry seasons based on local rainfall data and historical pan evaporation rates. The rainfall data were collected from a weather data collector maintained by the USGS, located approximately 8 miles from the study area. The rainfall data were then adjusted by historical
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evapotranspiration rates, determined by NOAA for the Tampa metropolitan statistical area, to establish grouped seasons based on actual data. The wet season includes the months of June, July, August, and September. The moderate season includes the months of October, November, December, and January. The dry season includes the months of February, March, April, and May. The average monthly water usage of homes with pools and homes without pools were calculated to determine whether there was a significant relationship between water usage and pool ownership. Next, domestic water usage was tested for any relationship with rainfall patterns. This was accomplished by obtaining the overall monthly average water usage from June 2004 to May 2006 (twice a week irrigation restrictions) and comparing it to the overall monthly average water usage through June of 2006 to May of 2008 (once a week irrigation restrictions). The Pearson’s r correlation coefficient was calculated using monthly rainfall totals and monthly water usage totals for each of the two periods. The correlation coefficient was calculated for the study area as a whole and for each individual community during both periods to determine which community, if any, had the greatest water usage in the area. The correlation coefficients were tested for significance by determining the critical value at a 0.05 confidence interval. The fourth step of the research detailed the relationship between seasonality and water usage. This step was accomplished by dividing the data into months of wet, moderate, and dry conditions based on monthly rainfall and local evapotranspiration rates. Next, a comparative analysis was initiated by obtaining the overall monthly average water usage within each season from June 2004 to May 2006 (twice a week irrigation restrictions) and comparing it to the overall monthly average water usage within each season from June 2006 to May 2008 (once a week irrigation restrictions). The percent change in water usage from twice a week irrigation restrictions to once a week irrigation restrictions was calculated to determine whether water usage changed with the modification of restrictions. Statistical values were formulated by conducting ttests to derive p-values, to determine whether the change between periods was statistically significant. In addition, the communities were analyzed individually to identify the differences in water usage patterns between communities. The research detailed the relationship between seasonality and water usage among homes that received citations for violating irrigation restrictions. A comparative analysis was performed by obtaining the overall monthly averages of water usage within wet, moderate, and dry seasons for twice a week water restrictions and comparing them directly to the overall monthly averages of water usage within wet, moderate, and dry seasons for once a week water restrictions for cited violator homes. The percent change in water usage from twice a week water restrictions to once a week water restrictions was calculated to determine whether violators changed their water usage habits as restrictions changed. In addition, the cited violators within the individual communities were analyzed to determine the differences in enforcement response between communities. The difference in water usage for cited and uncited homes within each community for each period was also calculated to determine whether the cited violators skewed the overall sample.
Results A kernel density analysis was conducted for zip code 33647 (Fig. 2) to identify clusters of cited violations within the zip code using the Getis-ord Gi function. This information was then used to determine which communities would be used in this study. During the study period, there were 8860 cited water restriction violations within the City of Tampa (which contains 58 zip codes), and of those
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L.A. Ozan, K.A. Alsharif / Land Use Policy 31 (2013) 378–384 Table 2 Correlations between usage and rainfall during once and twice a week restrictive regimes. Community name
ALL West Meadows Hunter’s Green Arbor Greene
Twice a week
Once a week
r value
p-Value
Sig.
r value
p-Value
Sig.
−0.5940 −0.4447 −0.4959 −0.6954
0.0017 0.0259 0.0117 0.0001
Y Y Y Y
−0.5875 −0.2269 −0.4933 −0.7583
0.0020 0.2754 0.0122 0.0001
Y N Y Y
Table 3 Sampled communities’ mean water consumption. Community name
Twice a week
Once a week
% change
t-Test
p-Value
ALL West Meadows Hunter’s Green Arbor Greene
14,045 gal 12,525 gal 14,137 gal 15,027 gal
15,048 gal 12,566 gal 15,993 gal 15,325 gal
7.14 0.33 13.13 1.98
0.197 0.934 0.063 0.732
0.846 0.360 0.951 0.472
Table 4 All communities’ seasonal mean water usage (N = 225).
Fig. 2. Kernel density analysis of cited violators within zip code 33647.
15 10 5 0 -5
Apr-08
Feb-08
Oct-07
Dec-07
Jun-07
Aug-07
Apr-07
Feb-07
Oct-06
Dec-06
Jun-06
Aug-06
Apr-06
Feb-06
Oct-05
Dec-05
Jun-05
Aug-05
Apr-05
Feb-05
Oct-04
Dec-04
Jun-04
-10 Aug-04
Adjusted Rainfall in Inches
8860 violations, approximately 52% (4588) were recorded within zip code 33647. Approximately 62%, or 141, of the homes sampled had pools on the property, with an average usage of 14,565 gal per month. The 84 homes that did not have pools had an average usage of 14,535 gal per month. The difference in water usage between homes with pools and homes without pools was 0.21%. No further analysis was performed on this subject due to the negligible difference between the two groups. Historical and potential evapotranspiration rates place Tampa at a water deficit. The adjusted rainfall for historical pan evaporation gave Tampa a water surplus primarily from June through September and a water deficit for all other months in the study period, with the exception of February 2006 (Fig. 3). At a 0.05 confidence interval, the critical Pearson r-value was calculated to be 0.40. There is a significant negative correlation between rainfall and water usage throughout the entire study area. As a whole, all communities had a Pearson correlation coefficient (r) value of −0.59 for June 2004 through May 2006 (twice a week irrigation restrictions) and an r-value of −0.59 for June 2006 through May 2008 (once a week irrigation restrictions) (Table 2). The average monthly water consumption of the communities as a whole from June 2004 to May 2006 (the period with twice a week irrigation restrictions) was 14,045 gal, and from June 2006 to May 2008 (the period with once a week irrigation restrictions) was
Months
Fig. 3. Monthly surplus/deficits for June 2004 to May 2008. This figure indicates the actual adjusted rainfall obtained from local rainfall data and historical pan evaporation rates.
