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1 REPORTED COSTS AND EXPERIENCED ABOUT LOW IMPACT DEVELOPMENT (LID) STORMWATER TREATMENT METHODS IN FLORIDA By DANIEL C PENNIMAN A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE UNIVERSITY OF FLORIDA 2012
2 2012 DANIEL C. PENNIMAN
3 To all the people that have motivated me in this world to pursue my passions both big and small, espec ially my mom
4 ACKNOWLEDGMENTS I would like to acknow ledge Mark Hostetler for advising me through my program and providing me many opportunities along the way. I would also like to acknowledge my committee and David Glunt for the guidance, great ideas and assistance with my thesis project. Thanks go out to my wonderful f amily for the love and support in everything I do and to Ron Ballatore for feeding m e throughout my m aster egree.
5 TABLE OF CONTENTS p age ACKNOWLEDG MENTS ................................ ................................ ................................ .. 4 LIST OF TABLES ................................ ................................ ................................ ............ 6 LIST OF FIGURES ................................ ................................ ................................ .......... 7 LIST OF ABBREVIATIONS ................................ ................................ ............................. 8 ABSTRACT ................................ ................................ ................................ ..................... 9 CHAPTER 1 LITERATURE REVIEW OF STORMWATER TREATMENT SYSTEMS ................. 11 The Economics of LID ................................ ................................ ............................. 14 Barrier Research ................................ ................................ ................................ ..... 15 Cost Comparative Research ................................ ................................ ................... 17 2 REPORTED COSTS ................................ ................................ ............................... 22 Introduction ................................ ................................ ................................ ............. 22 Methods ................................ ................................ ................................ .................. 26 Results ................................ ................................ ................................ .................... 28 Online Survey ................................ ................................ ................................ ... 28 Summary ................................ ............ 30 Central Florida Residential Project, Lake County ................................ ....... 31 Central Florida Corporate Center, Seminole County ................................ .. 31 North Central Florida, Newberry ................................ ................................ 32 Roadway Project, Bradenton ................................ ................................ ..... 33 Florida Aqu arium, Tampa ................................ ................................ ........... 34 Discussion ................................ ................................ ................................ .............. 35 APPENDIX A CALL SCRIPT ................................ ................................ ................................ ......... 47 B SURVE Y ................................ ................................ ................................ ................. 49 C COST QUESTIONNAIRE ................................ ................................ ....................... 53 LIST OF REFERENCES ................................ ................................ ............................... 58 BIOGRAPHICAL SKETCH ................................ ................................ ............................ 62
6 LIST OF TABLES Table p age 1 1 A partial summary of cost comparisons between conventional and low impact development project designs reporte d by the US Environmental Protection Agency (2007) ................................ ................................ ................................ .... 21 2 1 on why low impact development costs more, less, or is variable compared to conventional stormwater management. ................................ .............................. 44 2 2 Summary of total cost savings associated with a low impact development approach compared to a conventional approach for five Florida cas e studies. .. 45 2 3 A summary of low impact development practices employed in the 5 Florida case studies. ................................ ................................ ................................ ....... 46
7 LIST OF FIGURES Figure p age 2 1 Percent of total responses from design professionals concerning perceptions on the primary barriers to using low impac t development in Florida ................... 42 2 2 development compared to conventional stormwater manage ment in Florida projects ................................ ................................ ................................ ............... 43
8 LIST OF ABBREVIATION S ADA Alternative Development Approach BMP Best Management Practice ERP Environmental Resource Permit LID Low Impact Development SWM Stormwater Management SWMF Stormwater Management Facility TMDL Total Maximum Daily Load WMD Water Management Districts
9 Abstract of Thesis Presented to the Gradu ate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Science REPORTED COSTS AND EXPERIENCED ABOUT LOW IMPACT DEVELOPMENT (LID) STORMWATER TREATMENT MET HODS IN FLORIDA By Daniel C Penniman August 2012 Chair: Mark Hostetler Major: Interdisciplinary Ecology Low impact d evelopment (LID) is a green infrastructure stormwater management (SWM) method that has been studied and found to help decrease runoff a nd associated non point source pollution issues. Although LID has begun to gain traction in Florida, most private pr actitioners have not adopted it; one main reason is the perception that LID may cost more The objectives of this study are (1) to identify the primary barrier s for design professionals that have attempt ed to implement LID in Florida and (2) to determine the relative capital costs of LID in comparison with the conventional methods for constructing stormwat er treatment systems in Florida. Usin g a snowball sampling method, I identified and interviewed 29 professionals from firms that had knowledge/experience with LID practices. I administered a n online survey about barriers to LID and an associated questionnaire on LID versus conventional cost s f or actual stormwater design projects Participants reported that costs associated with LID were a barrier, but the permitting process was the main barrier hindering the consideration and use of LID methods in Florida. Overall 41% of respondents thought LI D was more
10 expensive than conventional methods 32 % thought it was less expensive and 27 % could not give a definitive answer as to whether they beli eved LID to be more or less expe nsive. The latter group thought the relative cost of LID is dependent on th e permitting process, site conditions and which particular LID tools were used in the design. For the five projects collected, the LID design option (compared to a conventional design) had a capital cost savings that ranged from $294 ,000 to $2,925,000 for stormwater management. Variation in cost savings was primarily due to the types of LID features used in the stormwater treatment system and site conditions Results indicate that practitioners need to be well experienced with LID to realize possible signi ficant cost savings I n order to encourage LID Florida stormwater regulators should focus their attention on smoothing the permitting process and accepting properly designed LID stormwater management options
11 CHAPTER 1 LITERATURE REVIEW OF STORMWATER TREATMENT SYSTEMS In the United States more than one million acres of land are developed each year and much of this is transferred into roads, parking lots, and other surfaces which are impermeable to precipitation. A great deal of research has been done t hat concludes water quality greatly declines in aquatic systems/resources when the impermeable areas of a watershed exceed 10% due to increases in stormwater runoff (Center for Watershed Protection 1998). The management of stormwater with a focus on water quality outcomes is a fairly recent practice. Historically urban stormwater runoff was almost entirely thought of as a quantity problem (flooding) with the solution being rapid draining into sewers, centralized ponds or directly into natural receiving b odies of water ( Heaney 2012, Rushton 2001 Civic Federation 2007 Merriam 2011) S tormwater runoff lo ads often carry urban contaminants such as automobile oils, fertilizers /pesticides heavy metals and pet wastes (Macmullen and Reich 2007, Clark and Acomb 2008, USEPA 2003). The National Water Quality Inventory found that urban runoff is the main cause for impairment to studied estuaries and the third highest cause of impairment to i nventoried lakes (USEPA 2003). In Florida, research has shown since the 1970 than half the pollutant loads inundating the s point, stormwater sources (Rushton n.d., Livingston and McCarron n.d. ). T he dominant method for managing stormwater involved construction of large conv eyance system s made up of concrete curbs, gutters, and pipe systems intended to transport water running off impervious surfaces directly into natural receiving waters In accordance with the 1987 Clean Water Act (CWA) and associated state stormwater manag ement plans, some regulations required the use of
12 best management practices ( BMPs ) in order to improve the stormwater runoff quality before re entering natural systems Florida was particularly ahead of the curve in adopting stormwater regul ations which relied mostly on pipe and pond management practices to control, store, and treat stormwater runoff in centralized retention ponds ( Merriam 2011, personal communication, Mark Clark, personal communication, June 11 2012 ) However, much of the po llutant removal efficiencies developed for conventional BMPs were based on sediment removal/settling rates and r esearch indicates that they have been over credited for mitigating water quality impacts and oft en do not meet assumed pollutant removal levels ( Harper and Baker 2007 Kloss and Calaru see 2006 ) Therefore, compliance with current stormwater permits often does not ass ure the results of surface water protection/restoration goals Also, Centralized pipe and pond conveyance systems have been associate d with negative impacts such as bank and channel erosion and impairment of aquatic habitats. Environmental degradation of water resources wh en aquatic systems are n o longer suitable for fishing, recreating or drinking A rel atively new pra ctice used to treat stormwater, known as l ow impact d evelopment (LID), focuses on maintaining the pre development hydrologic function of the area and managing stormwater in ways closer to the natural rainfall runoff cycle ( unty 1999, USEPA 2000 Po well et al. 2005 ). LID strategies manage stormwater in three main ways. The first is through decentralized storage in which stormwater is contained on a temporary or permanent basis. The second is infiltration in which the water is encouraged to enter the soil to be treated through biophysical processes. The third is through evapotranspiration which moves water to
