20150212 Stormwater Agreement 02022017RESIDENTIAL
AGREEMENT TO MAINTAIN STORMWATER FACILITIES
BY AND BETWEEN
MOUNTAIN TERRACE BUILDERS, LLC
ITS HEIRS, SUCCESSORS, OR ASSIGNS
(HEREINAFTER "DEVELOPER ")
AND
City of Yelm, Washington
HEREINAFTER "JURISDICTION ")
The upkeep and maintenance of stormwater facilities and the implementation of pollution
source control best management practices (BMPs) is essential to the protection of water
resources. All property owners are expected to conduct business in a manner that promotes
environmental protection. This Agreement contains specific provisions with respect to
maintenance of stormwater facilities and use of pollution source control BMPs.
LEGAL DESCRIPTION:
A PORTION OF THE SOUTHWEST QUARTER OF THE NORTHWEST QUARTER OF SECTION 19,
TOWNSHIP 17 NORTH, RANGE 2 EAST, W.M., DESCRIBED AS FOLLOWS:
BEGINNING AT A POINT ON THE NORTH LINE OF SAID SUBDIVISION WHICH IS 256.65 FEET WEST
OF THE NORTHEAST CORNER THEREOF; THENCE WEST 204.66 FEET TO A POINT 943.65 FEET
EAST OF THE NORTHWEST CORNER OF SAID SUBDIVISION; THENCE SOUTH 37° 56' WEST 525
FEET, MORE OR LESS, TO THE NORTHEAST LINE OF COATES STREET IN THE TOWN OF YELM;
THENCE SOUTH 52° 04' EAST ALONG THE SAID NORTHEAST LINE OF COATES STREET 160 FEET;
THENCE NORTH 37° 56' EAST 652 FEET, MORE OR LESS, TO THE POINT OF BEGINNING;
EXCEPT THAT PORTION CONVEYED TO THE CITY OF YELM BY DEED RECORDED DECEMBER 5,
2008 UNDER AUDITOR'S FILE NO. 4049148;
IN THE COUNTY OF THURSTON, STATE OF WASHINGTON.
Whereas, the DEVELOPER has constructed improvements, including but not limited to,
buildings, pavement, and stormwater facilities on the property described above. In order to
further the goals of the Jurisdiction to ensure the protection and enhancement of water
resources, the Jurisdiction and the DEVELOPER hereby enter into this Agreement. The
responsibilities of each party to this Agreement are identified below.
DEVELOPER SHALL:
(1) Implement the stormwater facility maintenance program included herein as Attachment
"A."
(2) Implement the pollution source control program included herein as Attachment "B."
(3) Maintain a record (in the form of a log book) of steps taken to implement the programs
referenced in (1) and (2) above. The log book shall be available for inspection by
appointment at 14730 SR 507 SE, Yelm, WA 98597. The log book shall catalog the
action taken, who took it, when it was done, how it was done, and any problems
encountered or follow -on actions recommended. Maintenance items ( "problems ") listed
in Attachment "A" shall be inspected as specified in the attached instructions or more
often if necessary. The DEVELOPER is encouraged to photocopy the individual
checklists in Attachment "A" and use them to complete its inspections. These completed
checklists would then, in combination, comprise the log book.
(4) Submit an annual report to the Jurisdiction regarding implementation of the programs
referenced in (1) and (2) above. The report must be submitted on or before May 15 of
each calendar year and shall contain, at a minimum, the following:
(a) Name, address, and telephone number of the businesses, the persons, or the firms
responsible for plan implementation, and the person completing the report.
(b) Time period covered by the report.
(c) A chronological summary of activities conducted to implement the programs
referenced in (1) and (2) above. A photocopy of the applicable sections of the log
book, with any additional explanation needed, shall normally suffice. For any
activities conducted by paid parties, include a copy of the invoice for services.
(d) An outline of planned activities for the next year.
THE JURISDICTION SHALL:
(1) Provide technical assistance to the DEVELOPER in support of its operation and
maintenance activities conducted pursuant to its maintenance and source control
programs. Said assistance shall be provided upon request and as Jurisdiction time and
resources permit.
(2) Review the annual report and conduct a minimum of one (1) site visit per year to discuss
performance and problems with the DEVELOPER.
(3) Review this agreement with the DEVELOPER and modify it as necessary at least once
every three (3) years.