Season
Twice a week
Once a week
% change
Standard deviation
Wet Moderate Dry
11,743 gal 14,146 gal 16,248 gal
13,499 gal 15,268 gal 16,378 gal
14.96 7.93 0.80
2057 gal 1326 gal 3042 gal
15,048 gal. This finding indicates a 7.14% increase in usage from twice a week to once a week irrigation restrictions with a t-test p-value of 0.85 (Table 3). Therefore, there is no significant difference between twice a week and once a week watering. Peak usage was in March of 2007, with an average usage of 20,341 gal during once a week irrigation restrictions. Water usage was greatest from March through May in both 2006 and 2007. The range of difference in water consumption was 0.33–13.13%. Hunter’s Green by far exceeded the other two communities. Seasonality played a role in water usage during the study period. When the policy shifted from twice a week to once a week irrigation restrictions (Table 4), there was a 14.96% increase in water usage during the wet season (June through September), a 7.93% increase in water usage during the moderate season (October through January), and only 0.80% increase during the dry season (February through May). Of the 225 sampled homes, 67 (approximately 30%) had received one or more citations for violating irrigation restrictions. For these home, when the water usage restrictions changed from twice a week to once a week irrigation restrictions (Table 5), there was a 16.15% increase during the wet season, a 12.05% increase during the moderate season, and an 8.25% increase during the dry season. Peak usage by the cited homes is consistent across the 225 homes sampled, with peak usage occurring during March of 2007. Of the 225 sampled homes, 158 (approximately 70%) did not receive any citations for violating irrigation restrictions. There was a 15.54% increase in usage from twice a week to once a week irrigation restrictions during the wet season, a 6.19% increase during the moderate season, and a 2.53% decrease during the dry season (Table 6). A comparison of the monthly mean seasonal usage of all the cited homes to the monthly seasonal average of all the uncited Table 5 All communities’ mean water usage by cited violators (N = 67). Season
Twice a week
Once a week
% change
Standard deviation
Wet Moderate Dry
12,598 gal 15,315 gal 17,535 gal
14,633 gal 17,161 gal 18,981 gal
16.15 12.05 8.25
2346 gal 1741 gal 3758 gal
L.A. Ozan, K.A. Alsharif / Land Use Policy 31 (2013) 378–384 Table 6 Mean water usage of uncited homes (N = 158). Season
Twice a week
Once a week
% change
Standard deviation
Wet Moderate Dry
11,259 gal 13,619 gal 15,678 gal
13,009 gal 14,461 gal 15,282 gal
15.54 6.18 −2.53
2010 gal 1129 gal 2922 gal
Table 7 Cited homes’ vs. uncited homes’ seasonal mean water usage. Season
Uncited
Cited
% change
Standard deviation
Wet twice a week Mod twice a week Dry twice a week Wet once a week Mod once a week Dry once a week
11,380 gal 13,650 gal 15,702 gal 13,018 gal 14,465 gal 15,274 gal
12,598 gal 15,315 gal 17,535 gal 14,633 gal 17,161 gal 18,981 gal
10.70 12.20 11.67 12.41 18.64 24.27
2085 gal 1424 gal 3238 gal 2112 gal 1973 gal 4018 gal
homes reveals that the cited homes had greater usage during every season for twice a week irrigation restrictions and once a week irrigation restrictions. The percent change ranged from 10.70% in the wet seasonal monthly average for twice a week irrigation restrictions to 24.27% in the dry seasonal monthly average for once a week irrigation restrictions (Table 7). Discussion and conclusions The empirical results present several important findings regarding water usage in the specified northern Tampa communities. Swimming pools have a negligible effect on water usage, with only a 0.21% difference in consumption between pool owners and non-owners within the sampled communities. This negligible difference in water usage suggests that pool ownership is an insignificant contributor to domestic water consumption, leaving landscape irrigation as the primary contributor to outdoor usage. Average monthly rainfall proved to be the greatest indicator of water usage patterns. Each community’s water consumption had a significant negative correlation with precipitation, with the single exception being West Meadows during once a week irrigation restrictions. Overall, each community exhibited a high degree of responsiveness to rainfall in to domestic water usage. The data suggest that as rainfall increased, domestic water consumption decreased and that as rainfall decreased, domestic water consumption increased within the study area. This pattern could be attributed to the utilization of rain sensors. When visually surveying the study area, all homes were found to be in compliance with Florida Statute section 373.62. This statute requires that all automated irrigations systems installed in homes built after 1991 be equipped with a functional rain disengagement system to interrupt the operation of the irrigation system during and shortly preceding rainfall. The existence of this statute provides an explanation for the negative correlation between adjusted rainfall rates and domestic water consumption. This study did not attempt to measure the functionality of any individual home’s rain sensors. However, Statute 373.62 does require that the sensors be checked for functionality at least once annually. In addition, the City of Tampa provides free rain sensors to homeowners that have automated irrigation systems. Properly installing the rain sensor and setting the sensor to the proper threshold are crucial for achieving the goals of water conservation and acceptable turfgrass quality (McCready et al., 2009). Research suggests that rain sensors are the least effective water saving technologies available to consumers. The use of soil moisture sensors and evapotranspiration controllers is much more effective at reducing irrigation water use (Haley et al., 2010). Each community’s water consumption increased when Tampa’s irrigation restrictions transitioned from twice a week to once a
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week irrigation allowances. The p-values derived from the t-tests for each of these communities resulted in no statistical significance, although there were increases in usage from twice a week irrigation restrictions to once a week irrigation restrictions. Peak usage within each community remained consistent, with the highest usage taking place from March through May in 2006 and 2007; this consistency provides more evidence for the relationship between rainfall and consumption. These months represent the driest months as measured by rainfall adjusted by evaporation rates. Tampa Ordinance 2006-104 was introduced to mitigate domestic water use by decreasing the number of irrigation days from two to one per week. It is assumed that usage would decrease under once a week irrigation restrictions because the time allotted for watering was reduced by half. However, all communities examined in this study increased usage after the transition. Thus, it can be assumed that the examined communities were not compliant with the more stringent watering restrictions. When accounting for seasonality, the communities as a whole increased water consumption during all seasons. Nevertheless, Hunter’s Green had the largest seasonal increases for all seasons during the transition from twice a week to once a week irrigation restrictions. This provides further evidence that the data from Hunter’s Green skewed the overall averages. Of the 225 sampled homes, 67 received one or more citations for violating water restriction ordinances. Overall, the water consumption of the cited violators increased under once a week irrigation restrictions relative to twice a week irrigation restrictions. Hunter’s Green had the largest increase in usage for each season. Its large increases in usage throughout each of the seasons provide evidence that Hunter’s Green violators skewed the overall results for the combined sample of cited violators. Uncited homes represent 158 homes of the 225 sampled. Cited water restriction violators clearly skewed the results of the entire sample of 225 homes, their data demonstrated a greater increase in water usage after the wet season transition from twice a week irrigation restrictions. This finding suggests that the primary violators are being cited for their violations but that their water usage behavior is not being affected enough to decrease usage. This lack of an effect could be attributed to the small fine for violating the policy. When directly comparing cited violators to uncited homes, a consistent pattern was found. Cited violators had greater usage during each of the seasons compared to uncited homes. The volume used and percentage difference between twice a week and once a week irrigation restrictions for cited violators relative to uncited homes provide evidence that a disproportionate amount of the total water used within the study area. The results of this study depict an apparent disregard for the restrictions set forth by Tampa’s City Council. This disregard for the rules may be a product of many factors relating to enforcement, contradictory policies, and the culture of normative landscape practices. With regard to enforcement, the city does not have the financial or human resources needed to prosecute all violators. Therefore, it is highly debatable whether Council Members can adequately enforce these restrictions (Houck, 2002). There are two primary complications regarding enforcement: the delay in action subsequent to the violation and insufficient economic penalties to recoup enforcement expenditures (Houck, 2002). The cited violators included in this study were the greatest users of water resources, on average. Nevertheless, their usage behavior did not significantly change when the restrictions transitioned to a more stringent regime. Perhaps the violators simply weighed the options of either paying a minimal citation fee or risking having to replace costly landscaping. Not only is the penalty paid insufficient to change violator behavior, but also is insufficient to recoup the cost of the enforcement mechanism. The low fine for violating irrigation restrictions creates an atmosphere where the cited