13 the air from the soil, plants, and the built environment. Some LID tools only perform a single one of these beneficial f unctions, whereas others can perform all three (MMSD 2010). Research on the functional capabilities of LID to reduce stormwater runoff from developed sites and decrease water pollution has been conducted in the US since the Coffman 200 0 MacM ullen and Reich 2007, Prince George's County 1999 ). I n most cases results indicate that LID performs better than conventional stormwater management (Harper and Baker 2007, Hood et al. 2007 Rushton 2001, USEPA 2000, Willis 2012 ) Additionally, LID adds fl exibility to where and how stormwater management occurs, unlike large, centralized systems ( Kloss and Calarusee 2006 USEPA 2005 ). G reen infrastructure and stormwater management techniques have been widely employed in o ther countries such as Japan, Austra lia, and Germany, but are still fairly infant in the US ( Kloss and Calarusee 2006 ) LID has been termed a couple of different things, especially in older literature before the envelope term low impact development was deemed. Some of these terms synonymous with LID include green infrastructure sustainable urban drainage systems (SUDS), best management pr actices (BMPs), source control natural drainage systems, sustainable stormwater management, and conservation site design (MacMullen and Reich 2007, CRI 200 5 ) LID has been slow to come to Florida for a couple of main reasons. One of the physical conditions are unique from many other areas in which LID practices hav e been well tested Heavy rainfall geology and hydrological ch aracteristics such as high water tables are the most often cited physical conditions which make using LID difficult in Florida. Rese arch and practical knowledge have been instrumental in adapting LID
14 techniques for Florida conditions ( Clark and Acomb 2008, Merriam 20 11). Our research explores what some of the other issues have faced the private development industry and impeded the use of LID. The Economics of LID D evelopers will most likely utilize construction practices which make the greatest economic se nse for their company often with only limited concern for water resource protection (Williams and Wise 2009). While LID may be an appropriate stormwater treatment system to address water quality and runoff issues, concerns have been expressed by private d evelopers about higher costs associated with implementing LID ( Bowman and Thompson 2009 CRI 2005, Macmullen and Reich 2007, Powell et al. 2005). Although this perception is still strong da ta is beginning to show that LID practices can lead to reduced cos ts and other economic benefits ( Kloss and Calarusee 2006 Liptan and Brown 1996, USEPA 2005, USEPA 2007). T he economic benefits of util izing LID go beyond potential construction cost savings. The literature cites benefits that have major economic implicati ons associated with improved air and water quality, decreased urban heat island effect, improved groundwater recharge, and increased aesthetics (CWP 1998, Hubbart 2011, Montalto et al. 2007, Williams and Wise 2009 ). A important note from the literature is the finding that many development companies and municipalities which have realized cost savings from using green infrastructure practices, did so to achieve an environmental goal or because of an environmental ethos, not because of an initial cost analysis ( Civic Federation 2007 Macmullen and Reich 2007 ).
15 Below, I (1 ) outline prior research focused on identifying barriers to using LID nationally, and (2) review cost research which has been done to compare LID and convention al stormwater management Barrie r Research As low impact development practices have become more accepted as an alternative to conventional stormwater management, researchers have attempted to identify factors impeding its use. Due to the unique characteristics of the development enterpri se, which include huge expenses and risks necessitating major financial and time investments most any cited barrier is a concern for the developer because it translates back to cost one way or another. There is inherent uncertainty with the early use of n ot well tested practices su ch as LID which hinders proper consideration for these approaches (Bowman and Thompson 2009 David Glunt, personal communication, 2011 ). Therefore, even if the alternative development approach is estimated t o be the lowest cost o ption developers inexperienced with LID will often choose an approach which is known to achieve revenue goals without necessarily maximizing them ( CRI 2005 Bowman and Thompson 2009). Therefore development companies are inclined to use conventional practi ces, especially in an unfamiliar or tumultuous construction market (Williams and Wise 2009). The Civic Federation (2007) released a report which reviewed and summarized the main issues with attempting to implement LID projects for five U.S. local governmen ts. One of the major findings was that the decentralized nature of LID creates some major difficulties. Because LID uses a suite of practices which are distributed throughout the landscape questions of funding, and accountability for operation and maintena nce become much more compl ex than for centralized systems.
16 Also, a decentralized approach to stormwater management usually causes design effort to increase compared to conventional systems because the need to model and monitor many stormwater infiltration and storage controls versus one large retention pond (Gordon 2010 Heaney and Sansalone 2012 ) D ue to the infancy of LID in major practice, a lack of knowledge and training on the part of planners and regulators has been another major obstacle for the prog ression and use of LID. Because of LID s heav y reliance on natural processes and systems, the predictability of flood control performance and pollutant removal function of these strategies become s much difficult than with highly engineered centralized syste ms (Heaney and Lee 2006) Real world performance data, technical information, and experience with LID practices will help to alleviate these uncertainties (Civic Federation 2007, Godwin 2008). Because c itizen safety is usually the prime concern of regulato ry bodies, previously mentioned concerns over flood control are one of the major issues which often leads to inflexible development rules (codes, zoning regulations, construction standards and local ordinances) concerning stormwater infrastructure which ne cessitate special permits and variance s t o approve LID practices ( CWP 1998). Combined these issues often i n crease project approval /permitting times which equates to risk and cost for developers ( Bowman and Thompson 2009 Ryan 2006 ). Major challenges to the implementation of LID in Florida were identified by a survey and collected comments from Florida developers, design professionals and government officials who attended workshop s /training programs concerning LID practices (Kipp et al 2011) These practi t i oners ranked
17 as the first and second main challenges of LID features were cited as the thir d overall challenge to LID implementation in Florida Cost Comparative Research R esearch to compare LID and conventional costs is currently limited and preliminary but growing quickly B ecause LID is still a n emerging technology in practice a major portio n of LID cost estimates are not standardized and are largely varied (Sample et al. 2003, CRI 2005). A variety of economic evaluations have been used to quantify and compare its cost to conventional stormwater management These evaluations include estimate d capital cost comparisons life cycle comparisons and cost benefit comparisons ( MacMullen and Reich 2007 Powell et al. 2005 ) One challenge to developing direct cost comparisons is that LID methods are most often used in combination with conventional des ign techniques Therefore an apples to apples, line item comparison is usually not achievable and total project costs must be considered ( CRI 2005). Although direct capital cost comparisons are least favorable for the overall consideration of LID pra ctices development companies favor this type of economic evaluation This is due to the fact that development companies most often sell development projects once they are completed with little consideration for long term costs or benefits of the site. From capi tal cost comparative research o ne of the greatest advantages of LID is that it allows for decr eased spending on pipes, inlet structures, large stormwater ponds, curb and gutters, roadway paving, and clearing and grading. It does so by replacing highly man ufactured, centralized conveyance systems with less material intensive,
18 more natural techniques such as bioswales, rain gardens, and mitigation wetlands ( Coffman 2000 Lehner et al. 2001, CWP 1998, USEPA 2007). Permeable surfaces are arguably the most wide ly used LID tool thus far, and a good example to demonstrate how economies of scale come into play when comparing the costs of LID and conventional centralized stormwater management. C onventional style paving is often $2 5 cheaper per unit (Doug Buch, pers onal communication, December 14, 2011) ; but if designed properly and given accurate storage credits porous/permeable materials can reduce the need for piping and ponds, therefore reducing construction material costs by as much as 30% (CRI 2005). Coffman (2 00 1 ) reports that in favorable conditions, stormwater and site development construction costs can be reduced by 25 30% using LID techniques compared to conventional approaches. Areas where construction costs are often higher for LID projects are plant mate rial, site preparation, soil amendments, and underdrains (USEPA 2007). National Cost Comparative Research : A report released by the US EPA (2007) examined 17 case studies of development projects that included LID tools and compared the costs of using LID t o using conventional stormwater management tools (Table 1 1) The majority of projects identified in this research s howed that LID cost less than conventional development Estimated total capital cost savings ranged from 15 80% in this gr oup of case studie s The reviewed case study which LID realized a much higher cost than the comparable conventional design was because of the use of green roofs which are well documented as being capital cost intensive (MMSD 2010 ). To date US EPA (2007) is the most extensiv e research that examines projects which were actually constructed using a LID approach Although this is true, some of the c ase
19 st udies were modeling studies in which a LID and conventional stormwater design were developed for the same site and costs were estimated and then compared Florida Specific Cost Compa rative Research : A 44 acre residential subdivision in Gainesville, Florida was designed initially using LID in order to better stormwater issues, lower water consumption and increase biodiversity in the area (Acomb 2009) A model home in the subdivision was designed using an extensive suite of LID practices including natural buffers, rain gardens, pervious pavers, soil moisture sensors, minimized turf, native plants, an exfiltration tank, a shared dri veway and others Turf reinforcement was used in some areas of the LID design in order to accommodate guest parking and reduce paving. An in depth capital cost and maintenance cost comparison was performed at the site level for the Madera Model home. It wa s compared to a conventional home and lot in a subdivision nearby which had similar soils and vegetative canopy. The LID overall about $1,500 (7.6%) less expensive compared to the similar sized conventional home/lot design. The bul k of savings associated with the LID approach came from reduced clearing/grading, a shared driveway, and a reduction in the use of turf grass. Increased mulching, the exfiltration tank, and the reinforced turf were line items in which the LID design cost m ore. A qualified landscape maintenance contractor was consulted in order to develop and compare maintenance costs. The LID site realized overall maintenance savings of about $1,900 a year mostly attributed to the reduction of turf and required care. A two year cost modeling study was published in 2009 which used a hypothetical residential neighbo rhood to compar e construction costs and buyer valuation for four alternative approaches to stormwater management and land development in Florida
