Design Considerations for Marina Boat Wash Pads to meet NPDES regulations

1. By: Marty McDonald
HDB Marine
April 8, 2010

3. Vessel Generated Wash Wastewater
Marinas conducting vessel maintenance activities such as mechanical repairs,
refurbishing, painting, fueling and cleaning operations are required to have a
Basic Industrial Storm water General Permit (General Permit). The permit was
designed to protect the coastal environment from pollution by eliminating the
potential for storm water to come into contact with pollutants. Marinas
sanctioned by the General Permit are required to prepare a Storm water
Pollution Prevention Plan (SPPP). By May 31, 2009 marinas must eliminate the
discharge of vessel wash water into surface and ground water. Marinas have the
option of ceasing the practice of washing vessels or can capture the water and
recycle the wash water, haul the wash water for proper disposal or request
permission to connect to the sanitary sewer where applicable.
Wash Wastewater Characterization and Data
Wastewater generated from washing vessel bottoms can contain various levels
of both solid and dissolved metals (copper, zinc, lead, iron and other metals),
organic materials (barnacles, tube worms and algae) and salts. The amount of
lead in the wastewater can be greatly reduced by removing the sacrificial
anodes prior to pressure washing. Studies have indicated that the metals
commonly found in vessel wash wastewater bind preferentially to fine particles.
It should be noted that these fine particles and bound metals can be difficult to
remove from the wastewater through filtration. In addition, when the
wastewater is recycled and particles remain marina operators have reported
that it can lead to the early breakdown of the pressure washer. Marina
operators have alleviated this problem by passing the water through a 50
micron filter.
The I BOAT NJ is currently funding several wash wastewater studies at the
following marinas in New Jersey: All Seasons Marina, Dillon’s Creek Marina,
Viking Marina. Information on the type of systems they are testing is available
below and data on the wash wastewater will be posted as it becomes available.
Several states have conducted an analysis of the wash wastewater and there
information is available by clicking on the links below. Connecticut
Maine
New Jersey - coming soon
Washington

4. EPA - NPDES
o Federal Law established by EPA
o EPA does not lend assistance
o Is enforced by the State
o Extreme enforcement – fresh city water has
been considered as toxic
EPA - Suggested Solutions
o Closed Loop Recycling Systems – equipment
cost $10,000 to $30,000
o Treat and discharge to Public Sewage System
equipment cost $25,000 to $75,000
o Containment followed by offsite disposal
cost is $1.50 to $3.00 per gallon
o Cease washing boats

5. Marina Facilities with Boat Wash Operations
• Dry Storage Marinas – primarily rinsing the
boats off – removing salt water, trace films of
hydrocarbons and organics
• Boat Yards – paint chips, organic growth,
trace metals and hydrocarbons
• Seasonal Haul-out Operations – organic
growth, some paint, trace metals and
hydrocarbons
• Commercial Boat Wash Operations - organic
growth, some paint, trace metals and
hydrocarbons

6. Boat wash operations are primarily dealing
with organics and paint chips.
Some metals and hydrocarbons. Heavy
metals have been reduced with new bottom
paints.

7. Pressure Washers & Water Volume
• Average pressure washer is 4 GPM with 2000 to 3000 PSI
• Commercial sprayer with 5 GPM and 1500 PSI – delivers super results
• CMTA – extensive study 2008 – the average amount of water used to wash a
boat is = 1 gallon / linear foot of boat
• 30’ boat = 30 gallons, 50’ boat = 50 gallons
• Big Boat Haul-out facilities wash a maximum of 10 boats a day per wash area
(informal fact gathering)
• Majority of Boat Yards use water only – no cleaners – just pressure!
• Wash 10- 40’ boats in a day – use 400 gallons of water
• 15% to 20% of wash water is lost due to evaporation, seepage, film stays on the
boat, etc. Recycling Systems routinely replace the lost water with fresh water.