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violator prefers to pay the fine rather than adhere to the restrictions (Alsharif, 2010). With regard to the contradictory policies, the ordinances produced by the City of Tampa create a major dilemma for homeowners that are bound by homeowner association standards that essentially promote non-adherence to irrigation restrictions. There is a perceived and measured association between well-maintained monocultured landscapes and property values, with which homeowner associations are concerned (Laverne and Windson-Geildeman, 2003). Many homeowner associations require groundcover that requires high water input to maintain an esthetically pleasing appearance, and most species of turfgrass require two or three scheduled irrigations a week to maintain their quality during the summer months (Trenholm et al., 2002). Tampa’s ordinances restricted watering to one or two times a week during the study period, with no regard for landscape watering requirements. This presents homeowners with a dilemma regarding whether to adhere to irrigation restrictions. The fine for violating any water restriction, per Tampa Code 26-97, is $100 for the first offense, $200 for the second offense, and $450 and a mandatory court appearance for the third and any subsequent offences. These appear to be monetary penalties that would promote adherence to the restrictions. Nevertheless, the cost for replacing 1000 square feet of turfgrass ranges from $300 to $1000, depending on the species of turf and whether the homeowner has the physical ability to perform the laborious task of installation. This estimated cost does not include the price of the irrigation needed to establish the lawn, which currently is not restricted by Tampa ordinances. The enforcement of the restrictions is also bound by time. Violators of the ordinances can water their lawn seven days a week if the homeowner sets their automated irrigation system to operate in the middle of the night when irrigation compliance officers are not available. With regard to lawn culture, research suggests that people associate well-maintained landscapes with high home values and community connectivity (Robbins et al., 2001). Researchers also contend that the aspiration to sustain one’s yard may be motivated in part by the desire for neighborhood solidarity and/or conflict avoidance (Hirsch and Baxter, 2009). Therefore, residents may perceive compliance with water restrictions as a sign of neighborhood degradation, and thus attempt to avoid conflicts with neighbors by maintaining normative yard care standards (Hirsch and Baxter, 2009). Arguably, the lawn’s greatest role in the social process is ideological; it supports a set of concepts and standards about the way a society should be organized (Feagan and Ripmeester, 2001). The multiple dynamics of lax enforcement, contradictory policies, and the general culture of normative landscape practices provide clear disincentives for compliance with irrigation restrictions. Further research should focus on determining the relationship between parcel size, home size, and domestic water usage. This research could provide useful information for understanding whether water use increases proportionately with parcel size and could help determine whether the size of the home or the size of the lot, has a significant relationship with water usage. Examining the relationship between home value as a proxy for income level and water usage within Tampa communities would also provide valuable information about the socioeconomic factors that could lead to increased water usage. Qualitative research regarding water restriction adherence and knowledge could be another avenue for exploration to provide a further understanding of the reasons and rationales for compliance and non-compliance with irrigation restrictions. This study makes several assumptions regarding individual behavior and the reasons
for non-compliance with the restrictions. The effects of community solidarity, conflict avoidance, and conflicts between local policy and binding community rules could be more effectively measured through a qualitative study, such as, one based on primary data from surveys or interviews. References Alsharif, K., 2010. Construction and stormwater pollution: policy, violations, and penalties. Land Use Policy 27, 612–616. Brennan, D., Tapsuwan, S., Ingram, G., 2007. The welfare costs of urban outdoor water restrictions. Australian Journal of Agricultural and Resource Economics 51, 243–261. City of Tampa, 2009. Water Use Restrictions (04.10.09) http://www.tampagov.net/ dept water/information resources/restrictions/ Dandy, G., 1992. Assessing the economic cost of restrictions on outdoor water use. Water Resources Research 28, 1759–1766. ESRI, 2008. Arc News Online (03.11.10) http://www.esri.com/news/arcnews/ winter0809articles/tampa-bay-water.html Feagan, R., Ripmeester, M., 2001. Reading private green space: competing geographic identities at the level of the lawn. Philosophy and Geography 4, 79–95. Grafton, R.Q., Ward, M.B., 2008. Prices versus rationing: Marshallian surplus and mandatory water restrictions. Economic Record 84, S57–S65. Haley, M.B., Dukes, M.D., Davis, S., Shedd, M., Lailhacar, B.C., 2010. Energy Efficient Homes: The Irrigation System. University of Florida Publication, Gainesville, FL, FCS3274. Haley, M.B., Dukes, M.D., Miller, G.L., 2007. Residential irrigation water use in central Florida. Journal of Irrigation and Drainage Engineering 133, 427–434. Hillsborough County, 2010. About the County (03.11.10) http://www. hillsboroughcounty.org/about/ Hirsch, R., Baxter, J., 2009. The look of the lawn: pesticide policy preference and health-risk perception. Environment and Planning C: Government and Policy 27, 468–490. Houck, O., 2002. The Clean Water Act TMDL Program: Law, Policy, and Implementation. Environmental Law Institute, Washington, DC, pp. 179–180. Hunter’s Green Community Association, Inc., 2012. Lawn Maintenance Guide(15.04.12) http://www.huntersgreen.com/pdf/Rules Regulations/ lines Lawn Maintenance Guidelines.pdf Kenney, D.S., Klein, R.A., Clark, M.P., 2004. Use and effectiveness of municipal water restrictions during drought in Colorado. Journal of the American Water Resources Association 40, 77–87. Laverne, R.J., Windson-Geildeman, K., 2003. The influence of trees and landscaping on rental rates at office buildings. Journal of Arboriculture 29, 281–290. Lund, J.R., 1995. Drought water rationing and transferable rations. Journal of Water Resources Planning and Management 121, 429–437. Mayer, P.W., D’Oreo, W.B., Opitz, E.M., Kiefer, J.C., Davis, W.Y., Dziegielewski, B., Nelson, J.O., 1999. Residential End Uses of Water. AWWA Research Foundation, Denver, CO. McCready, M.S., Dukes, M.D., Miller, G.L., 2009. Water conservation potential of smart irrigation controllers on St. Augustine grass. Agricultural Water Management 96, 1623–1632. Mercer, L.J., Morgan, W.D., 1989. Welfare effects of alternative water rationing schemes: a case study. Water Resource Bulletin 25, 203–210. Nagel, S.S., 1990. Bridging theory and practice in policy/program evaluation. Evaluation and Program Planning 13, 275–283. Nelson, J.O., 1979. Northern California rationing lessons. In: Conference on Water Conservation Needs and Implementing Strategies, Franklin Pierce College, Rindge, NH, July 9–13, 1979, pp. 139–146. Pereira, L.S., Theib, O., Abdelaziz, Z., 2002. Irrigation management under water scarcity. Agricultural Water Management 57, 175–206. Renwick, M.E., Archibald, S.O., 1998. Demand side management policies for residential water use: who bears the conservation burden? Land Economics 74, 343–359. Robbins, P., Birkenholtz, T., 2003. Turfgrass revolution: measuring the expansion of the American lawn. Land Use Policy 20, 181–194. Robbins, P., Polderman, A., Trevor, B., 2001. Lawns and toxins: an ecology of the city. Cities 18, 369–380. SWFWMD, 2009. Water Restrictions (04.10.09) http://www.swfwmd.state.fl.us/ conservation/restrictions/swfwmd.html Timmins, C., 2003. Demand-side technology standards under inefficient pricing regimes. Environmental Resource Economics 26, 107–124. Trenholm, L.E., Gilman, E.F., Knox, G.W., Black, R.J., 2002. Fertilization and Irrigation Needs for Florida Lawns and Landscapes. University of Florida Publication, Gainesville, FL, ENH860. Trenholm, L.E., Cisar, J.L., Unruh, J.B., 1991. St. Augustine Grass for Florida Lawns. University of Florida Publication, Gainesville, FL, ENH5. U.S. Census Bureau, 2011. Quick Facts (12.04.11) http://quickfacts.census.gov/ qfd/states/12000.html West Meadows Property Owners Association, Inc., 2012. Sod Alternatives Approved for West Meadows (12.04.12) http://www.west-meadows.org/ rulesandregulations/lawns.html.
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The effectiveness of water irrigation policies for residential turfgrass Lin A. Ozan, Kamal A. Alsharif ∗ Department of Geography, Environment, and Planning, 4202 East Fowler Avenue, NES 107, University of South Florida, Tampa, FL 33620, United States
a r t i c l e
i n f o
Article history: Received 16 February 2012 Received in revised form 31 July 2012 Accepted 1 August 2012 Keywords: Turfgrass Domestic water policy Restrictions Citations Lawns
a b s t r a c t Turfgrass irrigation policies have been implemented in various regions of the U.S. to reduce domestic water consumption. Mandatory restrictions are often enforced by issuing citations to violators with the intent to promote compliance and deter violations. This study provides a detailed investigation of past water restrictions and compliance, and attempts to determine which factors are related to high rates of water usage within communities of Tampa, FL. The adjusted rainfall rate had the most significant relationship with water usage in the communities under study. Water usage increased in each examined community after it transitioned to more stringent water usage restrictions, with cited restriction violators increasing usage to a greater extent than their uncited counterparts. This increase may primarily be attributed to conflicts between the local water consumption policy and binding homeowner association rules. When the once-a-week usage restriction was in place, the area faced drought conditions. Therefore, homeowners irrigated more to meet the water needs of their lawns despite the restrictions imposed on them by their local government. © 2012 Elsevier Ltd. All rights reserved.