20 (Wi lliams and Wise 2009). It used cost functions from several sources to tabulate capital construction costs and compare the four scenarios deemed; 1) traditional development, 2) cluster development, 3) partial LID, 4) full LID. The full LID scenario yielded the lowest cons truction costs followed second by the cluster development scenario. The majority of cost savings was due to the decrease in curb and gutter, storm sewer, and sidewalks. A hedonic price model was used to compare buyer valuation for the four scenarios. It wa s found that the full LID option had the highest return on investment (ROI) for the first year of the study but in the second year the cluster alternative had the highest ROI Redevelopment/Retrofit Cost Compar ative Research : The literature shows that LID has been most widely used in new residential developments but it has also proven to be an environmentally and financially smart way to retrofit existing development (USEPA 2000). In the redevelopment or retrofit scenario, LID is used in several different m ain ways The first is in ultra urban settings to control and treat stormwater before it is discharged directly into receiving waterways For this situation, it has been used to reduce the necessary size of, or in some cases, eliminate the need for the add ition of centralized storage ponds in redevelopment projects (Gordon 2010 USEPA 2005 ). LID has also been used to decrease the load and stress on aging stormwater infrastructure. T he decentralized and flexible nature of LID allows for i t to be utilized in stormwater retrofit project plans rang ing from single lot to citywide. Research conducted by city officials in Seattle and Vancouver concluded that using green infrastructure to retrofit locations with existing conventional stormwater management systems wi ll be only
21 marginally more expensive than rehabilitating/fixing the conventional systems ; but they found that it would be less expensive in new developments (Kloss and Calarusse 2006). In Austin, Texas c ity plans focused on buffering streams in order to p rotect the Edwards Aquifer (USEPA 2005) L arge amount s of subdivision runoff was being concentrated and discharged directly into local streams by curb and gutter practices The conventional style, sedimentation filtration, retention pond which would have b een required to manage the runoff would have cost $250,000. Instead of employin g a pipe and pond design, engineers directed the stormwater discharge as sheet flow to a series of shallow biodetention areas before entering the receiving streams. T he redesign was done at a total cost of $65,000, which saved $185,000 compared to the large pond which would have been dug This cost difference does not include savings from reduced drain pipe sizes and trenching. Table 1 1. A p artial summary of cost comparisons bet ween conventional and low impact development project d esigns reported by the US Environmental Protection Agency (2007). Project Conventional Development Cost LID Cost Cost Difference % Difference in Costs 2 nd Avenue SEA Street $868,803 $651,548 $217,255 2 5% Auburn Hills $2,360,385 $1,598,989 $761,396 32% Bellingham City Hall $27,600 $5,600 $22,000 80% Gap Creek $4,620,600 $3,942,100 $678,500 15% Garden Valley $324,400 $260,700 $63,700 20% Ken sington Estates $765,700 $1,502,900 $737,200 96% Laurel Springs $1,654,021 $1,149,552 $504,469 30% M ill Creek $12,510 $9,099 $3,411 27% Prairie Glen $1,004,848 $599,536 $405,312 40% Somerset Subdivision $2,456,843 $1,671,461 $785,382 32% Tellabs Corp. Campus $3,1262,160 $2,700,650 $461,510 15% Bellingham B loeden Donovan Park $52,800 $12,800 $40,000 76%
22 CHAPTER 2 REPORTED COSTS Introduction In the United States more than one million acres of land are developed each year and much of this space is tran sferred into roads, parking lots, and other surfaces which are impermeable to precipitation. These impermeable areas are collectively known as impervious surfaces. Due to symptomatic issue of urbanization, increased stormwater runoff, water quality greatly declines in aquatic systems/resources when the impermeable areas of a watershed exceed 10% (Center for Watershed Protection 1998). Urban areas often consist of 45% or more of impervious surfaces ( Kloss and Calarusee 2006 ). The National Water Quality Inven tory found that urban runoff is the main cause for impairment to studied estuaries and the third highest cause of impairment to inventoried lakes (USEPA 2003). In Florida, stormwater runoff is the major source of pollutants to lakes, estuaries, and streams and has been since the ( FDEP 2008, Livingston and McCarron n.d., Rushton n.d. ). In accordance with the 1987, Clean Water Act (CWA) and associated state stormwater management plans, some regulations required the use of best management practices (BM Ps) in order to improve the stormwater runoff quality before re entering natural systems. Florida was particularly ahead of the curve in adopting stormwater regulations which relied mostly on pipe and pond management practices to control, store, and treat stormwater runoff in centralized retention ponds ( Merriam 2011, personal communication, Mark Clark, personal communication, June 11 2012). Much of on sediment settling ra tes and research indicates that these have been over credited for
23 mitigating water quality issues ( Harper and Baker 2007, Kloss and Calarussee 2006 ) Therefore, compliance with current stormwater permits often does not assure the results of surface water p rotection/restoration goals. Low Impact Development (LID) is a green infrastructure stormwater management method which has been studied and found to help minimize runoff from developed sites and remove most water pollut ants better than conventional method s ( Hood et al. 2007 Rushton 2001, USDOT 1996, USEPA 2000, Willis et al 2012 ) Some other benefits of LID practices include better groundwater recharge, impro ved surface water hydrology, and increased biodiversity ( CWP 1998, CRI 2005) LID fo cuses on mana ging stormwater in smarter ways that maintain or mimic the natural rainfall r unoff cycle ( Civic Federation 2007 Prince George's County 1999 ) LID practices range from structural systems such as permeable paver s to non structural practices such as low imp act landscaping, to site layout design s such as cluster development (also known as conservation design). The tools of LID control and treat stormwater in three main ways. The first is through decentralized storage in which stormwater is contained on a temp orary or permanent basis in shallow, vegetated depressions. The second is infiltration in which the water is encouraged to enter the soil instead of running across impervious surfaces. In some cases infiltration tools can be used to treat stormwater throug h biophysical and filtering processes. The third is through evapotranspiration which moves water to the air from the soil, plants, and the built environment. Some LID tools only perform a single one of these beneficial functions, whereas others can perform all three (MMSD 2010 ).
24 Although LID has begun to gain some traction, the m ajority of private development practitione rs have been slow to adopt LID practices (Merriam 2011). B ecause of inexperience and unknown costs associated with it prac titioners are re luctant to use LID which hinders adequate consideration for these approaches (Bowman and Thompson 2009 David Glunt, personal communication, 2011 ). Due to the unique characteristics of the developmen t enterprise, which include massive expenses and risks ne cessitating major financ ial and capital investments any obstacles or hiccups in the development process translates back to cost one way or another. Therefore the majority of private companies are inclined to use tried and true practices, especially in an unfamiliar or tumultuous construction market ( CRI 2005, Williams and Wise 2009). LID is still a n emerging technology in practice therefore a major portion of LID cost estimates are not standardized and are largely varied ( MacMullen and Reich 2007, Sam ple et al. 2003 ). The most extensive capital cost comparative research to date, USEPA (2007), gives a national view of how using LID can lead to reduced capital costs. In this research 17 case studies were reviewed which compared LID and conventional capi tal construction costs using both built projects and modeling methods A large majority of the examples had lower construction costs with the LID approach and total capital cost savings ranged from 15 80%. Coffman (2000 ) reports that with favorable site co nditions, stormwater management and site development construction costs can be reduced by 25 30% using LID techniques compared to conventional approaches. The s e studies and others show how LID allows for decr eased capital spending on pipes, inlet structu res, large stormwater ponds, curb and gutters, roadway paving, and clearing and grading. It does so by replacing highly manufactured,
25 centralized conveyance systems with less material intensive, and more natural techniques such as bioswales, rain gardens, and mitigation wetlands ( Coffman 2000, CWP 1998, Lehner et al. 2001 Liptan and Brown 1996 ). Areas where construction costs are often reported as being relatively higher for LID projects are plant material, site preparation, soil amendments, and underdrain s (USEPA 2007). E conomic data has been collected from projects mainly in the northwest and northeast US leaving a void of economic data for Florida and other s outheast ern states Practicing design professionals (engineers, architects, landscape architects ) are often tasked with devising early estimates of probable construction costs and finding the most effective methods of achieving a goal in order to minimize overall project costs ( Glenn Acomb, personal communication, Heaney 2012) They also play a large role in the up front, early consideration of unconventional or alternative techniques (David Glunt, personal communication, 2011) Design firms and associated p rofessionals who have attempted to use LID methods in Florida projects are a knowledgeable grou p about the most pert inent issues impeding greater adoption of LID. Identifying what they believe to be the main barriers to LID and their perceptions on the relative costs of LID compared to conventional practices will help identify significant issues a to encourage the use of LID in future development Sampling from knowledgeable practitioners in Florida, our objectives were (1) to identify the primary barrier s for design professionals that have attempt ed to implement LID in Florida and (2) to determine the relative capital costs of LID in comparison with the conventional methods for constructing stormwater treatment systems in Florida.