REMEDIES:
(1) If the Jurisdiction determines that maintenance or repair work is required to be done to
the stormwater facilities located in the subdivision, the Jurisdiction shall give the
DEVELOPER notice of the specific maintenance and /or repair required. The
Jurisdiction shall set a reasonable time in which such work is to be completed by the
persons who were given notice. If the above required maintenance and /or repair is not
completed within the time set by the Jurisdiction, written notice will be sent to the
DEVELOPER stating the Jurisdiction's intention to perform such maintenance and bill
the DEVELOPER for all incurred expenses.
(2) If at any time the Jurisdiction determines that the existing system creates any imminent
threat to public health or welfare, the Jurisdiction may take immediate measures to
remedy said threat. No notice to the persons listed in Remedies (1), above, shall be
required under such circumstances. All other DEVELOPER'S responsibilities shall
remain in effect.
(3) The DEVELOPER grants unrestricted authority to the Jurisdiction for access to any and
all stormwater system features for the purpose of performing maintenance or repair as
may become necessary under Remedies (1) and /or (2).
(4) The DEVELOPER shall assume responsibility for the cost of maintenance and repairs
to the stormwater facility, except for those maintenance actions explicitly assumed by
the Jurisdiction in the preceding section. Such responsibility shall include
reimbursement to the Jurisdiction within 90 days of the receipt of the invoice for any
such work performed. Overdue payments will require payment of interest at the current
legal rate for liquidated judgments. If legal action ensues, any costs or fees incurred by
the Jurisdiction will be borne by the parties responsible for said reimbursements.
This Agreement is intended to protect the value and desirability of the real property described
above and to benefit all the citizens of the Jurisdiction. It shall run with the land and be binding
on all parties having or acquiring any right, title, or interest, or any part thereof, of real property
in the subdivision. They shall inure to the benefit of each present or future successor in interest
of said property or any part thereof, or interest therein, and to the benefit of all citizens of the
Jurisdiction.
MOUNTAIN TERRACE BUILDERS, LLC,
a Washington Limited Liability Company
go
Michael Kempinski, Member
Dated this day �,� day of 20
Public Works Director, City of Yelm
STATE OF WASHINGTON }
i erc }S. S.
COUNTY OF }
On this day and year above personally appeared before me, Michael �prvlj�,tnsk who
executed the foregoing instrument and acknowledge the said instrument to be the free and
voluntary act and deed of said party for the uses and purposes therein mentioned and on oath
stated he is authorized to execute the said instrument.
Given under meUx` eftq icial seal this day of 20 j.
Kr. 1. 'l�
jR�! i DEBBERA L. HIRTLER
°� °T'�Ri'� ; Notary Pul#c in and for the State of
'" - • - �'= Washington, residing inclazAE&A
(Pa� OaBV_ 0 : My commission expires O �l /Q -/4'
//,If OP WASN"�����
STATE OF WASHINGTON }
)S. S.
COUNTY OF THURSTON )
On this day and year above personally appeared before me, , who
executed the foregoing instrument and acknowledge the said instrument to be the free and
voluntary act and deed of said Municipal Corporation for the uses and purposes therein
mentioned and on oath stated he is authorized to execute the said instrument.
Given under my hand and official seal this day of , 20
Notary Public in and for the State of
Washington, residing in
My commission expires
ATTACHMENT "A"
TYLER TERRACE
STORMWATER FACILITY MAINTENANCE
GUIDE
December 7, 2016
INTRODUCTION
What is Stormwater Runoff?
When urban and suburban development covers the land with buildings, houses, streets and parking lots,
much of the native topsoil, duff, trees, shrubs and grass are replaced by asphalt and concrete. Rainfall
that would have soaked directly into the ground instead stays on the surface as stormwater runoff making
its way into storm drains (including man -made pipes, ditches, or swale networks), stormwater ponds,
surface and groundwater, and eventually to Puget Sound.
What is a Storm Drain System and how does it work?
The storm drain system for most developments includes components that carry, store, cleanse, and
release the stormwater. These components work together to reduce the impacts of development on the
environment. These impacts can include flooding which results in property damage and blocked
emergency routes, erosion which can cause damage to salmon spawning habitat, and pollution which
harms fish and /or drinking water supplies.
The storm drain system provides a safe method to carry stormwater to the treatment and storage area.
Swales and ponds filter pollutants from the stormwater by physically settling out particles, chemically
binding pollutants to pond sediments, and biologically converting pollutants to less - harmful compounds.
The ponds also store the treated water, releasing it gradually to a nearby stream or to groundwater. The
various components of storm drain systems are described in the glossary.