Introduction An enormous amount of water is being used on turfgrass in many situations where water is limited or even scarce. For example, in the arid region of the American West, lawn irrigation by one measure exceeds 50% of domestic water usage (Mayer et al., 1999). Lawn irrigation represents the largest portion of domestic water usage across the U.S. (Mayer et al., 1999). In addition, lawn irrigation accounts for at least half of all water consumed by the domestic sector in most Australian capital cities (Brennan et al., 2007). Furthermore, automated systems typically do not distribute water uniformly to appropriately irrigate turf landscapes, and they have many inherent inefficiencies that increase water loss (Haley et al., 2010). Therefore, restricting outdoor water usage provides an excellent opportunity to mitigate domestic usage. Kenney et al. (2004) examined data from regions with mandatory and voluntary water restrictions that primarily focused on limiting residential lawn watering during a prolonged Colorado drought. They found that mandatory restrictions resulted in more limited water use than voluntary restrictions, even when accounting for climatic variation across the studied areas. Water restrictions can be useful for mitigating domestic water usage, but a restrictive policy is only as effective as the enforcement mechanism. Extensive research is crucial to determine if whether current
∗ Corresponding author. Tel.: +1 813 974 4883; fax: +1 813 974 4808. E-mail addresses: [email protected] (L.A. Ozan), [email protected] (K.A. Alsharif). 0264-8377/$ – see front matter © 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.landusepol.2012.08.001
restrictions should be maintained or restructured to further mitigate domestic water usage. The policies examined do not consider the amount of water required to sustain a healthy lawn but instead are designed to conserve water and only maintain the population’s essential water requirements. St. Augustine and Bermuda grass, the grass species typically recommended by deed-restricted communities in Florida suburbs (Trenholm et al., 1991) require two or three scheduled irrigations a week to maintain acceptable quality during the summer months (Trenholm et al., 2002). Tampa’s policies have historically alternated between prolonged periods of restricting irrigation to watering either once or twice a week; this requirement creates a dilemma for homeowners who are required by their binding community rules to maintain healthy turfgrass. To better understand the compatibility of local policy and binding community directives, this study determined residential water use patterns and magnitudes within deed-restricted communities and mapped enforcement mechanisms using high-resolution geographic information system (GIS) analysis and other strategic mapping methods at the community level. Specifically, this study (1) developed GIS data sets that were used to quantitatively map water usage at the parcel level; (2) examined the relationship between domestic water usage and key environmental and recreational factors, such as rainfall, seasonality, and the presence of swimming pools; and (3) mapped the enforcement of residential lawn irrigation policy non-compliance to determine spatial relationships within and between the communities and to test the effectiveness of current enforcement practices. This study focused on three deed-restricted communities located in northern Tampa, FL. An in-depth investigation into domestic water usage in such
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Table 1 Irrigation restrictions enacted during different time periods in the City of Tampa. City ordinance 2000-69
City ordinance 2003-316
City ordinance 2006-104
March 16th 2000 to November 24th 2003 Addresses ending with an even number or letters A through M, only on Tuesdays
November 25th 2003 to May 4th 2006 Addresses ending with an even number or letters A through M, only on Tuesdays and Saturdays Addresses ending with an odd number or letters N through Z, only on Sunday and Wednesday Irrigation of properties was prohibited from 8:00 a.m. to 6:00 p.m. on permitted days Irrigation prohibited at all times on Monday, Thursday, and Friday
May 5th 2006 to December of 2010 Addresses ending with an even number or letters A through M, only on Tuesdays
Addresses ending with an odd number or letters N through Z, only on Sundays Irrigation of properties was prohibited from 8:00 a.m. to 6:00 p.m. on permitted days Irrigation prohibited at all times on Monday, Wednesday, Thursday, Friday, and Saturday
communities would ultimately help environmental managers to effectively enact and enforce policies that are aimed at protecting our most precious resource. Cultural perspectives on the lawn The current ideal of the monoculture lawn can be traced to the landscapes constructed by privileged French and British individuals in the 16th and 17th centuries and is a variation on their scale and structure (Feagan and Ripmeester, 2001). It has also been tied to statesmen such as Andrew Jackson Downing and Thomas Jefferson, who envisioned the landscape as being intertwined with the progress of democracy, liberty, and moral health (Feagan and Ripmeester, 2001). Downing held that people’s pride in their country was tied to pride in their homes, and to show patriotism and pride, they must tend to their homes appropriately. This ideology was perpetuated throughout the formation and industrialization of the United States. Currently, a lawn is no longer an elitist means of displaying patriotism. Americans have become more affluent and have expanded their personal landholdings to the suburbs, which have promoted the expansion of the lawn (Robbins and Birkenholtz, 2003). The post-World War II era of nationalism, identity, and community led to shifts in work and leisure activities. The lawn has become associated with private enterprise and personal property. It has grown beyond its physical presence to become a symbol of public order. A well-maintained lawn is an essential element in developing an appropriate social and moral order (Feagan and Ripmeester, 2001). The commodification of the lawn and the esthetics associated with it are now a reflection of purity, cleanliness, and decency within the American suburb (Feagan and Ripmeester, 2001). Researchers suggest that the aspiration to maintain one’s yard may be motivated in part by the desire for neighborhood solidity and/or conflict avoidance (Hirsch and Baxter, 2009). In addition, residents may perceive conformity with water restrictions as a sign of neighborhood degradation, and they therefore are encouraged to avoid conflicts with neighbors by maintaining yard care standards (Hirsch and Baxter, 2009). Arguably, the lawn’s greatest role in the social process is ideological; it supports a set of concepts and norms regarding the way a society should be organized (Feagan and Ripmeester, 2001). In addition to the aspiration for community solidarity, many homeowners are obligated to follow the directives of their homeowner associations. In Florida, many homeowner associations have adapted their own lawn policies. For example, Hunter’s Green Community Association, a community included in this study, permits only St. Augustine turfgrass; it also mandates that irrigation systems must cover 100% of the lawn; and that watering must comply with local and state policies (Hunter’s Green Community Association Inc., 2012). On the other hand, the West Meadows
Addresses ending with an odd number or letters N through Z, only on Sundays Irrigation of properties was prohibited from 8:00 a.m. to 6:00 p.m. on permitted days Irrigation prohibited at all times on Monday, Wednesday, Thursday, Friday, and Saturday
Community Association permits St. Augustine, Bahia, Bermuda, and Zoysia grass, and holds the homeowner responsible for maintaining a healthy and acceptable lawn (West Meadows Property Owners Association Inc., 2012). Thus, the homeowners must have the knowledge necessary to meet their community associations’ policies and healthy lawn requirements. Noncompliance due to a lack of knowledge is not considered an excuse. In addition, some of the language in the homeowners’ manuals is open to interpretation. For example, how does the West Meadows Homeowners Association define a healthy and acceptable lawn? Is lawn health a matter of the individual homeowner’s subjective interpretation or are there criteria specified in a document? Tampa’s historical local irrigation policy The water demanded by Tampa citizens has periodically exceeded availability over the past few decades; in these instances, water was purchased from suppliers to meet demand. Contributing factors include inadequate rainfall, escalating irrigation demands, and decreased flows into the Hillsborough River (Water Restrictions, 2009). In addition, the decreased flows into the Hillsborough River have caused Tampa’s reservoir levels to decline more rapidly and recover more slowly than in past years. Tampa’s reservoir provides 90% of the treated water distributed to Tampa Water Department customers and is the primary source of drinking water for the city. To conserve water resources, water usage restrictions have been enacted to help ensure a sufficient quantity of indoor water for the Tampa community (City of Tampa, 2009). The City of Tampa’s outdoor water use restrictions are in effect for all residents within the incorporated city limits and for residents outside the incorporated city limits to the extent permitted by law. However, hand watering of new and existing lawns was not restricted. For the past decade, Tampa’s water restrictions have oscillated between once a week and twice a week automated lawn irrigation to curb demand and preserve water resources. The irrigation restrictions were enacted at different times and covered different time periods (Table 1). As Table 1 shows, the restrictions controlled the days and times that homeowners could irrigate their lawns. In addition, both once and twice a week policies were used. More stringent policies were in effect in Tampa during the Spring of 2009. This policy restricted lawn irrigation to hand watering only. This common water restriction is usually implemented to completely ban the use of automated, in-ground sprinkler systems and permits households to substitute for it with labor-intensive hand-held watering (Brennan et al., 2007). Policy effectiveness There are four primary types of domestic water conservation and mitigation strategies used in the United States: rationing