26 Methods Selection of Participants : A snowball sampling method (Castillo 2009) was used to obtain contacts for design fir ms who have incorporated LID methods in their Florida projects A group of thirty three (33) design firms and associated professionals were obtained and contacted by p hone for an initial interview This interview was partially scripted ( A ppendix A) regardi ng willingness to participate in the research, k nowledge / experience with LID, availability of cost data on LID projects, and references for other firms who have utilized LID in Florida project designs. P rofessionals from the firms were required to be exper ienced with LID and have used two or more LID methods i n a project design within the last three years to be included in the study. Twenty nine (29) of the interviewed firms w e re chosen for the final sample. Survey on Barriers and Perceptions about LI D: A s urvey was designed to collect data from the selected design professionals concerning issues with the use of LID A combination of 13 m ultiple choice and open ended questions were asked on the survey The questions in the survey were developed using a combi nation of information found in a review of the literature and collected responses from the initial conversation with professionals (Appendix B) Demographic questions addressed which Water Management Districts (WMD) the firms submit the most environmental regulatory permits (ERPs ) to. E nvironmental R esource P ermits are the approval method of stormwater management system based on wat er quality and quantity aspects. Demographic questions also addressed how long the firm s ha d been in operation and an estimated number of design projects which incorporate LID. The bulk of the survey focused on obtaining information on the barriers to adoption of LID practices (respondents were asked to select up to three primary barriers they had experienced
27 when trying to use L ID) and perceptions about relative costs of LID stormwater management practices compared to conventional practices Responses to open ended questions were reviewed and summarized to develop generalized categories for the 2) Some open responses included more than one piece of information; therefore they were placed into multiple categories. Firms who indicated using LID in <15% of project desig ns were deemed less experienced and those who used LID in 15% of project designs were experienced. A perception of whether LID costs more or less than conventi onal methods. A value of 0.05 was used. The survey was tested by a focus group of academic and practicing design professionals for content and timing. It was distributed as a link in an email directly to the professionals who agreed to participate Up to four email rem inders and two calls were made concerning the completion of the survey. Twenty two (22) professionals completed the survey Cost Data Questionnaire: Associated with the onl i ne survey, a questionnaire was devised to collect cost data on projects in which bo th a conventio nal and LID design approach were completed for the same development project (Appendix C ) The location, specific site conditions (major soil type and height of water table), LID tools used, and cost data were requested for each case study. Th e questionnaire was primarily designed based on the breakdown of results reported in the USEPA (2007) study on LID costs We sought out total project costs and apportioned cost data on
28 planning/permitting, site grading and preparation, stormwater infrastru cture, paving/surfacing, and maintenance We also i nquired about notable economic benefits associated with the LID projects such as increased buildable space, permit breaks, grants, and incentives. The questionnaire was reviewed and edited by the same focu s group as the survey and given to participants as an email attachment The questionnaire was distributed to design professionals who indicated they had comparative cost data Results Online Survey Of the 22 professionals who completed the survey, 16 were engineers and 6 were landscape architects. Thirty nine percent (39 % ) of respondents had the most experience applying for ERPs in the St. Johns WMD 23% in the Southwest WMD, 13 % in the South WMD, 16 % in the Northwest WMD a nd 9 % in the Suwannee River WMD Most (73%) firms had been in business for 11 or more years Based on the estimated percent of projects designed using LID methods, 12 respondents were deemed experienced, and 1 0 were deemed less experienced. T he primary barrier selected by respondents was approval and permitting issues (33%) H igher costs ranked fourth (12%) close behind issues with operation and/or maintenance (14%) and client disapproval (14%) (Figure 2 1) When directly asked about overall development costs a large portion (4 1 %) of res pondents indicated that LID costs more than conventional methods. Combining the respondents who believed LID to be less and much less expensive 32% perceived LID as a cost effective method of stormwater management (Figure 2 2) In the origi nal survey the re were separate equal and cannot answer categories; these categories were combined due the similar
29 nature of responses in a follow up, open response survey question described later The resul ting combined category yielded 27 % of responses and these profe ssionals could not give a definitive answer be cause they believed the costs of LID were too variable (Figure 2 2 ). Statistical analysis was performed on data for the respondents who gave a definitive answer whether LID costs more or less than conventional practices. A value of relationship between experience level and perceptions on the relative cost of LID compared to conventional methods. Taking this into considera tion, the fact that five of the seven (71%) experienced professionals thought that LID costs less, and seven of the nine (78%) less experienced professionals thought that LID costs more, gives a glimpse that respondents experience level with LID tended to affect perception on the relative costs of LID c ompared to conventional methods. After the question about overall costs of LID, t he participants were given an open response question Based on your answer for Q8, why is LID more or less expensive than con ventional stormwater management techniques ( A ppendix B). The responses to this question were reviewed and summarized to develop categories fo r the pr 1 ) From the responses we believe the participants who ga ve definitive ans wers that LID costs more or less were primarily addressing actual capital costs and were not considering hard to quantify issues like permitting delays. For the sub group of participants who answered that LID costs more they mainly thought it was the int ricate and spread out nature of LID controls requiring more time and effort that caused construction and design costs to make LID overall more
30 expensive. Although operation and maintenance (O&M) was mention ed as a reason for why LID costs more, the engine ers may not be giving proper consideration to the fact that for proper function, conventional systems require far more O&M than they often receive ( Harper and Baker 2007) The respondents w ho answered that LID costs less attributed it to the ability to re duce earthwork for large stormwater ponds, reduce hard infrastructure, and increase buildable space due to smaller/eliminated centralized stormwater m anagement facilities Individual Case s Cost Data and Summary The estimated/cited capital cost figur es in T able 2 2 do not include design costs, labor costs or non pertinent construction costs such as mobilization, maintenance of traffic and utility reworking. The results showed the amount of detailed comparative data was not as fully available as was first indicated from the interviews. All cost comparative data received was supplied by engineers. The five case studies collected indicated an LID design scheme to be the lowest cost option for base stormwater management needs (Table 2 2 ) Each of the pro jects used several different LI D treatment practices (Table 2 3 ). Typically for cost estimates on private projects there is a single, early estimate at the beginning of the project to get a base cost. These are fairly broad, conceptual calculations of the entire design which are used to decide whether or not to move the project forward and acquire the land. While designing municipal projects, engineers must develop more cost estimates in order to establish fees or bond amounts. Engineering firms must calcu late and refine estimates throughout the stages of the design process. Late estimates are submitted over halfway through the design process and most often use historical, line item cost data from similar projects in the area. Late
31 cost estimates compared t o early ones for the same project represent greater precision and incremental changes to site layout/design. Built projects have been designed, permitted, and construction has been completed. Central Florida Residential Project Lake County Stage of Design : e arly Type: new residential Size of Project: 170 acres Major soil type: B Average depth of water table on site: 3 6 feet The conventional design utilized three centralized retention basins whereas the LID design incorporated 26 shallow storage basins. The conventional design required 750,000 cubic yards (CY) of excavation/grading and 14,000 linear feet (LF) of storm pipe, whereas the LID design only required 450,000 CYs of excavation/gradin g and 2,000 LF of storm piping. The LID design was estimated to save $1,000,000 (40%) in excavation costs and about $1,020,000 (92%) in stormwater piping. Additionally, t he LID design maintained much of the hydrological signature and natural ca pital (wetlands and forested areas) of the original land plan which provide d a great deal of the necessary stormwater storage. Overall, t his de sign was able to save approximately 51 acres of green space (includes wetlands, foreste d areas, and other natural space ) and created a walkable community with a high level of recreational sense of place. A pproximate ly half of the green space was e ffectively designed with the dual purpose o f community recreation and dry retention SWM. No development units were lost or gained in the LID design. Central Florida Corporate Center Seminole Cou nty Stage of Design: early Type: New Commercial/Office