8. Collecting the Wash Water
Wash Pad Design Requirements
• Impervious materials – concrete, plastic,
rubber, asphalt
• Must capture and contain the wash water
• Must properly handle Rain/storm water
Wash Pad Options
• Permanent Wash Pads
• Portable or Temporary Use Wash Pads
• Retro Fitting Existing Permanent Pad Areas

9. Permanent Designs
Good Practice
• Use the wash pad as the first filter to settle out large particles –
sweep & clean daily
• Slope – 1/8 inch per foot
• Use engineer or qualified contractor to design the pad for loads,
soil conditions, tire wear & equipment safety operations
• Cost Varies – 22’ x 60’ pad cost $15,000 to $30,000
• Options include raised trough designs and center trough designs
• May use bag filters in troughs

10. Raised Trough Entry
• wash water enters
the 3 holes
• Holes are closed
when not washing so
that rain/storm
water is diverted to
the marina runoff
system
Small Sump Design
• 24” x 24” x 32” deep
• Entries & exits for the
electrical service, sump
pump discharge and
Recycle System Drain
• Simple to maintain &
clean, minimizes odor
problems

11. Center Trough Design
• Unlimited Equipment
movement
• Trough / Grate feeds
the water to a diversion
selection point where
wash water is sent to the
Recycle System and/or
rain water is diverted to
the storm runoff area
• Trough is cleaned at
close of each wash day

12. Center Trough Pad
• 6’ Fence- overspray
• Pad slope : 1/8”/FT
• Sump Pump feeds in-
ground settling tank
• Recycling Equipment
picks up water from in-
ground tank
• Designed for 400 +
boats

13. Recycling Equipment is located in heated
building for winter operations.

14. Above Ground Settling Tank
• 500 gallon settling cone Tank – settle out large particles
• Used with large washing operations (300 – 500 boats)
• Settling tank feed water to a transfer tank/pump that feeds
the Recycling System
• Recycling System is equipped with auto-circulation that
circulates all water/tanks through a UV light treatment and
bromine oxidation unit to mitigate organics and eliminate
odors

15. This pad is built on a
hard surface area.
Pad is designed for
very large forklift loads
for dry storage facility.
New pad to be built
in the area where the
boat is.
This is a fill area and
will require driven
piles to support the
load of a 50 ton
travel lift and large
forklift.

16. Unique Design
• 1000 gallon in-ground
settling tank
• 400 gallon above ground
settling tank w/bag filter
• feeds to a Settling Pond
on site

17. Filter Cloth – over pervious pad
• Temporary solution – Connecticut
• Will install a wash pad in 2010

18. Portable or Temporary Use Wash Pads
• Constructed with impervious materials
• Cost Varies: $5 to $15 per SF
• 22’ x 60’ = $6,600 to $19,800
• Many Manufacturers and suppliers – Hydro Engineering, Kyoto
• Proper preparation of area underneath the pad is critical
• Wash water may be pumped or vacuumed from collection area

20. Retrofitting Existing Concrete Pad
• Save Money! Take advantage of exiting pad
• Boatyards and marinas with Travel Lift equipment have a heavy duty
pad that is used as a wash area.
• Determine slope and water flow on the pad
• Use curbs or burms to guide the water
• Use manufactured trough & grate to intercept and collect the water
• Use manufactured collection boom to intercept and collect water
• Must allow for proper handling of rain and storm water
• Must capture and contain the wash water
Determine Pad Slope
• Survey levels
• Use water

21. Manufactured Trough Drains with Grate
• Manufacturers – Nationwide – Factory Installers
• Modules designed for specific load applications
• Can retrofit or install in new pad
• Modules designed to slope in desired direction

22. Manufactured Boom Collectors
• Designed in modules
• Many designs are equipped with vacuum pump
• May be used with temporary pads
• Modules designed to slope in desired direction

23. Retrofit Options for Existing Wash Pad
• Existing pad size: 32’ x 80’
• Slopes to the bulkhead pickup area
• Is serviced by a 30 ton Travel Lift and large forklift
• 18” thick concrete pad – 20 years old – structurally sound
• Has minor surface cracking that can be sealed
• Two options

24. Install Commercial Drain System & Collection
Sump
Existing Pad Size: 32’ x 80’
Retrofit Cost: $10,500 to $12,500

25. Install Curbing & Collection Sump
Existing Pad Size: 32’ x 80’
Retrofit Cost: $1,500 to $2,500

26. Existing pad slopes to the front
• Install gutter to drain water to sump - $2800
• Install factory drain with trough cover- $6000
• limited curbing required - $800
• Provide Flow-Through Forklift Stop- included

28. Wash Pad Collection Designs
• There are viable options for almost all
marina operations – permanent pads,
portable pads, retrofitting existing
• Marinas should establish “Best Management
Practices”
• Marinas should use “ Best Available
Technology”
• Consider “Environmental Fees”
NPDES – 2010
• Will see more and more marinas meeting the
NPDES regulations