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(Nelson, 1979; Mercer and Morgan, 1989; Lund, 1995), usage restrictions (Mayer et al., 1999; Kenney et al., 2004; Brennan et al., 2007), pricing (Dandy, 1992; Timmins, 2003; Brennan et al., 2007; Grafton and Ward, 2008), and technology (Renwick and Archibald, 1998; Pereira et al., 2002; Haley et al., 2007; McCready et al., 2009). There is a difference between rationing and usage restrictions. Rationing traditionally reduces the amount used through fixed allotments, percentage reductions, and conservation credits (Lund, 1995; Nelson, 1979). However, a usage restriction bans the use of water for irrigation outside of certain days or times. The four primary types of domestic water conservation strategies are not mutually exclusive, and hybridized versions incorporate elements of multiple strategies. The literature does not arrive at a clear consensus as to which stand-alone strategy is the most effective. This lack of consensus is due to the multitude of different variables within each specific study area. One of the most crucial steps in the policy cycle is the evaluation of policy. Measuring the effectiveness of a policy is paramount in determining whether the policy should remain as is, or be modified to produce better results. The key criteria for policy evaluation include validity, importance, usefulness, originality, and feasibility (Nagel, 1990). The City of Tampa’s policies mentioned above were formulated to eliminate unessential domestic water usage. Unessential usage reflects what the City of Tampa deems unnecessary and includes domestic irrigation. However, some homeowners consider irrigating their turfgrass to be an important component of their water usage. Nevertheless, such a policy is valid when the availability of water for essential human requirements is compromised. Drought conditions in the region have threatened Florida’s water security, and water conservation policies are of grave importance. However, without an around-the-clock enforcement mechanism coupled with citizen adherence, local government policies cannot be feasibly enforced. This study sought to determine the effectiveness of the aforementioned restrictions. Study area Tampa is located midway along the west coast of Florida and serves as the administrative center for Hillsborough County. Its incorporated boundaries total 170.6 square miles, which include 112.1 square miles of land and 58.5 square miles of water (Hillsborough County, 2010). Tampa’s current population is 335,709, a 10.6% increase from the 2000 United States Census figure (U.S. Census Bureau, 2011). The study area comprises key communities within the City of Tampa’s zip code (33647) that are bounded by Interstate 75 to the south and west, Morris Bridge Road to the east, and County Line Road to the north (Fig. 1). The communities are West Meadows, Hunter’s Green, and Arbor Greene. According to the Southwest Florida Water Management District (SWFWMD) (2009), Tampa, was under a phase III extreme water shortage alert during thirty of the sixty months examined in this study. However, the data analysis covered only 48 months, from June 2004 to May 2008, to obtain an equal number of months for twice and once a week irrigation restrictions. SWFWMD analyses of drought indicators (rainfall, groundwater levels, and stream flows) characterize conditions as normal or one of four degrees of abnormality. These four degrees are moderate, severe, extreme, and critical, and they are based on a comparison with historical data (SWFWMD, 2009). Increased ambient air temperature, in conjunction with decreased precipitation rates and increasing water usage, has in the past driven the city into the critical category and can potentially do so in the future. Throughout the last decade, Tampa has experienced varying degrees of abnormality. In response, the City of Tampa adopted water restriction policies based on SWFWMD recommendations, with the water authority overseeing compliance. The city
Fig. 1. Map of Tampa, Florida zip code 33647.
adopted specific policies to curtail domestic water usage within the city’s incorporated boundaries during the forty-eight-month study period. The area with the highest incidence of enforced irrigation violations is zip code 33647. Conventional wisdom would dictate that this zip code would be the perfect area to determine whether the enforcement of and adherence to the city’s watering restrictions are effective at reducing domestic water usage, because of the noncompliance citations. The three communities of West Meadows, Hunter’s Green, and Arbor Greene have been hotspots for cited water use violations in the past decade. The residents of these deed-restricted communities are placed in a difficult position. These single-family homeowners are required by the City of Tampa to limit lawn irrigation and by their binding community rules to maintain a healthy green lawn. The residents must choose either to adhere to Tampa’s restrictions or homeowner association’s requirements to avoid a monetary penalty, or devise inventive irrigation methods that avoid community and legislative backlash. Methods The data set summarizes water usage by month during once a week and twice a week restrictive periods. The water usage data were obtained from Tampa Bay Water, and they include water usage by month for individual addresses throughout the City of Tampa. The data were acquired from Tampa Bay Water’s GOVNET program. Indoor water use was assumed to be constant over the course of the year. Thus, seasonal and inter-annual variations were most likely due to outdoor water use. In June 2007, Tampa Bay Water began to develop a high-resolution water distribution application for analyzing water usage obtained from archival and current billing records. The ensuing application was named GOVNET and was used to manage all future water conservation efforts. The data reside in Tampa Bay Water’s enterprise GIS, which incorporates a multi-terabyte ArcSDE geo-database server and numerous non-spatial SQL servers to accumulate differing water quality, consumption, SCADA, and wetland data (ESRI, 2008). The data comprise
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time-series billing data from all member governments: Hillsborough County, Pasco County, Pinellas County, City of New Port Richey, City of St. Petersburg, and the City of Tampa. All data were recorded on a monthly basis from 1998 to the present for over 500,000 individual water use accounts and were geo-coded to a physical parcel (ESRI, 2008). This source was used to create a data set that was useful for the present analysis. The selection of the study areas was strategic, in that the areas had to meet three specific criteria to be included in the study. First, the areas could not have reclaimed water available to use for irrigation. If the areas had reclaimed water available, domestic usage would potentially be highly skewed and non-representative. Second, major construction of the community within the neighborhoods to be examined must have begun the last twenty years, and the individual homes examined must have been built before 2003. This criterion ensured that the homes examined were equipped with automated in-ground irrigation systems and that individual homes had existing lawns before the study began. Third, the communities examined were required to be cited violation hotspots. This criterion ensured that the results of the study accurately depict the effectiveness of the restrictive policies. After all specified qualifications for community selection were met, a kernel density analysis using the Getis-ord Gi function was conducted within zip code 33647 to determine which communities or neighborhoods had clusters of cited violations. A base map was created using GIS data from the Hillsborough County Property Appraiser’s February 2010 