32 Size of Project: 28 ac res Major Soil Type: C Seasonal high water table on site: 2 feet The cor porate center is made up of five retail lots, 14 office lots, and one hotel. All requ ired buffers in betwee n lots were used as storage and conveyance swales which eliminated the need for any on site dry retention ponds. This incr eased the buildable space by approximately 10% per lot. The largest cost savings came from reduced need for excavation and grading, an d the second largest savings came from a decreased need for piping and structures. The majority of dry retention areas double as parks and open space for community recreation. A vegetated pond was incorporated into the plan for attenuation flow but was des igned to be very infrequent ly used The increased buildable space per lot allowed for an additional one to two lots compared to the conventional design. Design plans have been approved, but construction has not begun yet. North Central Florida Newberry St age of Design: early Type: mixed residential/commercial Size of Project: 250 acres Major Soil Type: A Average depth of water table on site: 10+ feet This project was originally designed using conventional pipe and pond techniques which required 34 acres o f space for retention ponds throughout the property. The pond space in the conventional design held no recreation or community value other than the control and retention of stormwater. An LID based re engineering proposal was performed for the project desi gn which utilized existing wetlands for digressional storage of pre treated (through LID practices ) stormwater. The major savings came from
33 $1,225,000 in reduced excavation/grading and $1,700,000 in reduced stormwater structures (gutters, piping, etc.) Th e LID design preserved 55 acres of open/green space, which i ncluded 100% of the old growth h ammock (~8.67 acres) on the property. Thirty seven of the 55 acres were effectively designed with the dual use of recreation and stormwater detention. The design al lowed for a walkable community, with combines dry detention areas, with linear pathways). No development units were lost or gained in the LID design. Road way Project Bra denton Stage of Design: late Type: roadway redevelopment Size of Project: 1.25 miles Seasonal High Water Table on site: 1 2 feet On this site t he stormwater from the section of roadway currently discharges directly into nearby Whitaker Bayou with no treat ment or control (a drainage system) Due to current Southwest Florida WMD stormwater r ules the roadway improvement triggered regulations which require the treatment of runoff from the site. In 2 008, t he red evelopment project was designe d using conventional pipe and pond practices. Land availability space was extremely limited for this type of system and a major utility relocation (not included in the compared costs) was required for the large storm sewer necessary in this design. In 2010 an LID design was used to eliminate the need fo r the large retention pond and hel p reduce the cost by more than one million dollars. The LID design allowed for a reduction in excavation and grading costs of $72,130. Both the conventional and LID designs were 60% complete at the time of the
34 cost estimates but the project did not make it to construction because the proposal was still deemed too costly for the city Florida Aquarium Tampa Stage of Design: built Type: parking lot redevelopment Size of Projec t: 11.25 acres This project was originally designed using conventional me thods of stormwater management. The project was re engineered utilizing LID elements as a demonstration site for the beneficial effects of sustainable design elements on stormwater r unoff quan tity and quality. The money saved from reduced curbing and piping was used for re invested for landscaping in the bioswales and rain gardens and the addition of pervious concrete For base stormwater management needs the LID option allowed a 19% The addition of natural system improvement such as enhanced landscaping low volume irrigation, and shoreline improvements to Ybor C hannel added $275,000 to the base LID stormwater management cost. Adding p ervious pavement to the parking areas cost an additional $268,000 to the base LID costs. With enhancements the LID option cost about 11% more than the conventional design. The additional expenses over the initial budget were funded by grants from United St ates Environmental Protection Agency F lorida D epartment of E nvironmental P rotection and Southwest WMD. The site has been a model example of the benefits of alternative stormwater methodologies because it allowed for a unique experimental opportunity whic h compared pollutant loads associated with LID (porous paving with a swale) practices to conventional (asphalt paving with no swale) practices When sampling was performed post construction t he
35 LID design saw a 42% load reduction in total Nitrogen, a 3% re duction in total Phosphorus and a 91% reduction in suspended solids compa red to the conventional design (Rushton 2001 USEPA 2000 ) Discussion Design practitioners indicated that project approvals/permitting was the largest barrier impeding the use of LID in Florida and higher LID costs was a secondary concern. This finding was similar to a recent survey of practitioners concerning LID adoption in Florida ( Kipp et al. 2011) In this study, researchers surveyed and collected comments from a large sample Flor ida developers, design professionals, and government officials who attended training programs concerning LID practices. They found that insufficient and/or unclear LID design and approval criteria was ranked as the overall most critical challenge to using LID and economic and cost factors regarding LID was ranked third Approval through regulatory agencies is crucial as any delays in the design or permit process equates to risk and cost for developers and greatly discourages up front consideration and imple mentation of LID (Ryan 2006). To design and present a LID stormwater treatment plan is very costly and if there is a perception that it would not be permitted, the LID project would likely never be considered within the design firm. These findings combined make a clear argument that the removal of regulatory barriers must be the center focus in order to encourage LID. presence of five semi independent water management districts, all having their own permitting requirements, seems to be a recipe for disaster in attempting to smooth out regulatory issues on stormwater management (Merriam 2011). Instead, we believe this presents an opportunity to encourage LID adopti on. The regional natu re of the five
36 WMDs enhances specialized knowledge of the physical conditions and the most pertinent water quality issues within their specific district (Cammie Dewey, personal communication, May 29, 2012) In order to reduce risk and confusion for develop ers the WMDs r e gulations concerning LID should focus on design standards for specific tools prime for the regional conditions of the state and for the water quality goals of the area In the sand dominated soils of the state, mostly the south coast, panha ndle, and some central areas intercept tools such as permeable surfaces or swales could be focused on because the soils will be able to percolate large quantities of water quickly. R esearch on low intensity grassed swales in s outhwest Florida has shown th at compared to a conventional style curb and gutter system, end of the pipe loads were 93% lower in total Nitrogen, 82% lower in total Phosphorous, and 95% lower in total suspended solids (Willis et al. 2012). Inland areas, such as central Florida around L ake Okeechobee, heavily organic soils provide high storage capacity and nutrient rem oval capabilities that are ideal for bi o retention and other storage tools. In areas where the soils are too sandy and water may percolate too fast or there is insufficient space above the water table for proper treatment, non structural practices such as low impact landscaping or above ground storage such as cisterns could be the focus. When asked to compare LID versus convention stormwater management designs, a large porti on (41%) of the professionals indicated that they believed LID to be more expensive than conventional methods This group tended to be those that have limited practice in designing and implementing LID projects. The 27% that thought LID cost less or much l ess, these respondents tended to be the ones with more experience in using LID. We believe that given a more robust sample, statistical analysis would help
37 to support this finding. Therefore, it is our suggestion that design/development firms who are conce rned or uncertain about LID costs and want to use these practices, should highly consider invest ing time and resources into gaining specialized knowledge and experience to fully understand the possible capital cost savings available The respondents who w ere in the variable category (27%) thought that LID co sts were mostly dependent on permitting process unknowns, location/site conditions, and LID tools considered in the design. This is not surprising as from the early discussions with respondents and a r eview of the literature indicated that LID costs are often dependent on site specific characteristics (Sample et al. 2003) The multitude of products and design strategies associated with LID allow for cost effective alternatives to be developed during the design process. Typically earthwork is the biggest expense on a land development project and the quantities are reevaluated throughout the design to manage the overall cost. S avings associated with LID are usually the result of reduced centralized stormwa ter infrastructure which allows for less earthwork ( excavation and grading ) less clearing and grubbing, and less hard piping/conveyance structures ( Kloss and Calarusee 2006 USEPA 2007). In order to realize these savings, individual LID practices must be viewed as part of the overall stormwater system. For example p ermeable surfaces usually cost $2 8 more than conventional surfacing per square foot. But w hen combined with good underlying soils (>0.5 in/hr. infiltration capacity) or aggregate storage space and given proper credits they can decrease stormwater conveyance and retention cos ts by as much as 30% (LIDC 2002 Clark and Acomb 2008 ). Overall, permeable paver stormwater management system cost s approximately $4.50 10 per sq ft. whereas conventional
38 concrete systems cost $9.50 11.50 per sq ft. (to manage the same quantity of water) (CRI 2005) The Florida Aqu arium case study is an excellent example of how pervious surfaces add costs to the project when they are viewed simply as an alternate surfacing option and not incorporated into the stormwater storage needs. Additionally, in Florida, high water tables sometimes force expansive shallow dry retention areas to be incorporated into the site design that have little functional value. Pervious surfacing stormwater management systems can be incorpora ted into parking lots to help allow expansive, shallow storage into a functional space. Another popular LID tool used in the case studies was bioretention areas which have estimated cost s of $3 15 per square foot (USEPA 2000). Bioretention areas are often combined with swale conveyance which range s from $5 (good soil) to $18 (poor soil) per linear foot. It is well documented that swale conveyance is two to three times less costly than hard piping / structural co nveyance which cost s $24 50 per running foot (USEPA 2000, CWP 1998). When comparing the LID options of a structural pervious paving system to a swale conveyance/bioretention syst em it can be seen how the costs are comparable and site conditions will truly dictate which LID scheme s are most functional and cost effective A review of the collected case studies offers some reference for local site conditions which may make it easy to reduce manufactured or centralized retention pond space therefore reducing c osts. Development sites with natural storage (wetlands, low land areas) capabilities, such as the Central Florida Residential and North Central Florida projects present an opportunity for large excavation cost savings when used for storage at the end of a LID t reatment train. In these situations, the wetlands offer an area to store water that has already been treated by other LID practices such as swales
