ROADMAPS
January 21, 2021
Pervious Maintenance in the Pacific
Northwest
• Photos and examples of pervious installations
• NAVSEA sweeping comparisons
• Pervious Maintenance Guide
• UNHSC study
ROADMAPS
January 21, 2021
Rego Park, Queens, NY:
test installation in one
branch of storm water
sewer system reduced
outflow to Long Island
Sound by 60%
Lack of sweeping
maintenance created
clogged permeable in
only 18 months.
• Video: https://youtu.be/‐eQLx9S9K2I
ROADMAPS
January 21, 2021
Rego Park, Queens, NY
Extend functionality of
pervious by cleaning
with deep clean after
the two heaviest bio-
loads of the year:
spring and fall. It is
best to manage the
pavement than to
occasionally recover
the pervious.
Same strategy across
country: Pervious
pavement lanes at
each side take the
flow from entire
roadway
Poulsbo, WA
Water running down
street in background
tracked down hill in
road irregularities.
Difference in these
two photos was one
pass of high-pressure
spray wash of
pervious lane. Water
flow ceased while
rainstorm continued
ROADMAPS
January 21, 2021
Poulsbo, WA
Salem, OR
Pacific Northwest
issue: Moss grows in
new soil trapped in
pervious causing slip
hazards and
exacerbating lack of
percolation
In Salem, the
unmanicured
landscaping uphill to
the right continually
floods the pervious
sidewalk with soil
How can you tell if
pervious is
percolating properly?
ASTM 1701 . . . or
Kuert Concrete,
South Bend, IN
Run a hose on the
pervious surface. . . or
Olympia, WA
Visually inspect just after a
rain event . . . . . or
Olympia, WA
Use the most economical tool ever to
inspect your pervious. . . . . An umbrella
Pervious works because of
the voids. It plugs in the top
3/8 inch. After it plugs, the
surface topography
disappears, covered with
adhered solids.
Pavers are the same, except
the plugging occurs in the
water path between the
pavers themselves.
Cleaning between the
pavers also removes the
aggregate that must be
replaced or restored
METALS RESULTS
• See slide two for MCRRS sample locations. Value presented here is the difference between the collected water and feed water.
• Collection rates are calculated values based on area cleaned, water volumes collected and MCRRS vehicle speed.
Area CB‐121
Area CB‐121 Bridge Caisson Maintenance Work
40‐79% Total Solids Reduction
94‐95% Suspended Solids Reduction
89‐90% Zinc Reduction
50‐77% Copper Reduction
TSS
Aluminum
Barium
Copper
Iron
Lead
Titanium
Zinc
Dust Broom Levels (mg/L)
102.0
245.0
0.7
0.01
0.02
2.8
0.01
0.04
2.0
Wet Vacuum Levels (mg/L)
864.7
1,494.0
14.1
0.20
0.56
116.3
0.21
0.97
69.8
Dust Broom Levels (mg/L)
6.3
51.0
0.1
0.01
0.2
0.01
0.1
Wet Vacuum Levels (mg/L)
89.0
905.0
1.4
0.04
0.13
50.3
0.03
0.08
7.8
Collected – Feed (mg/L)
13,184.3
14,940.0
105.2
1.1
3.0
267.9
1.1
5.9
216.7
Dust Broom (lbs/acre)
0.04
0.0004
0.0009
0.21
0.001
0.003
0.16
Wet Vacuum (lbs/acre)
0.88
0.01
0.03
4.59
0.01
0.06
4.31
MCRRS (lbs/acre)
431
489
3.44
0.04
0.10
8.76
0.04
0.19
7.09
Solids Collection Rates
Average Sample Results
Before
After
MCRRS
Note: Metals exist primarily as particulates (~>95%)
Test Case 2
NAVSEA Research
6PPD
Surface pollutants adhere
to the pavement. Adhered
solids and pollutants can
only be released with
application of high energy
High pressure spray
outperforms mechanical
sweeping: 30:1 for solids;
44:1 for zinc.
Needs to be
studied
High pressure spray cleans
any hard surface and
subsurface in pervious. The
stream ricochets into the
voids, transferring energy to
the foreign solids that move
to the point of least
resistance: up and out
Triverus technology
contains that high pressure
spray in an enclosure
where the solids and water
slurry that is formed can be
lifted and contained from a
5-ft wide path
Lifting and containing bird
poop from a port
environment
High pressure wash has to
remove adhered surface
solids before reaching
solids clogging the voids in
the pervious. Note surface
topography before and after
pressure spray application
Hybelos Park, Federal Way
AMTRAK, Seattle
High pressure wash has to
remove adhered surface
solids before reaching
solids clogging the voids in
the pervious. Note surface
topography before and after
pressure spray application
Process is the same for
both asphalt and concrete
COMMONNAME
FACILITYDE
SQ FT
Notes
Failed infiltration Test
Asotin
Asphalt
8984
looked good in 2019
East lane in front of 4713, 4 LF North of driveway wing, 5.5 LF off face of curb
Asotin
Asphalt
11631
looked good in 2019
Center of road 25LF south of ADA ramps at 47th
West lane center of private walk to 4620, 5 LF from face of curb
East lane in center of lane in front of 4609 2LF North of driveway wing
Asotin
Asphalt
10940
looked good in 2019
At property line between 4517/4513 in center of road
West lane 33LF South of ADA ramps of 45th, 3 LF off face of curb
Pervious inspection results.
Clogged pervious can still
look clean. Main issue is
subsurface, topography is
one of two primary clues
Looks good but fails tests
COMMONNAME
FACILITYDE
SQ FT
Notes
Failed infiltration Test
Alaska
Concrete
2880
some areas heavy soil
East side in front of 6215 12LF North of the top of driveway wing in center of parking strip
Alaska
Concrete
4950
some areas heavy soil
East side in front of 5845 1 LF North of the top of driveway wing in center of parking strip
Alaska
Concrete
5600
some areas heavy soil
West side in front of 6016, 1 foot South of driveway in center of parking strip
West side in front of 6042, 2 LF South of the driveway in the center of parking strip
West side in front of 6060 5 LF South of the driveway in the center of the parking strip
Pervious inspection results. Temporary scars
ARE visible from construction activities,
resident abuse. Without routine deep cleaning,
clogging will extend beyond the scarred areas.
• Video: https://youtu.be/PycTmWbl‐cU
ROADMAPS
January 21, 2021
Pervious Maintenance in the Pacific
Northwest
www.Triverus.com
Other Uses
Pick up Sweeper
Chassis
Brush Hog
Front broom
Dock areas
Parking Garages
Mildew Removal