What Does Stormwater Runoff have to do with Water Quality?
Stormwater runoff needs to be treated because it carries litter, oil, gasoline, fertilizers, pesticides, pet
wastes, sediments, and anything else that can float, dissolve or be swept along by the moving water. Left
untreated, polluted stormwater can reach nearby waterways where it can harm and even kill aquatic life.
It can also pollute groundwater to the extent that it must be treated before it can be used for drinking,
which has actually happened in Thurston County. Nationally, stormwater is recognized as a major threat
to water quality. Remember to keep everything out of stormwater systems except the rainwater they are
designed to collect.
Your Neighborhood Stormwater Facility
Stormwater facilities can be attractive as well as functional. They can provide both active and passive -
use recreation areas and open space for wildlife. Perhaps you've noticed a wet pond or dry pond in your
neighborhood. These different types of ponds are designed for different purposes. For example, wet
ponds primarily provide treatment of stormwater. They also provide good cover and habitat for birds and
small mammals, making them fine "wildlife preserves" Dry ponds or infiltration ponds are designed to
provide storage for stormwater and gradually release it downstream or allow it to filter into the ground.
These types of ponds can be maintained as grassy play areas, and may even be modified to house more
formal play equipment.
Who is Responsible for Maintaining Stormwater Facilities?
All stormwater facilities need to be maintained. Regular maintenance ensures proper functioning and
keeps the facility visually appealing. This Stormwater Facility Maintenance Guide was designed to help
explain how stormwater facilities work and provide user - friendly, straightforward guidance on how to
maintain them.
As a homeowner or homeowner's association, you are responsible for regularly maintaining privately
owned ponds, catch basins, pipes and other drainage facilities within your subdivision. Stormwater
facilities located in public right -of -ways are maintained by local governments.
3
How to Use the Stormwater Facility Maintenance Guide
This Maintenance Guide includes a Site Plan specific to your subdivision and a Facility Key that identifies
the private stormwater facilities you are responsible for maintaining. A "Quick List" of maintenance
activities has also been included to help you identify the more routine needs for your facility.
This guide includes:
A Glossary that defines terms and explains functions of the various components of stormwater drainage
systems;
A comprehensive Maintenance Checklist that provides specific details on required maintenance;
A section on Pollution Prevention Tips that lists ways to protect water quality and keep storm drain
systems functioning smoothly;
And a section on Resources that directs you to sources of more information and technical assistance.
A Regional Approach to Stormwater Management
The Cities of Lacey, Olympia and Tumwater together with Thurston County are taking steps to educate
and involve area residents in water quality issues and stormwater management. Stormwater runoff is a
widespread cause of water quality impairment and stream degradation. The jurisdictions are working
together with residents, businesses, community groups and schools to address this problem.
This Guide focuses on providing information on ways that residents and businesses can reduce
stormwater impacts through pollution prevention and proper facility maintenance. Everyone needs to
help keep waterways and groundwater clean. With proper management and common sense we can
continue to enjoy clean, safe streams and drinking water
YOUR STORMWATER FACILITIES
This section consists of two parts that are to be used together: the Site Plan and the Facility Key. Look
on the site plan and identify the numbers which denote a feature of the system. Then look on the facility
key to see what that feature is called and which checklist applies.
SITE PLAN
Developer or Engineer to add site plan here (can either be a customized drawing or copy of the
stormwater facility details from the set of as built plans).
FACILITY KEY
The stormwater facility in your neighborhood is comprised of the following elements:
Type of feature & Checklist Name
Location on Site Plan
Pond
Catch Basins, Manholes, and Inlets
Fences, Shrubbery Screens, and Gates
Grounds and Landscaping
Conveyance Pipes, Ditches, and Swales
Drywells, French Drains, or Downspouts
Access Roads and Easements
QUICK LIST
The following list is an abbreviated checklist of the most common types of maintenance you should have
to do. Please try and go over this checklist after heavy rains. This is a bare minimum and should be
done in conjunction with the other checklists in order to make your maintenance program effective.
❑ Check catch basin grates to see that they are not clogged or broken. Remove twigs, leaves, or other
blockages. Replace the grate if it is broken.
❑ Check inlet and outlet pipes for blockages. Clear all blockages.
❑ Check berms and pond walls for erosion or caved in areas. Contact for guidance.
❑ Check rip rap rocks at the inlets and outlets. If they are silted in or eroded away, replace them.