39 and bioretention areas Excavation costs range from $6 20 per cubic yard to dig large retention ponds an d these foregone costs helped keep capital costs down In the Central Florida Commercial case study, swales designed with the multi ple purposes of infiltration, retention and conveyance allowed for the elimination of all on site dry retention ponds. This s mart use of required buffer areas not only saved a great deal in excavation costs and piping costs but it also increased the buildable space enough to gain an additional lot or two T he collected economic data from projects in our study presented ways to look at the cost effectiveness of using LID in retrofit or redevelopment projects. Nationally, many water rich states like Florida have dense, urban areas with old roadways and parking lots, from which stormwater runoff is discharged dir ectly into receivin g waterways. The Braden ton Roadway case study is a example of how redevelopment projects, of aging infrastructure, will often trigger regulations requiring the control and treatment of runoff due to updated stormwater rules. In ultra urban environments lik e the Bradenton Roadway, there is little or no space for the addition of centralized storage ponds or the input requires large utility reworking (Tim Foushee, personal communication, January 3, 2012). The Bradenton Roadway project incorporated decentralize d, LID tools into median s and underneath the bike lane to eliminate the need for pond space and was found to be the low cost estimate. There is no denying that c hanging development rules and procedures to accept innovative practices is a lengthy process wh ich takes a numerous resources and much collaboration (Gordon 2011). Some regulations h ave been altered to allow LID practices and economic benefits were realized (CWP 1998 Kloss and Calarusee 2006 MMSD
40 2010 ) In the long run LID could be incentivized an d incorporated into future development plans for controlling our biggest stormwater issues. Nationally, zero effect drainage discharge ordinances and stormwater tax credits h ave been incorporated and proposed to increase the voluntary usage of LID practice s (Romero and Hostetler 2007) These incentives often detail specific LID practices which will be granted acceptance in the cities/municipalities which helps clarify the process. This being said, they have had little effect to date because of lack of famil iarity with LID on the part of practitioners and that simply allowing LID to be permitted may not be enough of an incentive for the practice to spread A point repeated in the literature is that most development companies and municipalities which have real ized cost savings from using green infrastructure practices did so to achieve an environmental goal or because of an environmental ethos, not because of an initial cost analysis ( Civic Federation 2007 Macmullen and Reich 2007 ). A similar sentiment was gat hered from the early interviews and survey questions/responses from our research. When the sample was asked about their reasons for using/considering LID, water quality protection, reduced runoff volume, and were the three primary ones (Appendix B, Q7) Combining this with our findings that more experienced firms tended to think that LID costs les s, shows that firms must take a comprehensive approach to using LID to realize its full benefits. Also, because o f its on site management focus, LID could be a cost effective method which assists in achieving state and federal regulations, such as the proposed statewide Stormwater Rule and numerous Total Maximum Daily Load (TMDL) designations (Merriam 2011). Municipa lities which have undertake n a forward
41 thinking approach to using LID and related green infrastructure have often see n better environmental results but also ancillary savings due to suspension/exemption from TMDL litigation requirements or foregone enviro nmental restoration costs (Perry 2012) G iven the findings of this research Florida policy makers and stormwater regulators need to focus attention and funds on researching and promoting the most applicable LID tools for the regional conditions of the sta te A smoother and more clearly defined permitting process associated with using LID tools wi ll help attenuate concerns about d elays and project approvals and increase up front consideration for LID Although this will not completely dismiss perceptions of higher costs, it will help clarify the true capital costs associated with the alternative approach to stormwater management Our research indicates that LID has the opportunity to reduce capital costs for the private development industry. Combined with re search showing the ability of LID to control stormwater pollution issues prevalent in the state, better than conventional practices, makes an argument to begin incorporating and transition ing towards decentralized, green infrastructure approaches ( Harper a nd Baker 2007, Hood et al. 2007, Prince George's County 2000, Rushton 2001, Willis et al. 2012) This being said, o ur water resources in the state of Florida are arguably th e most important in an economic sens e due to their draw for tourism and recreation ability to supply drinking water to a large population, and support of many livelihoods. There must be greater attention focused on a multi faceted approach to land development that not only considers economic profits, but also stewardship and protection of our waters LID is a method of managing and treating stormwater which provides an answer to these goals better than our current ways
42 Figure 2 1. Percent of total responses from design professionals concerning perceptions o n the primary barriers to using low impact development in Florida. (n=22)
43 Figure 2 2 development compared to conventional stormwater management in Florida projects. (n=22)
44 Table 2 1. Surveyed Florida design categorized responses on why low impact development costs more, less or is variable compared to conventional stormwater management. Response Categories % of Total Response s in each Category Much More (n=0) No responses More (n=9) Construction costs 37.50% Design costs 31.25% Maintenance costs 18.75% Loss of development density 12.50% Equal/Could Not Determine (Variable) (n=6) Dependent on the specification/ location of development project 21.43% Dependent on regulation/permitting process unknowns 21.43% Dependent on LID tools used/considered 21.43% Information costs 14.29% Dependent on degree of up front planning for LID implementation 7.14% Dependent on underlying land value 7.14% Dependent on client's willingness to consider/accept the tradeoffs in project design 7.14% Less (n=5) Construction Costs 57.14% Increased buildable space due to decreased SWMF 28.57% Lack of understanding by prac titioners 14.29% Much Less (n=2) Construction Costs 40.00% Increased buildable space due to decreased SWMF 40.00% Increased market value 20.00%
45 Table 2 2. Summary of total cost savings associated with a low impact development approach compared to a conventional approach for five Florida case studies. Project Total LID c ost savings Central Florida Residential a $2,020,000 Central Florida Corporate Center b $1,200,000 North Central Florida c $2,925,000 Bradenton Road Project (2010) d $1,051,264 Flor ida Aquarium Base SWM e $249,000 Florida Aquarium Base SWM + Enhancements $294,000 f a, b ,c General project names at request of engineer d Adjusted back to 2008 dollars for the comparison e Compared to the original budget for the conventional design f Nega tive number indicates a higher cost for the LID scheme
46 Table 2 3 A summary of low impact development practices employed in the 5 Florida case studies. LID Tools Used in the Design Central FL Res. Central FL Corp. North Central FL Bradenton Road Project Florida Aquarium Permeable Surfaces x x x x x Vegetated Swales x x x x x Bioretention Areas x x x x x Minimized Grading and Filling x x x Cluster Building x Green Roofs x Stem Walls x x Narrow Road Design x x x Minimized Soil Compaction and/or Topsoil Stripping x x x Soil Amendments x Low impact landscaping water/fertilizer/energy x x x x Stormwater Wetlands x x Rain Barrels/Cisterns x Underdrains x Clarification Pond x
47 APPENDIX A CALL SCRIPT Good (Morning) Afternoon Mr/Mrs. (Name) My name is Daniel C. Penniman and I am a Masters student at the University of Florida. I am conducting thesis research on costs of low impact development (LID). Do you have about 5 minutes or should I call back at a different time? Through a snowball survey I was referred to your firm and specifically you by (ref e rs name). Particularly, I am collecting data to develop a Florida specific cost comparison between LID and conventiona l means of stormwater treatment. Are you familiar with LID? Low Impact Development (or LID) is a fairly new design technique which strives to replicate the pr e development hydrologic scheme of a development site. The focus of LID is to use a variety of tools to help better control flood events and remove impurities picked up by stormwater in a more natural manner than conventional pipe and pond management. For my research, a project (new or retrofit) which uses any two or more of the following tools will be considered an LID project. Permeable Surfaces Disconnected Downspouts Bioswales (Vegetated Swales) Decreased Soil Compaction and Minimal Stripping of Tops oil Bioretention Areas (Rain Gardens) Tree Box Filters Subsurface Retention Facilities Narrow Road Design Decreased Grading or Filling Soil Amendments and/or Aeration Cluster Building Green Roofs Low impact landscaping (e.g., plants that requi re less water) Stem Walls Rain Barrels/Cisterns or other storage practices A. I am calling to inquire about: 1. Has your firm considered utilizing two or more LID tools within any of your projects in the last 3 years? 2. If you have, was a cost c omparison between conventional and LID stormwater techniques performed for any of the projects ( this analysis can include any of the development phases )? 3. Are the results from that analysis available for any projects ( even if the project was not built at all or with the use of LID )?
