“Pavement Audit” for Greenville and Pickens Counties Diagnosis Report to Focus Group January 25, 2006
Presentation Overview Lawrence Group Scope of Audit Audit Methodology Recommendations/Findings Questions/Feedback/Next Steps
The Lawrence Group Founded in St. Louis in 1983 Carolinas office in Davidson, NC Town Planning & Architecture Municipal, non- profit, and developer clients
Lawrence Group Projects
Mooresville, NC Code
Haynie-Sirrine Master Plan – Greenville, SC
General Development Guidelines – Research Triangle, NC
Active Living Assessment
Concord-Roberta Church Small Area Plan - Concord, NC
Woodlands- Davidson, NC
Belmont Reserve- Belmont, NC
Project Scope
Saluda-Reedy Watershed “...non-point source pollution – sediment, nutrients and waste carried by storm water – is now the chief threat to these rivers... It will take a concerted effort by community leaders across the Upstate to effectively address the threats of non-point source pollution fed by rapid development...” -SRWC
Project Scope “... audit of paving requirements in the codes and ordinances of Greenville and Pickens Counties...” “Identify opportunities...to reduce the amount of impervious cover generated by new development.”
Project Scope
Ordinances Reviewed Greenville County –City of Greenville – Greenville LUDO –Fountain Inn – Greer – Mauldin – Simpsonville – Travelers Rest Pickens County – Central – Clemson – Easley – Liberty – (Pickens)
Methodology Zoning Ordinances and Land Development Regulations Based on “Builders for the Bay” process ( 10 major categories; 36 factors
Methodology Major Categories –Street width –Right-of-way width –Cul-de-sac design –Street drainage (swales v. curb & gutter) –Parking ratios –Shared parking –Parking lot design –Parking lot landscaping –Sidewalks and planting strips –Driveways
Imperviousness Rooftops + Car space
Transport-related impervious cover: 60-70% (streets + parking areas) Roof tops: 30-40% Imperviousness
Street Design
Local Streets: feet Could be as narrow as ft Street Width
Minimum street widths Street Width
Local Streets: feet Cul-de-Sac streets: ft –Could be as narrow as 18 ft Manufactured home park streets: ft –Should be same as local streets Alleys: feet (Greenville County standard is good: ft)
Street Width Local Streets: ft Cul-de-Sac streets: ft Manufactured home park streets: ft Alleys: ft (Greenville County standard is perfect) Collector Streets: ft –Could be as narrow as 20 ft –Consider parking, bike lanes, turn lanes
Curb Radii ft (Greenville County) Pickens Co: Not specified AASHTO Guidelines: –Local/local: ft –Local/collector: ft –Collector/collector: ft
Right-of-Way Width ft; typically 50 ft Could be as narrow as ft. Allow utilities in the street
Cul-de-sac Design Typical: 40 ft (Greenville: 41 ft; Clemson: 35 ft) Landscaped Islands: 8 of 13 allow Alternate turn-arounds: – Greenville: yes – Pickens: no
Cul-de-sac Design Cul-de-sac islands: –Greenville Co.: typically yes –Pickens Co: typically no
Open Channels/Swales Only Clemson, Easely, Liberty require curb & gutter on all streets Pickens County swales: < 2 dua; slopes “not excessive” Tom Schueler: –No slopes > 5% –Runoff velocities > 4-5 ft/sec. –Soils/climate don’t allow dense turf –Water table < 1 ft below channel –No densities > 3 dua
Sidewalks Context-sensitive requirements –Based on street-type (Clemson) –Development density (> 2 dua) –Proximity to schools (1-1.5 miles) One side only generally Alternate networks: 4/13 codes
Sidewalks Street-type based (Clemson): Density-based (FHWA): Street-type# of unitsSidewalk Cul-de-sac25 SF/43 MFOne side Access25 SF/43 MFOne side Sub-collector62Both sides Collector125 +Both sides Commercial areas: Both sides > 4 dua:Both sides 1-4 dua:One side < 1 dua:None
Sidewalks Sidewalk width: typically 4 ft min ITE & FHWA: 5 ft min.
Planting Strips & Trees 5/13 codes require planting strip 2-3 ft wide –6-8 ft recommended for street trees No codes require street trees Benefits of trees –Reduce runoff volumes –Increase soil infiltration –Increase soil water storage –Reduce erosion –Shade prolongs life of asphalt; reduces runoff temperatures –Shade: cars, pedestrians, homes –Improve air quality –Aesthetics (= increased property values)
Planting Strips & Trees
Parking Areas
Parking Ratios Wide variation in requirements Not based on reliable research Shopping Centers –2-6 spaces/1000 sf in Greenville Co. –4-5 spaces/1000 sf in Pickens Co. –10 spaces/1000 sf for food stores in Central, Easley, Liberty –ICSC: 4/1000 yields surplus 99% of time Parking requirements waived in most CBD’s
Parking Ratios Recommendations to consider: Use draft Greenville LUDO model –Low minimums (2/1000 sf for retail) –Maximums (use current minimums) Allow on-street parking to count Waive/reduce parking req’mts in all CBD’s and other mixed- use nodes Reduced minimums for transit service
Shared Parking All codes allow except Clemson No incentives for sharing 50 or 100% of spaces may be shared “each parking space may be counted for each activity” (Central, Easley, Liberty) Greenville LUDO offers more complex/accurate formula
Parking Lot Design Stall width: ft 2 rows & aisle: ft –60 ft is adequate Compact spaces: 3/13 codes –Limited benefit Pervious Pavement (good!): –Wide variation: not allowed; allowed; required –Pickens Co.: allowed but not req’d –Greenville Co.: req’d for % over minimum
Parking Lot Design
Parking Lot Landscaping Greenville Co.: All but Fountain Inn Pickens Co.: Clemson, Easley Range of applicability: –1-60+ spaces; new and/or expanded –Clemson, Greenville Co. extremes Required planting: –Greenville Co.: ~ 1 tree/10-20 spaces –Pickens Co.: 5-10% of area No required curbing: Good! No biorention encouraged/required
Parking Lot Landscaping Bio-rentention
Parking Lot Landscaping Bio-rentention: Wilmington, NC
Driveways Clemson & Mauldin allow permeable driveways (all other codes silent) Residential Setbacks: ft; generally 20+ –Reduce front setbacks to 20 ft or less
Other Issues Minimum lot size –Consider minimum density instead –Provide incentives for clustering Encourage Alleys in higher density SF (8+ dua) LEED-ND (Leadership in Energy and Environmental Design) Land use policies –Greater density = less impact Transportation Demand Management
Next Steps Questions/Discussion