MAINTENANCE CHECKLISTS
The Maintenance Checklists in this packet are for you to use when checking the stormwater facilities in
your neighborhood. This packet has been customized so that only the checklists for your facilities are
included. If you feel you are missing a checklist, or you have additional facilities not identified or
addressed in this packet, please contact your developer or local jurisdiction.
The checklists are in a table format for ease of use and brevity. Each checklist tells you what part of the
feature to check, how often to check, what to check for, and what to do about it. Log sheets are included
toward the end of the chapter to help you keep track of when you last surveyed the storm drainage
system.
Although it is not intended for the maintenance survey to involve anything too difficult or strenuous, there
area few tools that will make the job easier and safer. These tools include:
• A flashlight.
• A long pole or broom handle.
• Some kind of pry bar or lifting tool for pulling manhole and grate covers.
• Gloves.
A listing of resources is included in the next Chapter. Here you will find the phone numbers of the
agencies referred to in the tables, as well as the contractor and consultants that designed and
constructed your facilities.
SAFETY WARNING: Due to OSHA regulations you should never stick your head or any part of
your body into a manhole or other type of confined space. When looking into a manhole or catch
basin, stand above it and use the flashlight to help you see. Use a pole or broom handle that is
long enough when you are checking sediment depths in confined spaces. NO PART OF YOUR
BODY SHOULD BREAK THE PLANE OF THE OPEN HOLE.
Ponds
There are essentially three kinds of ponds. treatment ponds, infiltration ponds, and detention ponds.
Although each pond has unique maintenance requirements, there are also many things they have in
common.
Part of Pond
to Check
When to
Check it
What to Check For
What to Do
Entire Pond
Quarterly
Dumping of yard wastes such
Remove trash and debris and dispose
as grass clippings and
of properly. Contact your local Waste
branches into basin.
Management department for disposal
Presence of glass, plastic,
information.
metal, foam, and coated
paper.
Entire Pond
Quarterly
Any vegetation which may
Remove invasive or noxious
constitute a hazard to the
vegetation. Do not spray chemicals on
public, such as tansy ragwort,
vegetation without obtaining guidance
poison oak, stinging nettles,
from WSU Cooperative Extension and
devilsclub.
approval from the City or County.
Entire Pond
Quarterly
Presence of chemicals such
First, try and locate the source of the
as natural gas, oil, and
pollution. Then call the Moderate Risk
gasoline, obnoxious color,
Waste program at Thurston County
odor, or sludge.
Environmental Health to report the
hazard.
Entire Pond
Quarterly
Sparse, weedy, or overgrown
For grassy ponds, selectively thatch,
grass in grassy
aerate, and re -seed ponds. Grass
(dry /infiltration) ponds.
should be kept under 8 inches high.
Presence of invasive species
For wetland ponds, hand -plant
or sparse growth of plants in
nursery -grown wetland plants in bare
wetland ponds.
areas. Contact WSU Cooperative
Extension for guidance on invasive
species. Pond bottoms should have
uniform dense coverage of desired
plant species.
Entire Pond
Quarterly
Any evidence of rodent holes
Destroy rodents and repair the dam or
if your facility is acting as a
berm. Contact the Thurston County
dam or berm. Water should
Health Department for guidance.
not be able to flow through
rodent holes.
Entire Pond
Quarterly
Insects such as wasps and
Destroy or remove insects. Contact
hornets interfering with
WSU Cooperative Extension for
maintenance activities, or
guidance.
mosquitoes becoming a
nuisance.
Entire Pond
Annually
Ensure that trees are not
Prune tree limbs to allow for
interfering with maintenance
maintenance. Some trees may be cut
(i.e., mowing, silt removal, or
for firewood.
access.)
10
Inlet
Annually
Make sure that the rip rap
Replace rocks or clean out sediment.
under the inlet pipe is intact
and that no native soil is
exposed. Also check for
accumulations of sediment
more than % the height of the
rocks.
Outlet
Quarterly
The bar screen over the
Replace screen if it is not attached.
outlet should be intact and
Remove any trash or debris and
clear of debris. Water should
dispose of properly. Clean out the end
flow freely through the outlet
of pipe if necessary. Contact your
pipe.
local Waste Management department
for disposal information.