48 If you were able to answer yes to one or more of these questions it would be a great benefit to my research if you or another professional from your firm, informed on these LID projects, could complete a specialized survey (possible responses) I do not know anything about LID/ Have never considered LID in a project design ask for contact information of another professional from their firm who may be able to help with thi s Our firm considered LID in a design o Ask if LID cost evaluation is available. If yes confirm that this information is important for you If no thank the person for their time, and the call Yes, our firm has considered LID and conducted cost analysi s keep going 1. The questionnaire is in electronic format (but we can send you a hard copy if you prefer) 2. pe rceptions anbout LID, and it should take about 5 10 minutes. 3. The second portion of the questionnaire is designed to get some hard cost data on projects where a cost comparison between LID and conventional stormwater management was performed. I am askin g for data on up to 4 projects. I understand that as a professional your time is extremely precious and limited. This data is fully intended to better inform the Florida design/construction community on LID costs and could be beneficial to progressive firms like your own. As a disclaimer, I would like to assure you that I will make the draft and final results available for your review. I will also maintain confidentiality if you do not wish the names, locations, or other information to be disclosed in my study (There will be a place on the questionnaire where you can choose to keep each projects specifics confidential). Would you be willing to participate in my research? If YES within the next couple weeks, I will send the data collection tools in an email, there will ask what email is) If NO ask if another person in their firm would be able to help. If yes record the name and phone number. Do you have any questions for me?
49 APPENDIX B SURVEY Dear Survey Participant, Thank you for taking part in this important study about low impact development (LID). This survey is designed to get a better understanding of the opinions and experiences that Florid a design, engineering, and development firms have had with LID use. The study is intended to better inform the Florida design/construction community. The survey includes (13) questions about your firm's past experience with, and opinions on various aspect s of LID stormwater management. For my research, if 2 or more of the tools in the list below were included in the project analysis, it is considered an "LID" project. If you are interested, the draft and final study results will be shared with you for rev iew. I will also maintain confidentiality of your responses. As a professional, I understand your time is extremely precious so I extend the greatest amount of gratification to you for helping me make my research the best it can be in generating important information for the Florida design/construction community and development regulatory agencies. Your participation in this survey is completely voluntary and you do not have to answer any questions you do not feel comfortable with. List of LID tools consi dered in the study: nd/or Aeration impact landscaping (e.g., plants that require less water) Q1. What is the name of your firm? Q2. How many years has your firm been in operation? Opened this year 1 5 years 6 10 years
50 11+ years Q3. To which Water Management District (WMD) does your firm (or office) submit the majority of stormwater permit applications for Florida proje cts? Northwest Suwannee St. Johns Southwest South Not possible to answer (Please explain why) Q4. For the past 5 years, please estimate the percentage of your firm's total design projects which have included LID tools (at any stage from plan ning to construction). < 1% 1 5% 6 10% > 10% (please estimate % in the space below) Not possible to answer (Please explain why) Q5. Select the 5 LID tools most frequently used by your firm in Florida projects. Permeable Surfaces Bioswales (Vegetated Swales) Bioretention Areas (Rain Gardens) Subsurface Retention Facilities Minimized Grading and Filling Cluster Building Green Roofs Stem Walls Tree Box Filters Narrow Road Design Minimized Soil Compaction and/or Topsoil Stripp ing Soil Amendments and/or Aeration Low impact landscaping (e.g., plants that require less water) Rain Barrels/Cisterns or Other Storage Practices
51 Others (Please Specify): Q6. For your firm, what have been the primary barriers to utilizing LID i n projects? Please select up to 3 choices below. Approval issues (calculation of water quality/reduction credits, slowed permitting process, etc.) Flood control performance issues/uncertainties Higher costs compared to conventional methods Lack of comprehensive resources/ training of contractors to implement LID LID operation and/or maintenance issues Construction site limitations Lack of field data for LID tools (nutrient removal efficiency, flood control, etc) Client disapproval Other (p lease specify): Q7. For the projects in which your firm incorporated LID tools (at least into the design phase), what were the primary reasons to use LID? Please select up to 3 choices below. Reduce runoff volume or flooding Local or downstream wate r quality protection Lower costs compared to conventional methods My firm's environmental or sustainability ethics LEED certification credits Increased lot/functional space yield Expedited project approvals Increased property value due to impro ved aesthetics/amenities Client request Current/possible requirements for TMDL designations or other environmental regulations Other (please specify): Q8. In your professional opinion, for the overall development process using LID for stormwater management in Florida is __________________ expensive compared to conventional stormwater management techniques. Much More More Equally Less Much Less Cannot Answer (please explain)
52 Q9. Based on your answer for Q8, why is LID more or less expensive than conventional stormwater management tech niques (Ex. construction costs reduced stormwater infrastructure, etc)? Please give explanation. Q10. What type regulatory or incentive policy can increase the rate of LID implementation the most? Q11. Please estimate the # of employees in your firm/company (all offices). Q12. Is there specific information that you/your firm would like to learn about in order to be more effective at implementing LID? Q13. Please include the names o f any other Florida design firms or professionals, that you know have incorporated LID tools in a project design. This information will be used to make the study more comprehensive.
53 APPENDIX C COST QUESTIONNAIRE
54 This questionnaire focuses on individu al projects for which your firm calculated a documented LID (vs conventional) cost comparison. There are multiple tabs of formatted worksheets at the bottom, please provide data on up to 4 different projects. Please include available cost data for projects of any following designation. 1.) built/being built using LID tools and a cost comparison was developed; 2.) built/being built not using LID tools but LID was considered in planning and a cost comparison was developed; 3.) still in planning but LID is be ing considered and a cost comparison has been developed; 4.) not built at all but LID was considered and a cost comparison was developed; Notes: If it is more convenient or saves time to return cost data in a different/raw format through mai l/email that is encouraged. My mailing information is included in the sent email. For my research, a project which uses 2 or more LID tools is an "LID Project." If any data is not available, leave cell blank I will follow up to your response with a very short call to clarify any data and/or to answer any follow up questions There are comment areas in all of the sections in case any data needs to be clarified I understand that finding the data may take some time but the comprehensive results will be pow erful in helping understand the barriers to, and provide additional knowledge for LID usage in the state of Florida. Your response is critical to my research due to the relatively small sample size available for this study Please note any information whic h needs to remain confidential in comments. I hope the product will be useful to progressive firms such as yours. Thank You! 1. Project Specifications Answer in this column Comments: Project designation (1/2/3/4, see introduction above) Name of pro ject Location of project (county, city) Does the name and location of this project need to remain confidential? (yes or no: please specify in comments any other data that needs to be kept confidential)
55 Type of project (Residential/Commercia l/Office/Industrial) Size of project (in acres or square feet) Major soil type(s) of project (A/B/C/D) Average depth of water table in developable areas of site 3. LID Tools Incorporated Into the Project Design Place an X in this column if used in Design Comments: Permeable Surfaces Bioswales (Vegetated Swales) Bioretention Areas (Rain Gardens) Subsurface Retention Facilities Minimized Grading and Filling Cluster Building Green Roofs Stem Walls Tree Box Filters Narrow Road Design Minimized Soil Compaction and/or Topsoil Stripping Soil Amendments and/or Aeration Low impact landscaping (e.g., plants that require less water) Rain Barrels/Cisterns or Othe r Storage Practices Others (Please Specify):
56 4. Conventional vs. LID Cost Comparison Please Note: There is a space for comments in case any data figures need to explained or clarified. See bottom section for areas to enter data fo r unique economic benefits of LID not comparable to conventional management. Conventional Development Cost LID Cost Comments: Please briefly explain how you calculated these numbers. Include descriptions like: Just materials, materials+construction, just construction, etc. Lot/Building size yield (This will not be a cost figure, please include # of units, sq. ft., etc) Planning and Permitting Site grading and preparation Stormwater infrastructure (pipes, ponds, curbs, versus swales a nd bioretention, etc.) Paving/surfacing (roadways, driveways, and sidewalks. Please include type of surfacing for LID in comments) Landscaping Stormwater fees for municiple stormwater control Maintenance ( Please specify for what period of time ex. $/month, or $/year) Other (please specify): Total Project Costs 5. Notable Economic Benefits of LID Note: LID may have some additional benefits that are not comparable to conventional. If possible, please give an estimated dollar amount Dollar Amount Comments: Please give a brief description and/or any information you feel is important. If there is not an associated dollar amount please try to qualify. Permit breaks Grants Incentives (t ax break, expedited approval, etc.)