assessment. Only parcels with single-family homes built before 2003 were used for the map. Within this landscape, research focus areas were selected. Sampling was used due to the large volume of data that would otherwise be individually recorded for each month for each parcel. The three hotspot communities of West Meadows, Hunter’s Green, and Arbor Greene were chosen due to high incidences of cited water restriction violations and the availability of water usage data. Each parcel with an associated single-family home built before 2003 in each of these communities was systematically numbered for quick reference. Two hundred twenty-five homes within the specified communities (49 in West Meadows, 112 in Hunter’s Green, and 64 in Arbor Greene) were chosen by random number generation software, representing approximately 10% of the homes built before 2003 within the three communities. The 225 sampled homes provide for a 6.31% margin of error at a 95% confidence level from the total population of 3203 single-family homes. The address of each selected home was used to query the GOVNET database. The water usage data were extracted from the database for the sampled households for the duration of the study. To construct the GIS data set, the following attributes were recorded for each of the selected homes: address (ADDRESS), the parcel’s square footage (PSQFT), the presence or absence of a pool (POOL), citation dates (CITATION1, CITAION2, and CITATION3), neighborhood name (NEIGHBORHOOD) and monthly water usage from December 2003 through November 2008. The duration of the study was chosen by selecting equal intervals of once a week and twice a week watering restrictions, beginning and ending with the same month. Twice a week irrigation restrictions went into effect on November 25, 2003, and were replaced by once a week irrigation restrictions on May 5, 2006. Therefore, data from June 2004 through May 2008 were employed, for a total of 48 months. This data set encompassed 24 months of twice a week watering restrictions (June 2004–May 2006) and 24 months of once a week watering restrictions (June 2006–May 2008). The individual months were then grouped into wet, moderate, and dry seasons based on local rainfall data and historical pan evaporation rates. The rainfall data were collected from a weather data collector maintained by the USGS, located approximately 8 miles from the study area. The rainfall data were then adjusted by historical
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evapotranspiration rates, determined by NOAA for the Tampa metropolitan statistical area, to establish grouped seasons based on actual data. The wet season includes the months of June, July, August, and September. The moderate season includes the months of October, November, December, and January. The dry season includes the months of February, March, April, and May. The average monthly water usage of homes with pools and homes without pools were calculated to determine whether there was a significant relationship between water usage and pool ownership. Next, domestic water usage was tested for any relationship with rainfall patterns. This was accomplished by obtaining the overall monthly average water usage from June 2004 to May 2006 (twice a week irrigation restrictions) and comparing it to the overall monthly average water usage through June of 2006 to May of 2008 (once a week irrigation restrictions). The Pearson’s r correlation coefficient was calculated using monthly rainfall totals and monthly water usage totals for each of the two periods. The correlation coefficient was calculated for the study area as a whole and for each individual community during both periods to determine which community, if any, had the greatest water usage in the area. The correlation coefficients were tested for significance by determining the critical value at a 0.05 confidence interval. The fourth step of the research detailed the relationship between seasonality and water usage. This step was accomplished by dividing the data into months of wet, moderate, and dry conditions based on monthly rainfall and local evapotranspiration rates. Next, a comparative analysis was initiated by obtaining the overall monthly average water usage within each season from June 2004 to May 2006 (twice a week irrigation restrictions) and comparing it to the overall monthly average water usage within each season from June 2006 to May 2008 (once a week irrigation restrictions). The percent change in water usage from twice a week irrigation restrictions to once a week irrigation restrictions was calculated to determine whether water usage changed with the modification of restrictions. Statistical values were formulated by conducting ttests to derive p-values, to determine whether the change between periods was statistically significant. In addition, the communities were analyzed individually to identify the differences in water usage patterns between communities. The research detailed the relationship between seasonality and water usage among homes that received citations for violating irrigation restrictions. A comparative analysis was performed by obtaining the overall monthly averages of water usage within wet, moderate, and dry seasons for twice a week water restrictions and comparing them directly to the overall monthly averages of water usage within wet, moderate, and dry seasons for once a week water restrictions for cited violator homes. The percent change in water usage from twice a week water restrictions to once a week water restrictions was calculated to determine whether violators changed their water usage habits as restrictions changed. In addition, the cited violators within the individual communities were analyzed to determine the differences in enforcement response between communities. The difference in water usage for cited and uncited homes within each community for each period was also calculated to determine whether the cited violators skewed the overall sample.
Results A kernel density analysis was conducted for zip code 33647 (Fig. 2) to identify clusters of cited violations within the zip code using the Getis-ord Gi function. This information was then used to determine which communities would be used in this study. During the study period, there were 8860 cited water restriction violations within the City of Tampa (which contains 58 zip codes), and of those
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L.A. Ozan, K.A. Alsharif / Land Use Policy 31 (2013) 378–384 Table 2 Correlations between usage and rainfall during once and twice a week restrictive regimes. Community name
ALL West Meadows Hunter’s Green Arbor Greene
Twice a week
Once a week
r value
p-Value
Sig.
r value
p-Value
Sig.
−0.5940 −0.4447 −0.4959 −0.6954
0.0017 0.0259 0.0117 0.0001
Y Y Y Y
−0.5875 −0.2269 −0.4933 −0.7583
0.0020 0.2754 0.0122 0.0001
Y N Y Y
Table 3 Sampled communities’ mean water consumption. Community name
Twice a week
Once a week
% change
t-Test
p-Value
ALL West Meadows Hunter’s Green Arbor Greene
14,045 gal 12,525 gal 14,137 gal 15,027 gal
15,048 gal 12,566 gal 15,993 gal 15,325 gal
7.14 0.33 13.13 1.98
0.197 0.934 0.063 0.732
0.846 0.360 0.951 0.472
Table 4 All communities’ seasonal mean water usage (N = 225).
Fig. 2. Kernel density analysis of cited violators within zip code 33647.
15 10 5 0 -5
Apr-08
Feb-08
Oct-07
Dec-07
Jun-07
Aug-07
Apr-07
Feb-07
Oct-06
Dec-06
Jun-06
Aug-06
Apr-06
Feb-06
Oct-05
Dec-05
Jun-05
Aug-05
Apr-05
Feb-05
Oct-04
Dec-04
Jun-04
-10 Aug-04
Adjusted Rainfall in Inches
8860 violations, approximately 52% (4588) were recorded within zip code 33647. Approximately 62%, or 141, of the homes sampled had pools on the property, with an average usage of 14,565 gal per month. The 84 homes that did not have pools had an average usage of 14,535 gal per month. The difference in water usage between homes with pools and homes without pools was 0.21%. No further analysis was performed on this subject due to the negligible difference between the two groups. Historical and potential evapotranspiration rates place Tampa at a water deficit. The adjusted rainfall for historical pan evaporation gave Tampa a water surplus primarily from June through September and a water deficit for all other months in the study period, with the exception of February 2006 (Fig. 3). At a 0.05 confidence interval, the critical Pearson r-value was calculated to be 0.40. There is a significant negative correlation between rainfall and water usage throughout the entire study area. As a whole, all communities had a Pearson correlation coefficient (r) value of −0.59 for June 2004 through May 2006 (twice a week irrigation restrictions) and an r-value of −0.59 for June 2006 through May 2008 (once a week irrigation restrictions) (Table 2). The average monthly water consumption of the communities as a whole from June 2004 to May 2006 (the period with twice a week irrigation restrictions) was 14,045 gal, and from June 2006 to May 2008 (the period with once a week irrigation restrictions) was
Months
Fig. 3. Monthly surplus/deficits for June 2004 to May 2008. This figure indicates the actual adjusted rainfall obtained from local rainfall data and historical pan evaporation rates.
