20221183 Ver 2_Calculations for stream_20221111

717 Edmund St Raleigh, NC 27604 - Buffer Encroachment Proposal
Currently in Zone 1 + 2
Carport built in 1980 per tax records (Grandfathered pre-1997)
9.2 x 26.5 = 243.8 sqft
Of this amount, approximately 60% falls within Zone 2, or 146 sq.ft and nothing in Zone 1.
Detached Garage built in 1993 per tax records (Grandfathered pre-1997)
24.3 x 24.3 = 590.49 sqft
Of this amount, approximately 90% (531 sq.ft) falls within Zones 1 & 2. Of that, approximately 80% (425
sq.ft) is in Zone 2 and 20% in Zone 1 (106 sq.ft).
Single Family house built in 1950, including a deck & porch. In addition, there is a driveway extending
to the garage and under carport (all currently impervious area)
Proposed Plans
Both the carport & detached garage are being removed. In their place, we are proposing to build an
Additional Dwelling Unit (ADU), as well as replace the current home with a new home, some of which
will be built inside the buffer area. This construction may occur in phases where the ADU is constructed
before the new home is built. The overall impact of these plans to Zones 1 & 2 will be as follows:
• The sq.ft of the foundation footprint for the ADU & home within Zones 1 & 2 is approximately 1,200
sq.ft. Of that, 80% (960 sq.ft) will fall in Zone 2, and approximately 20% (240 sq.ft) within Zone 1.
A 6' perimeter fence will be installed around the property, with a portion inside Zone 1. No disturbance
to the vegetation will occur for the fence installation.
Net Calculations
Total removed:
Zone 1: 106 sq.ft
Zone 2: 571 sq.ft
Actual Net Increase after completion
Zone 1: 134 sq.ft
Zone 2: 229 sq.ft
Total proposed added/request for approval:
Zone 1: 240 sq.ft
Zone 2: 800 sq.ft
Total Amount of Reserved riparian credits:
Zone 1*(rounded up): 450 Credits (150sgft x 3:1 ratio)
Zone 2: No credits required
Few notes of consideration:
• Construction will attempt to be pushed to the front portion of each zone, i.e. none of the proposed
construction within the zones will occur close to the creek, but rather the front portion of each zone.
• Erosion control fabric will be placed along the property during construction to limit run off
• All roof runoff will be diverted through gutters and dispersed evenly via points as far forward as
possible, so all runoff is slow and natural by the time it reaches the rear of the lot.