Residential Stormwater Quality Evaluation. Tampa Bay Estuary Program

Transcription

1 Residential Stormwater Quality Evaluation Project Update and Preliminary Results Tampa Bay Estuary Program June 13, 2014

2 Overview Research Design Study Questions Methods Preliminary Results

3 Lawn as a Nitrogen Sink Raciti et al (2008) used 15N tracer applied at a rate of 96 kg N/ha (2 lbs/1000 ft2) to find N retention in lawns high in soil organic matter and biomass. Disturbed soils more readily accumulate carbon and nitrogen Lawns readily take up labile sources of N in lieu of more recalcitrant mineral sources. How long can lawns continue to sequester high inputs of N?

4 That uncouples over time Three years after tracer application, 32 37% of 15N-labeled fertilizer in the soil organic, 25 years later 12-15% still there (Sebilo et al 2013). Mitigation or restoration measures must take into account the delay resulting from legacies of past applications of synthetic fertilizers in agricultural systems.

5 Evaluating phosphorus trends (Lehman et al, 2008, 2009, 2011) Two years of baseline data used to conduct a power analysis to measure changes greater than natural variability Project that a 25% reduction in SRP will take 8 yrs of weekly samples, 2 years for TP, and 3 years for DP. Projected a 20% decrease in DP resulting from ordinance With good baseline data even relatively modest (25%) changes in nutrient load can be detected against background. Significantly lower levels of DP from June - September

6 Nitrogen inputs from Residential Lawn Care Law et al 2004 examined household actions and soil characteristics in two developments Higher application rates associated with new developments (2.2 lbsn.1000 sf) Older developments had higher C and N content 53% of total N from lawn fertilization

7 HOA Residents Fertilize More Wekiva Data (n = 740) Non-HOA HOA Mean Fertilizer Frequency**** Irrigation Frequency Monthly days working in yard* Frequency Fertilize the lawn**** 66% 92% Hire Professional (PLM)**** 35% 65% In-ground automatic irrigation**** 52% 88% Irrigation system on automatic** 44% 65% Change irrigation seasonally** 87% 77% Watering schedule varies* 57% 49% Neighbor's yard influential** 20% 31% T-test and chi-square reported, * = p <.05, ** p<.01 *** p<.0001

8 Even if Holding Professional and Home Age Constant Number of times fertilizer applied in the last 12 months (n=621) Model 1 Model2 Model 3 F-statistic **** **** **** r β t β t β t Professional Fertilizes.46 **** **** **** House Built (yr).18 **** ** 3.32 HOA resident.09 * 2.15 Wekiva Data (n=740) Stepwise linear regression

9 Statewide Socio-demographic Predictors Predictors Maintenance Intensity Property acres Property Acres -.153** House age Years in house Years in Florida HOA Active Income Ed House Age -.249**** Years in house ****.486**** Years in FL -.102**.209****.338****.533**** HOA Active.256**** **** -.195**** Income.246**** **** * Education.108** -.182**** **** Env. Education * **** Florida Home Owners Statewide Dataset, YR 2011 (n=939)

10 Predicting Maintenance Intensity Predictors Model 1 Model2 Standardized Coefficients β p β p Constant Community Norm is High Maintenance Personal Norm Awareness of Consequences Enjoy Gardening Lawn Maintenance Inexpensive Perceived Behavioral Controls HOA Influence House Age (Years) Household Income ($1000) Professional applied products No one applied products R F Statistic 22.12**** 59.09**** Florida Home Owners Statewide Dataset, yr 2011 (n=939)

11 Residential Stormwater Quality Study Objective & Significance Identify ecological and socio-economic factors influencing nutrients in receiving waters in communities where different fertilizer interventions are in place Measure and compare average inputs of N in lbs/area Measure and compare residential landscape management practices and knowledge Estimate residential fertilizer inputs to the community nutrient budget Measure nutrient concentrations in stormwater runoff and surface waters throughout the year

12 Project Partners Tom Ash Environmental Protection Commission of Hillsborough County Kelli Hammer Levy Pinellas County Department of Environment & Infrastructure Rob Brown Manatee County Natural Resources Department John McGee Hillsborough County Public Works Department John Ryan Sarasota County Environmental Services Greg Blanchard Manatee County Environmental Protection Division Heather Maggio City of Tampa Felicia Burks U.S. Environmental Protection Agency Region 4 Ed Sherwood Tampa Bay Estuary Program Project Manager Dr. Paul Monaghan University of Florida IFAS Charles Kovach Florida DEP Southwest District