Season
Twice a week
Once a week
% change
Standard deviation
Wet Moderate Dry
11,743 gal 14,146 gal 16,248 gal
13,499 gal 15,268 gal 16,378 gal
14.96 7.93 0.80
2057 gal 1326 gal 3042 gal
15,048 gal. This finding indicates a 7.14% increase in usage from twice a week to once a week irrigation restrictions with a t-test p-value of 0.85 (Table 3). Therefore, there is no significant difference between twice a week and once a week watering. Peak usage was in March of 2007, with an average usage of 20,341 gal during once a week irrigation restrictions. Water usage was greatest from March through May in both 2006 and 2007. The range of difference in water consumption was 0.33–13.13%. Hunter’s Green by far exceeded the other two communities. Seasonality played a role in water usage during the study period. When the policy shifted from twice a week to once a week irrigation restrictions (Table 4), there was a 14.96% increase in water usage during the wet season (June through September), a 7.93% increase in water usage during the moderate season (October through January), and only 0.80% increase during the dry season (February through May). Of the 225 sampled homes, 67 (approximately 30%) had received one or more citations for violating irrigation restrictions. For these home, when the water usage restrictions changed from twice a week to once a week irrigation restrictions (Table 5), there was a 16.15% increase during the wet season, a 12.05% increase during the moderate season, and an 8.25% increase during the dry season. Peak usage by the cited homes is consistent across the 225 homes sampled, with peak usage occurring during March of 2007. Of the 225 sampled homes, 158 (approximately 70%) did not receive any citations for violating irrigation restrictions. There was a 15.54% increase in usage from twice a week to once a week irrigation restrictions during the wet season, a 6.19% increase during the moderate season, and a 2.53% decrease during the dry season (Table 6). A comparison of the monthly mean seasonal usage of all the cited homes to the monthly seasonal average of all the uncited Table 5 All communities’ mean water usage by cited violators (N = 67). Season
Twice a week
Once a week
% change
Standard deviation
Wet Moderate Dry
12,598 gal 15,315 gal 17,535 gal
14,633 gal 17,161 gal 18,981 gal
16.15 12.05 8.25
2346 gal 1741 gal 3758 gal
L.A. Ozan, K.A. Alsharif / Land Use Policy 31 (2013) 378–384 Table 6 Mean water usage of uncited homes (N = 158). Season
Twice a week
Once a week
% change
Standard deviation
Wet Moderate Dry
11,259 gal 13,619 gal 15,678 gal
13,009 gal 14,461 gal 15,282 gal
15.54 6.18 −2.53
2010 gal 1129 gal 2922 gal
Table 7 Cited homes’ vs. uncited homes’ seasonal mean water usage. Season
Uncited
Cited
% change
Standard deviation
Wet twice a week Mod twice a week Dry twice a week Wet once a week Mod once a week Dry once a week
11,380 gal 13,650 gal 15,702 gal 13,018 gal 14,465 gal 15,274 gal
12,598 gal 15,315 gal 17,535 gal 14,633 gal 17,161 gal 18,981 gal
10.70 12.20 11.67 12.41 18.64 24.27
2085 gal 1424 gal 3238 gal 2112 gal 1973 gal 4018 gal
homes reveals that the cited homes had greater usage during every season for twice a week irrigation restrictions and once a week irrigation restrictions. The percent change ranged from 10.70% in the wet seasonal monthly average for twice a week irrigation restrictions to 24.27% in the dry seasonal monthly average for once a week irrigation restrictions (Table 7). Discussion and conclusions The empirical results present several important findings regarding water usage in the specified northern Tampa communities. Swimming pools have a negligible effect on water usage, with only a 0.21% difference in consumption between pool owners and non-owners within the sampled communities. This negligible difference in water usage suggests that pool ownership is an insignificant contributor to domestic water consumption, leaving landscape irrigation as the primary contributor to outdoor usage. Average monthly rainfall proved to be the greatest indicator of water usage patterns. Each community’s water consumption had a significant negative correlation with precipitation, with the single exception being West Meadows during once a week irrigation restrictions. Overall, each community exhibited a high degree of responsiveness to rainfall in to domestic water usage. The data suggest that as rainfall increased, domestic water consumption decreased and that as rainfall decreased, domestic water consumption increased within the study area. This pattern could be attributed to the utilization of rain sensors. When visually surveying the study area, all homes were found to be in compliance with Florida Statute section 373.62. This statute requires that all automated irrigations systems installed in homes built after 1991 be equipped with a functional rain disengagement system to interrupt the operation of the irrigation system during and shortly preceding rainfall. The existence of this statute provides an explanation for the negative correlation between adjusted rainfall rates and domestic water consumption. This study did not attempt to measure the functionality of any individual home’s rain sensors. However, Statute 373.62 does require that the sensors be checked for functionality at least once annually. In addition, the City of Tampa provides free rain sensors to homeowners that have automated irrigation systems. Properly installing the rain sensor and setting the sensor to the proper threshold are crucial for achieving the goals of water conservation and acceptable turfgrass quality (McCready et al., 2009). Research suggests that rain sensors are the least effective water saving technologies available to consumers. The use of soil moisture sensors and evapotranspiration controllers is much more effective at reducing irrigation water use (Haley et al., 2010). Each community’s water consumption increased when Tampa’s irrigation restrictions transitioned from twice a week to once a
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week irrigation allowances. The p-values derived from the t-tests for each of these communities resulted in no statistical significance, although there were increases in usage from twice a week irrigation restrictions to once a week irrigation restrictions. Peak usage within each community remained consistent, with the highest usage taking place from March through May in 2006 and 2007; this consistency provides more evidence for the relationship between rainfall and consumption. These months represent the driest months as measured by rainfall adjusted by evaporation rates. Tampa Ordinance 2006-104 was introduced to mitigate domestic water use by decreasing the number of irrigation days from two to one per week. It is assumed that usage would decrease under once a week irrigation restrictions because the time allotted for watering was reduced by half. However, all communities examined in this study increased usage after the transition. Thus, it can be assumed that the examined communities were not compliant with the more stringent watering restrictions. When accounting for seasonality, the communities as a whole increased water consumption during all seasons. Nevertheless, Hunter’s Green had the largest seasonal increases for all seasons during the transition from twice a week to once a week irrigation restrictions. This provides further evidence that the data from Hunter’s Green skewed the overall averages. Of the 225 sampled homes, 67 received one or more citations for violating water restriction ordinances. Overall, the water consumption of the cited violators increased under once a week irrigation restrictions relative to twice a week irrigation restrictions. Hunter’s Green had the largest increase in usage for each season. Its large increases in usage throughout each of the seasons provide evidence that Hunter’s Green violators skewed the overall results for the combined sample of cited violators. Uncited homes represent 158 homes of the 225 sampled. Cited water restriction violators clearly skewed the results of the entire sample of 225 homes, their data demonstrated a greater increase in water usage after the wet season transition from twice a week irrigation restrictions. This finding suggests that the primary violators are being cited for their violations but that their water usage behavior is not being affected enough to decrease usage. This lack of an effect could be attributed to the small fine for violating the policy. When directly comparing cited violators to uncited homes, a consistent pattern was found. Cited violators had greater usage during each of the seasons compared to uncited homes. The volume used and percentage difference between twice a week and once a week irrigation restrictions for cited violators relative to uncited homes provide evidence that a disproportionate amount of the total water used within the study area. The results of this study depict an apparent disregard for the restrictions set forth by Tampa’s City Council. This disregard for the rules may be a product of many factors relating to enforcement, contradictory policies, and the culture of normative landscape practices. With regard to enforcement, the city does not have the financial or human resources needed to prosecute all violators. Therefore, it is highly debatable whether Council Members can adequately enforce these restrictions (Houck, 2002). There are two primary complications regarding enforcement: the delay in action subsequent to the violation and insufficient economic penalties to recoup enforcement expenditures (Houck, 2002). The cited violators included in this study were the greatest users of water resources, on average. Nevertheless, their usage behavior did not significantly change when the restrictions transitioned to a more stringent regime. Perhaps the violators simply weighed the options of either paying a minimal citation fee or risking having to replace costly landscaping. Not only is the penalty paid insufficient to change violator behavior, but also is insufficient to recoup the cost of the enforcement mechanism. The low fine for violating irrigation restrictions creates an atmosphere where the cited