Side Slopes
Annually
Check around inlets and
Try and determine what has caused
outlets for signs of erosion.
the erosion and fix it. Stabilize slopes
Check berms for signs of
by reinforcing the slope with rock,
sliding or settling. Action is
planting grass, or compacting the soil.
needed where eroded
Contact WSU Cooperative Extension
damage is over 2 inches
for guidance on slope reinforcement.
deep and where there is
potential for continued
erosion_
Storage Area
Annually
Check to see if sediment is
Clean out the sediment and re -seed
building up on the pond
the pond if deemed necessary to
bottom. A buried or partially
improve infiltration and control erosion.
buried outlet structure or very
Contact your local jurisdiction's
slow infiltration rate probably
stormwater maintenance division for
indicates significant sediment
technical assistance.
deposits.
Dikes
Annually
Any part of the dike which
Build the dike back to the original
has settled significantly.
elevation.
Emergency
Annually
Check to see that the rip rap
Replace rocks so that all native soil is
Overflow /Spill
protective area is intact. If
covered.
way
any exposed native soil is
present you should repair it.
Emergency
One Time
Side of pond has no rip rap
A rip rap spillway should be installed.
Overflow /Spill
protective area to prevent
Contact your local jurisdiction's
way
erosion during emergency
stormwater maintenance division for
overflows.
guidance. If the facility is less than two
years old, this should be the
contractor's responsibility.
Sediment
Quarterly
Ensure that sediment and
Clean out the sump area.
Trapping Area
debris do not obstruct water
flow into the infiltration area.
Sediment
One Time
stormwater should not enter
the infiltration area directly
Add a sediment trapping area by
constructing a sump for settling of
11
Trapping Area
without some method of
solids. This settling area should be
settling out solids.
separate from the rest of the facility.
Contact your local jurisdiction's
stormwater maintenance division for
technical assistance. If the facility is
less than a year old, this should be the
contractor's responsibility.
12
Catch Basins and Inlets
These structures are typically located in the streets and public rights -of -way. Local jurisdictions are
responsible for routine maintenance of the pipes and catch basins in rights -of -way, while the homeowners
association is responsible for keeping the grates clear of debris in all areas as well as pipes and catch
basins in private areas.
Part of Catch
When to
What to Check For
What to Do
Basin to
Check it
Check
Catch basin
During and
Trash or debris accumulating in
Remove blocking trash or debris
opening
after major
front of the catch basin opening
with a rake and clean off the
storms
and not allowing water to flow in.
grate.
Catch basin
Quarterly
Sediment or debris in the basin
Clean out the catch basin of
should be kept under 50% of the
sediment and debris. Contact
depth from the bottom of the
your local jurisdiction's
pipe to the bottom of the basin..
stormwater maintenance division
Use a long stick or broom handle
for technical assistance.
to poke into sediment and
determine depth.
Inlet and outlet
Quarterly
Trash or debris in the pipes
Clean out inlet and outlet pipes of
pipes
should not be more than 115 of
trash or debris.
its height. Also, there should not
be any tree roots or other
vegetation growing in the pipes.
Inlet and outlet
Annually
There should be no cracks wider
Repair cracks or replace the
pipe joints
than % inch and longer than 1
joints. Contact your local
foot at the joint of any inlet or
jurisdiction's stormwater
outlet pipe. Also check for
maintenance division for technical
evidence of sediment entering
assistance.
the catch basin through cracks.
Grate
Quarterly
The grate should not have
Replace the grate.
cracks longer than 2 inches.
There should not be multiple
cracks.
Frame
Quarterly
Ensure that the frame is sitting
Repair or replace the frame so it
flush on top of the concrete
is flush with the slab.
structure (slab). A separation of
more than % inch between the
frame and the slab should be
corrected.
Catch basin
Annually
Inspect the walls of the basin for
Replace or repair the basin.
cracks wider than % inch and
Contact a professional engineer
longer than 3 feet. Also check
for evaluation.
for any evidence of sediment
entering the catch basin through
cracks. Determine whether or
not the structure is sound.
13
Catch basin
Quarterly
There should be no chemicals
such as natural gas, oil, and
gasoline in the catch basin.
Check for obnoxious color, odor,
or oily sludge.
Clean out catch basin. Contact
your local jurisdiction or Thurston
County Environmental Health if
you detect a color, odor, or oily
sludge.
Oil/Water
Quarterly
Water surface in catch basin has
Remove the catch basin lid and
separator
significant sludge, oil, grease, or
skim off oil layer. Pour oil into a
(downturned
scum layer covering all or most
disposable container, seal
elbow or "T" in
Quarterly
of the water surface.
container, wrap securely in
catch basin)
ensure that it blocks easy
newspaper, and place in trash.
screen
entry to the facility. Make
Water surface should be clear of
sure erosion hasn't created
oily layer.