13 Study Questions RQ1: Are there significant differences in residential nutrient fertilization practices between residents in Pinellas, Hillsborough & Manatee counties? RQ2: Are there significant differences in nutrient dynamics between water bodies receiving stormwater inputs from residential landscapes in Pinellas, Hillsborough & Manatee counties? (1. Supported by Kaye et al 2006, Lockaby et al 2005, Baker et al 2001)

14 Additional Ad Hoc Questions Are there differences in residential nutrient fertilization practices between residents in the higher and lower socioeconomic communities within Pinellas County? Are there differences in nutrient dynamics between water bodies receiving stormwater inputs from the higher and lower socioeconomic communities within Pinellas County?

15 Important reminders This is not a controlled experiment: no cause-effect relationships are proved or disproved No direct testing of ordinance impacts on water quality, due to lack of replication and controls (1 control only) Differences within counties could be greater than across counties with the sample size of 1 to 2 Objectives: setup a project with a methodology to track long-term trends in nutrient dynamics in a real-life experimental setting

16 Current Project Status Social Sampling Representative Telephone Survey of 3 counties (n=835) Door-to-Door Interviews of 4 communities (n=81) Professional Interviews (n=6 of 31 attempted) Analysis and Interpretation Environmental Monitoring 18 surface sampling events completed (total 72) 9-11 storm events collected (total 40) Standard Laboratory Analysis Isotope Analysis Interpretation

17 Which Communities? Control Variables Landscape management practices (Mixed management preferred) Biological, geographic, and geological features Drainage areas and general hydrology HOA presence Housing demographics such as age of development, lot size, and density Absence of golf course No reuse water used for irrigation No septic onsite

18 Study Area Selection Treatment Variables Jurisdictional Boundaries (3 counties) Different Behavioral Differences, Educational Interventions and Ordinances Temporal differences (seasonal) Additional Comparison within Pinellas County: Same jurisdiction Same Educational Intervention and Ordinances Different Housing Demographics (high versus medium Different Behavioral Differences, Educational Interventions and Ordinances Temporal differences (seasonal)

19 Which Communities? P201 Higher Socioeconomic Level Overview

20 Which Communities? P201 Storm Sampling Location

21 Which Communities? P202 Lower (medium) Socioeconomic Level Overview

22 Which Communities? P202 - Storm Sampling Location

23 H101 Overview Which Communities?

24 Which Communities? H101 - Storm Sampling Location

25 M101 Overview Which Communities?

26 Which Communities? M101 - Storm Sampling Location

27 Community Characteristics Jurisdiction Pinellas Pinellas Manatee Hillsborough Subdivision name P202 P201 M101 H101 Have HOA Yes Yes Yes Yes Unit Density/Acre Mean Year Built Irrigated w/reclaimed No No No No Avg. Property Value (2014) $166,017 $313,259 $110,253 $170,137 Golf course presence No No No No HOA self maintained No No No No Average lot size Average built area U/A (sq. ft) Irrigation Source City City City Community Well

28 Social Research Objectives Understand residential landscape management and fertilizer practices Measure fertilizer ordinance awareness Are there differences in nutrient fertilization practices between residents in Hillsborough, Manatee & Pinellas counties? (1. Supported by Kaye et al 2006, Lockaby et al 2005, Baker et al 2001)

29 Telephone Survey Door to Door Interviews Professional Interviews Data Collection

30 Telephone Survey Conducted by the UCF Institute for Social and Behavioral Science 30 Questions/ ~ 12 minutes 835 completions Hillsborough, 292 Manatee, 257 Pinellas Expect 95% C.I. +/- 5.5% Use ANOVA to compare respondents in three counties

31 Survey Respondents Hillsborough Pinellas Manatee Survey Respondents Census Survey Respondents Census Survey Respondents Census Female 59% 51% 61% 52% 62% 51% Caucasian 80% 75% 91% 84% 90% 84% B.S. degree or higher 42% 29% 44% 27% 50% 26% Employed 46% 62% 38% 56% 37% 54% Median age Average Income $76,878 $68,169 $69,010 $63,210 $74,999 $65,746 Number 286 1,167, , ,011