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violator prefers to pay the fine rather than adhere to the restrictions (Alsharif, 2010). With regard to the contradictory policies, the ordinances produced by the City of Tampa create a major dilemma for homeowners that are bound by homeowner association standards that essentially promote non-adherence to irrigation restrictions. There is a perceived and measured association between well-maintained monocultured landscapes and property values, with which homeowner associations are concerned (Laverne and Windson-Geildeman, 2003). Many homeowner associations require groundcover that requires high water input to maintain an esthetically pleasing appearance, and most species of turfgrass require two or three scheduled irrigations a week to maintain their quality during the summer months (Trenholm et al., 2002). Tampa’s ordinances restricted watering to one or two times a week during the study period, with no regard for landscape watering requirements. This presents homeowners with a dilemma regarding whether to adhere to irrigation restrictions. The fine for violating any water restriction, per Tampa Code 26-97, is $100 for the first offense, $200 for the second offense, and $450 and a mandatory court appearance for the third and any subsequent offences. These appear to be monetary penalties that would promote adherence to the restrictions. Nevertheless, the cost for replacing 1000 square feet of turfgrass ranges from $300 to $1000, depending on the species of turf and whether the homeowner has the physical ability to perform the laborious task of installation. This estimated cost does not include the price of the irrigation needed to establish the lawn, which currently is not restricted by Tampa ordinances. The enforcement of the restrictions is also bound by time. Violators of the ordinances can water their lawn seven days a week if the homeowner sets their automated irrigation system to operate in the middle of the night when irrigation compliance officers are not available. With regard to lawn culture, research suggests that people associate well-maintained landscapes with high home values and community connectivity (Robbins et al., 2001). Researchers also contend that the aspiration to sustain one’s yard may be motivated in part by the desire for neighborhood solidarity and/or conflict avoidance (Hirsch and Baxter, 2009). Therefore, residents may perceive compliance with water restrictions as a sign of neighborhood degradation, and thus attempt to avoid conflicts with neighbors by maintaining normative yard care standards (Hirsch and Baxter, 2009). Arguably, the lawn’s greatest role in the social process is ideological; it supports a set of concepts and standards about the way a society should be organized (Feagan and Ripmeester, 2001). The multiple dynamics of lax enforcement, contradictory policies, and the general culture of normative landscape practices provide clear disincentives for compliance with irrigation restrictions. Further research should focus on determining the relationship between parcel size, home size, and domestic water usage. This research could provide useful information for understanding whether water use increases proportionately with parcel size and could help determine whether the size of the home or the size of the lot, has a significant relationship with water usage. Examining the relationship between home value as a proxy for income level and water usage within Tampa communities would also provide valuable information about the socioeconomic factors that could lead to increased water usage. Qualitative research regarding water restriction adherence and knowledge could be another avenue for exploration to provide a further understanding of the reasons and rationales for compliance and non-compliance with irrigation restrictions. This study makes several assumptions regarding individual behavior and the reasons
for non-compliance with the restrictions. The effects of community solidarity, conflict avoidance, and conflicts between local policy and binding community rules could be more effectively measured through a qualitative study, such as, one based on primary data from surveys or interviews. References Alsharif, K., 2010. Construction and stormwater pollution: policy, violations, and penalties. Land Use Policy 27, 612–616. Brennan, D., Tapsuwan, S., Ingram, G., 2007. The welfare costs of urban outdoor water restrictions. Australian Journal of Agricultural and Resource Economics 51, 243–261. City of Tampa, 2009. Water Use Restrictions (04.10.09) http://www.tampagov.net/ dept water/information resources/restrictions/ Dandy, G., 1992. Assessing the economic cost of restrictions on outdoor water use. Water Resources Research 28, 1759–1766. ESRI, 2008. Arc News Online (03.11.10) http://www.esri.com/news/arcnews/ winter0809articles/tampa-bay-water.html Feagan, R., Ripmeester, M., 2001. Reading private green space: competing geographic identities at the level of the lawn. Philosophy and Geography 4, 79–95. Grafton, R.Q., Ward, M.B., 2008. Prices versus rationing: Marshallian surplus and mandatory water restrictions. Economic Record 84, S57–S65. Haley, M.B., Dukes, M.D., Davis, S., Shedd, M., Lailhacar, B.C., 2010. Energy Efficient Homes: The Irrigation System. University of Florida Publication, Gainesville, FL, FCS3274. Haley, M.B., Dukes, M.D., Miller, G.L., 2007. Residential irrigation water use in central Florida. Journal of Irrigation and Drainage Engineering 133, 427–434. Hillsborough County, 2010. About the County (03.11.10) http://www. hillsboroughcounty.org/about/ Hirsch, R., Baxter, J., 2009. The look of the lawn: pesticide policy preference and health-risk perception. Environment and Planning C: Government and Policy 27, 468–490. Houck, O., 2002. The Clean Water Act TMDL Program: Law, Policy, and Implementation. Environmental Law Institute, Washington, DC, pp. 179–180. Hunter’s Green Community Association, Inc., 2012. Lawn Maintenance Guide(15.04.12) http://www.huntersgreen.com/pdf/Rules Regulations/ lines Lawn Maintenance Guidelines.pdf Kenney, D.S., Klein, R.A., Clark, M.P., 2004. Use and effectiveness of municipal water restrictions during drought in Colorado. Journal of the American Water Resources Association 40, 77–87. Laverne, R.J., Windson-Geildeman, K., 2003. The influence of trees and landscaping on rental rates at office buildings. Journal of Arboriculture 29, 281–290. Lund, J.R., 1995. Drought water rationing and transferable rations. Journal of Water Resources Planning and Management 121, 429–437. Mayer, P.W., D’Oreo, W.B., Opitz, E.M., Kiefer, J.C., Davis, W.Y., Dziegielewski, B., Nelson, J.O., 1999. Residential End Uses of Water. AWWA Research Foundation, Denver, CO. McCready, M.S., Dukes, M.D., Miller, G.L., 2009. Water conservation potential of smart irrigation controllers on St. Augustine grass. Agricultural Water Management 96, 1623–1632. Mercer, L.J., Morgan, W.D., 1989. Welfare effects of alternative water rationing schemes: a case study. Water Resource Bulletin 25, 203–210. Nagel, S.S., 1990. Bridging theory and practice in policy/program evaluation. Evaluation and Program Planning 13, 275–283. Nelson, J.O., 1979. Northern California rationing lessons. In: Conference on Water Conservation Needs and Implementing Strategies, Franklin Pierce College, Rindge, NH, July 9–13, 1979, pp. 139–146. Pereira, L.S., Theib, O., Abdelaziz, Z., 2002. Irrigation management under water scarcity. Agricultural Water Management 57, 175–206. Renwick, M.E., Archibald, S.O., 1998. Demand side management policies for residential water use: who bears the conservation burden? Land Economics 74, 343–359. Robbins, P., Birkenholtz, T., 2003. Turfgrass revolution: measuring the expansion of the American lawn. Land Use Policy 20, 181–194. Robbins, P., Polderman, A., Trevor, B., 2001. Lawns and toxins: an ecology of the city. Cities 18, 369–380. SWFWMD, 2009. Water Restrictions (04.10.09) http://www.swfwmd.state.fl.us/ conservation/restrictions/swfwmd.html Timmins, C., 2003. Demand-side technology standards under inefficient pricing regimes. Environmental Resource Economics 26, 107–124. Trenholm, L.E., Gilman, E.F., Knox, G.W., Black, R.J., 2002. Fertilization and Irrigation Needs for Florida Lawns and Landscapes. University of Florida Publication, Gainesville, FL, ENH860. Trenholm, L.E., Cisar, J.L., Unruh, J.B., 1991. St. Augustine Grass for Florida Lawns. University of Florida Publication, Gainesville, FL, ENH5. U.S. Census Bureau, 2011. Quick Facts (12.04.11) http://quickfacts.census.gov/ qfd/states/12000.html West Meadows Property Owners Association, Inc., 2012. Sod Alternatives Approved for West Meadows (12.04.12) http://www.west-meadows.org/ rulesandregulations/lawns.html.