Pipe Elbow
Quarterly
Top or bottom of pipe appear to
Remove the catch basin lid and
Shrubbery
Quarterly
have broken off. Check for any
examine the pipe for damage. If
screen
apparent damage and check to
broken, hire a contractor to
see if it's plumb.
replace pipe in accordance with
Wire Fences
Annually
Look along the length of the
approved plans on file with your
fence and determine if it is out
local jurisdiction.
Fencing, Shrubbery Screens, and Gates
Fences and shrubbery screens aren't typically required for stormwater ponds. If the slopes of the sides
are too steep, usually some kind of barricade is constructed.
Part of
When to
What to Check For
What to Do
Fencing,
Check it
Shrubbery, or
Gate to Check
Fence or
Quarterly
Inspect the fence or screen to
Mend the fence, repair erosion, or
shrubbery
ensure that it blocks easy
replace the shrubs to form a solid
screen
entry to the facility. Make
barrier.
sure erosion hasn't created
an opening under fence.
Shrubbery
Quarterly
Shrubbery should not be
Trim and weed shrubbery to provide
screen
growing out of control or
appealing aesthetics. Do not use
infested with weeds
chemicals to control weeds.
Wire Fences
Annually
Look along the length of the
Straighten posts and rails if
fence and determine if it is out
necessary.
of alignment.
Wire Fences
Annually
Missing or loose tension wire.
Replace or repair tension wire so it
holds fabric.
Wire Fences
Annually
Missing or loose barbed wire.
Replace or repair barbed wire so
that it doesn't sag between posts.
Wire Fences
Annually
k for rust or scaling.
Paint or coat rusting or scaling parts
In
with a protective coating.
14
Wire Fences
Quarterly
Ensure that there are no
holes in the fabric or fencing.
Repair holes so that there are no
openings in the fabric or fencing.
Gate
Quarterly
Ensure that the gate is not
Repair or replace the gate to allow
broken, jammed, or missing
entry of people and maintenance
and that it opens easily.
equipment. If a lock is used, make
sure your local jurisdiction's
stormwater maintenance staff have
a key.
15
Conveyance Pipes, Ditches, and Swales.
Part of
System to
Check
When to
Check it
What to Check For
What to Do
Pipes
Annually
Accumulated sediment should
Clean out pipes of all sediment and
not exceed 20% of the
debris. Remove all vegetation so
diameter of the pipe.
that water flows freely through
Vegetation should not reduce
pipes. Repair or replace pipe. For
free movement of water
long sections of underground pipe
through pipes. Ensure that the
contact your local jurisdiction's
protective coating is not
stormwater maintenance division for
damaged and rusted. Dents
technical assistance.
should not significantly impede
flow. Pipe should not have
major cracks or tears allowing
water to leak out.
Open ditches
Quarterly
There should not be any yard
Remove trash and debris and
waste or litter in the ditch.
dispose of them properly.
Open ditches
Annually
Accumulated sediment should
Clean out ditch of all sediment and
not exceed 20% of the depth
debris. Contact your local
of the ditch.
jurisdiction's stormwater
maintenance division for information
on sediment disposal.
Open ditches &
Annually
Check for vegetation (e.g.,
Clear blocking vegetation so that
Swales
weedy shrubs or saplings) that
water flows freely through ditches.
reduces the free movement of
Grassy vegetation should be left
water through ditches or
alone.
swales.
Open ditches &
Quarterly
Check around inlets and
Eliminate causes of erosion.
Swales
outlets for signs of erosion.
Stabilize slopes by using
Check slopes for signs of
appropriate erosion control
sloughing or settling. Action is
measures (e.g., reinforce with rock,
needed where eroded damage
plant grass, compact soil.)
is over 2 inches deep and
where there is potential for
continued erosion.
Open ditches &
Annually
Native soil beneath the rock
Replace rocks to design standard.
Swales
splash pad, check dam, or
lining should not be visible.
Swales
Quarterly
Grass cover is sparse and
Aerate soils and reseed and mulch
weedy, or areas are overgrown
bare areas_ Keep grass under 8
with woody vegetation.
inches high. Remove woody
growth, recontour, and reseed as
necessary.
Swales
Quarterly
Swale has been filled in or
If possible, speak with homeowner
blocked by shed, woodpile,
and request that the swale area be
shrubbery, etc.
restored. Contact your local
jurisdiction to report problem if not
rectified voluntarily.