57 Other (Please Specify) Total END (move to next tab for additional projects)
58 LIST OF REFERENCES Acomb, G., 2009. LID vs. Conventional Design: The Madera Case Study. The National Association of Home Builders 75, 22 27. Bowman, T., Thompson, J., 2009. Barriers to Implementation of Low Impact and Conservation Subdivision Design: Developer Perceptions and Resident Demand. Landscape and Urban Planning 92 (2), 96 105 Castillo, J. J., 2009. Snow ball Sampling. Accessed online from Experiment Resources at http://www.experiment resources.com/snowball sampling.html Center for Watershed Protection (CWP), 1998. Better Site De sign: A Handbook for Changing Development Rules in Your Community. Ellicott City, MD Civic Federation, 2007. Managing Urban Stormwater with Green Infrastructure: Case Studies of Five U.S. Local Governments. http://www.cnt.org/repository/ GreenInfrastructureReportCivicFederation%2010 07.pdf Clark, M., Acomb, J., 2008. The Florida Field Guide to Low Impact Development: Stormwater Management Practices for A pplication in Master Planned Community Development. Program for Resource Efficient Communities, University of Florida Coffman, L., 2000. Low Impact Development Design: A New Paradigm for Stormwater Management Mimicking and Restoring the Natural Hydrolog ic Regime, an Alternative Stormwater Management Technology. Conference Proceedings from the National Conference on Tools for Urban Water Resource Management and Protection. Conservation Research Institute (CRI), 2005. Changing Cost Perceptions: Analysis of Conservation Development. http://www.chicagowilderness.org/files/ 1613/3087/0421/Cost_Analysis_Exec_Summary.pdf Dietz, M. E., 2007. Low Impact Deve lopment Practices: A Review of Current Research and Recommendations for Future Directions. Water Air Soil Pollution (186) 351 363. Florida Department of Environmental Protection (FDEP), 2008. Integrated Water Quality Assessment for Florida: 2008 305(b) Re port and 303(d) List Update. Division of Environmental Assessment and Restoration, Bureau of Watershed Management. http://www.dep.state.fl.us/water/docs/2008 Integrated_Report. pdf Godwin, D. et al., 2008. Barriers and Opportunities for Low Impact Development: Case Studies from three Oregon Communities. Oregon Sea Grant and Oregon Sta te University ( ORESU W 06002 ). Gordon, E. 2010. Implementing LID for New Development.
59 Harpe r, H. H., Baker D.M., 2007. Evaluation of Current Stormwater Criteria within the State of Florida. Final Report. Environmental Research and Design, Inc. Prepared for FDEP (Contract No. S0108). Heaney, J. P., 2012. Class Lectures: Stormwater Overview. Wate r Resource Planning and Management. University of Florida Environmental Engineering Department, Gainesville, FL. 01 March 2012. Heaney, J. P., Lee, J. G., 2006. Methods for Optimizing Urban Wet Weather Control S ystem. USEPA, Washington, DC (EPA 600/R 06 /034 ) Heaney, J.P., Sansalone J., 2012. A Vision for Urba n Stormwater Management in 2050. Chapter 17 in Grayman, W. et al., Ed., Toward a Sustainable Water Future Visions for 2050. ASCE Press, Reston, VA. Hood, M. J., et al., 2007. Comparison of Stormwa ter Lag Times for Low Impact and Traditional Residential Developm ent. Water Resource Association 43 (4), 1036 1046. Hubbart, J. A., 2011. Low Impact Development: New Tricks for Older Communities in the Central US. International Erosion Control Association Kipp, J.M. et al., 2011. Implementing Low Perspectives. Florida Watershed Journal 4 ( 1 ), 12 18. Kloss, C., Calarusee, C., 2006. Rooftops to Rivers: Green Strategies for Controlling Stormwater and Combined Sewer Overflows. N atural Resource Defense Council, New York. http://www.nrdc.org/water/pollution/rooftops/contents.asp Lehner, P.H. et al., 2001. Stormwat er Strategies: Community Responses to Runoff Pollution. Natural Resources Defense Council http://www.nrdc.org/water/pollution/storm/stoinx.asp Litpan, T., Brown, C.K., 1996. A cost comparison of Conventional and Water Quality Based Stormwater Design. City of Portland. Bureau of Environmental Services. Portland, OR. Livingston, E. H., McCarron, E., n.d. Stormwater Management: A Guide for Floridians. Florida Department of Environmental Regulation. http://www.dep.state.fl.us/water/nonpoint/docs/nonpoint/Stormwater_Guide.pdf Low Impact Development Center (LIDC), 2002. Permeable Paver Costs. http://www.lid stormwater.net
60 MacMullen, E., Reich, S., 2007. The Economics of Low Impact Development: A Literature Review. ECONorthwest. Eugene, OR Macmullen, E., Reich, S., 2009. Low Impact Development at the Local Level: develope Creek Sustainability Initiative ECONorthwest. Eugene, OR Merriam, J., 2011. Low Impact Development Comes to Flo rida. Florida Watershed Journal 4 (1) 1 6 Milwaukee Metropolitan Sewage District (MMSD), 2010. Fresh Coast Green Solutions: http://v3.mmsd.com/AssetsClient/ Documents/sustainability/SustainBookletweb12 09.pdf Montalto, F., et al., 2007. Rapid Assessment of the Cost Effectiveness of Low Impact Development for CSO Control. Landscape and Urban Planning. 82 (3) 1 15 Perry, J.S., 2012. Sarasota County Nutrien t Management. Conference Presentation at the University of Florida Water Institute Symposium. Reitz Union, Gainesville, FL. 16 February 2012 Powell, L.M. et al., 2005. Low Impact Development Strategies and Tools for Local Governments: Building a Business Case. LMI Government Consulting. Report No. LID50T1. Prince George's County, 1999. Low impact development an integrated design approach EPA 841 B 00 003. Department of Environmental Resources Programs and Pl anning Division, Maryland. Romero, M., Hoste tler, M. E., 2007. Policies That Address Sustainable Site Development. Institute of Food and Agriculture Sciences, University of Florida CIR1520/UW254 http://edis.ifas.ufl.edu/uw254 Rushton, B.T., 2001. Low Impact Parking Lot Design Reduces Runoff and Pollutant Loads. Journal of Water Resources Planning and Management 127 (3) 172 179. Rushton, B.T., n.d. BMP Monitoring: Methods and Evaluations. Southwest Florida Water Management District. Ryan, R., 2006. Comparing the Attitudes of Local Residents, Planners, and Developers about Preserving Rural Character in New England. Landscape and Urban Planning 75 (1 2), 5 22.
61 Sample, D. J., et. al., 2003. Costs of Best Management Practices and Associated Land for Ur ban Stormwater Control. Journal of Water Resources and Planning Management. 129 (1) 59 68 United States Environmental Protection Agency (USEPA), 2000. Low impact develo pment (LID), a literature review USEPA Office of Water, Washington,DC (EPA 841 B 00 005). USEPA, 2003. Protecting Water Quality from Urban Runoff. Washington, DC. Report No. 841 F 03 003. http://www.epa.gov/npdes/pubs/nps_urban facts_final.pdf USEPA. 2005. Low Im pact Development Pays Off. Nonpoint Source News Notes. 75 7 10. http://www.epa.gov/NewsNotes/issue75/75issue.pdf USEPA. 2007. Reducing Stormwater Costs through Low Impact Development (L ID) Strategies and Practices Washington DC (EPA 841 F 07 006). United States Department of Transportation (USDOT) 1996. Retention, Detention, and Overland Flow for Pollutant Removal from Highway Stormwater Runoff, volume I: Research Report. U.S. Depar tment of Transportation, Federal Highway Administration. Williams, S., Wise, W.R., 2009. Economic Impacts of Alternative Approaches to Storm Water Management and Land Development. Journal of Water Resource P lanning and Management 135 (6), 537 546. Willis A., B. et al., 2012. Grassed swale drainage provides significant reductions in stormwater pollutant loads. Florida Scientist, November (in review). Zwick, P. D., Carr, M. H., 2006. Florida 2060: A Population Distribution Sce nario for the State of Florid a. University of Florida
62 BIOGRAPHICAL SKETCH Daniel Penniman earned his undergraduate degree from the University of Florida in international food and r esource e conomics. While attending UF in und ergrad from 2004 2008 he was a member of the varsity swimming and diving team earning 14 all A merican and 14 all SEC titles. Some of his future research interests include optimization and promotion of decentralized stormwater management and re use practices in highly urbanized and developing coastal areas