32 Fertilizer Frequency Number of times fertilizer applied in last 12 months Telephone Survey Homeowner Interviews County N Mean Site N Mean Hillsborough H Manatee M P Pinellas P Total

33 Who applies fertilizer? Homeowner Professional No one n Hillsborough 23% 38% 39% 273 Pinellas 23% 32% 45% 240 Manatee 21% 43% 36% 280 Total 793

34 Months Fertilizer Used (%) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec N Hillsborough Pinellas Manatee Important to note that we didn t investigate WHAT was being applied

35 Situations for Non-Fertilizing Are there times or situations when you should NOT fertilize your lawn? Hillsborough Pinellas Manatee During a drought Right before a hard rain* Summer* After a hard rain Winter Fall Morning Evening Spring Not sure* N = 474, *p <.01, % reported

36 Ordinance Awareness Hillsborough Pinellas Manatee Do the ordinances Restrict the use of lawn fertilizer during the rainy season? 75% 75% 66% Restrict the sale of lawn fertilizer during certain months?* 62% 79% 51% Reduce the amount of phosphorous ( P ) allowed in lawn fertilizer? 65% 77% 69% Reduce the amount of nitrogen ( N ) allowed in lawn fertilizer? 58% 62% 66% Require training for professional landscaping companies? 57% 52% 45% N = 188 * p <.001 Pinellas County residents were significantly more likely (43%, p <.0001) to respond that they had heard about government regulations concerning residential fertilizer use than either Hillsborough or Manatee (both 26%).

37 Where residents heard about the ordinance T.V./Newspaper % Landscape Company % Radio % Website % Hardware store/home improvement % Neighbor/Family % Government office % UF/IFAS Extension % Community newsletter % Utility insert % Event/Club % Place of employment % Billboard, Church, Community group, Fertilizer bag, Fire station, Flyer, HOA, Library, Magazine 1 each 3.24% Total %

38 Fertilizer Application Scheduled? County Regular Schedule Only as needed n Hillsborough 66% 34% 161 Pinellas 61% 39% 125 Manatee 71% 29% 170

39 Fertilizer Frequency Countywide County Hillsborough* Pinellas* Manatee Total N Fertilizer Frequency SD Mean reported * ANOVA significant difference at p <.05

40 CL4 Homeowner Interviews Community Number Age Female Caucasian H % 68% M % 73% P % 71% P % 90% Total 81

41 Slide 40 CL4 Add more slides here specific to the interviews Claudia Listopad, 5/20/2014

42 Fertilizer Frequency Interviews Number of times fertilizer applied in last 12 months Countywide Telephone Survey Community Homeowner Interviews County N Mean Site N Mean Hillsborough H Manatee M Pinellas Total P P All 4 Sites

43 Water Quality Sampling Objectives Understand nutrient concentrations entering storm system Relate landscape nutrient inputs with water quality Recommend long-term monitoring that can inform predictive models Address RQ2 : Are there differences in nutrient dynamics between water bodies receiving stormwater inputs from residential landscapes

44 Environmental Sampling QAPP approved by EPA on August 2012 Conducted by ECT (Surface and Storm) and UCF (Soils & Irrigation) Pond Sampling (Surface Water grabs): 18 monthly events per community Stormwater Sampling (flow-paced sampling): 40 samples total (9-11 per community) Soil Sampling: 10 yards per community, 1 sampling event (Summer 2013) CL6 Irrigation Sampling: 3 samples per community, 1 sampling event (September 2013) Samples analyzed for standard parameters (PACE) and isotopes (UGA and NAU)

45 Slide 43 CL6 I wasn't sure when it occurred, I don't have dates in any of the datasheets Claudia Listopad, 5/21/2014

46 Soils by Location Analyte H101 M101 P201 P202 NOx N Mean (mg/kg)* NH4 Mean (mg/kg) Org. Matter (%)* TKN Mean (mg/kg)* P Mean (mg/kg)** EC Mean (ds/m) ph Mean House Age Mean (yrs) Property Value ($) 170, , , ,017 Fertilizer Frequency * ANOVA or Kruskal-Wallis significant difference at p <.05 ** Borderline non-significance (p=0.05)

47 Soils By Landscaper Type Analyte N=9 N=15 N=16 No One Homeowner Professional N=9 N=15 N=16 NOx-N (mg/kg) NH4 (mg/kg) OrgMatter (%) TKN (mg/kg) Phosphorus (mg/kg) Ec (ds/m) ph

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