16
Swales
Annually
Water stands in swale or flow
A survey may be needed to check
Grounds to
Check it
velocity is very slow.
grades. Grades need to be in 1 -5%
Check
Stagnation occurs.
range if possible. If grade is less
Landscaped
Quarterly
Weeds growing out of control in
than 1 %, underdrains may need to
Areas
landscaped area.
be installed. Contact your local
jurisdiction's stormwater
Landscaped
Quarterly
Check for any presence of
maintenance division for technical
Areas
poison ivy or other poisonous
assistance
Grounds and Landscaping
Part of
When to
What to Check For
What to Do
Grounds to
Check it
Check
Landscaped
Quarterly
Weeds growing out of control in
Pull weeds by hand, if possible, to
Areas
landscaped area.
avoid using chemical weed
controls.
Landscaped
Quarterly
Check for any presence of
Remove poisonous vegetation or
Areas
poison ivy or other poisonous
insect nests that are present in
vegetation or insect nests.
landscaped area.
Landscaped
Quarterly
There should not be any yard
Remove and dispose of litter
Areas
waste or litter in landscaped
properly
areas.
Landscaped
Quarterly
Noticeable rills are seen in
Identify the causes of erosion and
Areas
landscaped areas.
take steps to slow down or
disperse the water. Fill in
contour, and seed area.
Trees and
Annually
Limbs or parts of trees or shrubs
Trim trees and shrubs to restore
shrubs
that are split or broken.
shape. Replace severely
damaged trees and shrubs.
Trees and
Annually
Trees or shrubs that have been
Replant trees or shrubs,
shrubs
blown down or knocked over.
inspecting for injury to stem or
roots. Replace if severely
damaged.
Trees and
Annually
Trees or shrubs which are not
Place stakes and rubber - coated
Shrubs
adequately supported or are
ties around young trees /shrubs
leaning over, causing exposure
for support.
of the roots.
17
Access Roads and Easements.
Area to Check
When to
What to Check For
What to Do
Downspout
Check it
Water overflows from the
First try cleaning out the gutters and
General
One Time
Check to determine if there is
If there is not enough access,
enough access to your
check with your local jurisdiction to
stormwater facilities for
determine whether an easement
maintenance vehicles.
exists. If so, a maintenance road
may need to be constructed there.
Access road
Quarterly
Debris which could damage
Clear all potentially damaging
vehicle tires (glass or metal).
debris.
Access road
Annually
Any obstructions which reduce
Clear along and over roadway so
clearance above and along the
there is enough clearance.
road to less than 14 feet.
acid solutions instead of highly toxic
Road surface
Annually
Check for potholes, ruts, mushy
Add gravel or remove wood as
spots, or woody debris that
necessary.
limits access by maintenance
vehicles.
Shoulders and
Annually
Check for erosion along the
Repair erosion with additional soil
ditches
roadway.
or gravel.
Drywells, French Drains, or Downspouts
Part of system
to Check
When to
Check it
What to Check For
What to Do
Downspout
Annually
Water overflows from the
First try cleaning out the gutters and
gutter or downspout during
downspouts. If this doesn't solve the
rain.
problem you may need to install a
bigger drywell. Contact your local
jurisdiction's stormwater maintenance
division for technical assistance.
Roof
Annually
Moss and algae are taking
Disconnect the flexible part of the
over the shadier parts of the
downspout that leads to the drywell.
shingles.
Then perform moss removal as
desired. Pressure wash or use fatty
acid solutions instead of highly toxic
pesticides or chlorine bleach. Install a
zinc strip as a preventative.
18
RESOURCE LISTING
If you are unsure whether a problem exists, please contact your local jurisdiction at one of the numbers
below and ask for Technical Assistance.
Contact Numbers:
Olympia Maintenance - 753 -8220
Olympia Water Resources - 753 -8321 or 753 -8598 (24 Hour Number).
Pacific Disposal - 352 -2046
Thurston Conservation District - 754 -3588
Thurston County Community & Environmental Programs - 754 -4111
Thurston County Environmental Health (Moderate Risk Waste) - 754 -4111
Thurston County Solid Waste - 786 -5136
Thurston County Storm & Surface Water - 754 -4681
Olympia Public Works — 753 - -8362
WSU Cooperative Extension - 786 -5445
Developer Information:
MOUNTAIN TERRACE BUILDERS, L.L.C.
14307 State Route 507 SE
Yelm, Washington 98597
(360) 507 -0868
Contact: Mike Kempinski, Member
LOG SHEET
Use log sheets to keep track of when maintenance checks occur and what items, if any, are repaired or
altered. The completed sheets will serve as a record of past maintenance activities and will provide
valuable information on how your facilities are operating. This information will be useful for future
requirements regarding the types of facilities that are installed. It helps to keep all log sheets in a
designated area so they can be easily accessed by others.
There are copies of the log sheet in your packet to last one year based on four quarterly and one annual
check. There is an additional log sheet in your packet that should be preserved as an original from which
to make additional copies as they are needed in the future. If you run out of blank sheets, contact your
local jurisdiction and request more.
19
Date Checked
Checked By
Name:
Position in HOA:
Address: City: State: Zip:
Phone Number.
Part of Facility
Checked
Observations (List things that
should be done)
Follow -up Actions Taken
Date Action
Taken
20
ATTACHMENT "B"
POLLUTION PREVENTION FOR HOMEOWNERS
PURPOSE
Many products and practices commonly used in and around our houses are hazardous to both ourselves
and the environment. Many of these products can end up in our stormwater systems and groundwater.
This document gives alternatives, where possible, for those types of products and practices. The Best
Management Practices (BMPs) described here, include "good housekeeping" practices that everyone can
use.
RECOMMENDED POLLUTION CONTROL PRACTICES FOR HOMEOWNERS
It has been said that the average home today contains more chemicals than the average chemical lab of
100 years ago. When many of these chemicals are used industrially, they can be subject to various health
and safety standards; yet these same substances are used freely and often carelessly in our homes.
The BMPs in this section are divided into four categories: Household Hazardous wastes, Pesticides,
Remodeling, and Septic Maintenance. Each section includes information on available alternatives.
HOUSEHOLD HAZARDOUS WASTES
Many of the cleaning agents, solvents, polishes, etc. used commonly in the home are considered
hazardous. These products may be toxic, corrosive, reactive, flammable, and /or carcinogenic. It is critical
that these products are handled with care and properly disposed. A list of some common household
hazardous materials is presented in Table 1.
In addition, many hazardous household chemicals persist for long periods of time in the environment.
Manufacturers may truthfully state that a product is "biodegradable "; most products are biodegradable,
but what is important is the rate at which they are broken down and the products they are broken down
into. The term "biodegradable" on its own is misleading at best, unless the product is rapidly degraded
into harmless substances.
It is important to note here that the term "biodegradable" currently has no legal definition in this state. This
means that any product can use this term according to the manufacturer's own definition. This definition
may not be at all similar to the consumer's perception.
The following ideas will help you reduce the risks of stormwater and ground water contamination from
many household products:
21
HOUSEHOLD PRODUCT MANAGEMENT
1. Read the label of products before you buy them. Toxic product labels will carry many warnings.
Either bypass such products or buy them in small quantities. If you cannot use all of the product,
try to give it away instead of disposing of it. Thurston County periodically facilitates product
exchanges for leftover paints and other hazardous wastes. Call the Thurston County Health
Department at 754 -4111 for more information.
2. Buy only those detergents that contain little or no phosphorus. Phosphorus can cause algae
blooms if it is washed into lakes, streams, Most detergents which are low or phosphate free are
labeled as such.
3. Use no more than the manufacturer's suggested amount of any cleanser. More is not necessarily
better.
4. Products such as oven cleanser, floor wax, furniture polish, drain cleaners, and spot removers
often contain chemicals that are toxic. Buy the least toxic product available, and use a non -toxic
substitute if one can be found. Ovens, for example can be cleaned by applying table salt to spills,
then scrubbing with a solution of washing soda and water. Table 2 lists substitutes for many
commonly used household products.
If it is necessary to use a product that contains toxic chemicals, use the product only as directed.
Do not combine products, as they may become more dangerous when mixed (example: mixing
chlorine bleach and ammonia produces dangerous gases). Use eye wear and rubber gloves as
appropriate.
Contact the Hazardous Substance Hotline at 1- 800 - 633 -7585 if you have any questions regarding
disposal of a product or empty container. The County has both hazardous waste collection days
and permanent facilities where residents can bring hazardous wastes. Call the Thurston County
Health Department at 754 -4111 for more information.
5. Chemicals left over from some activities, such as photography and auto repair, are hazardous
and should not be flushed down the sink. This is especially important if your home is hooked up
to a septic system. Toxic chemicals can kill the bacteria in the tank that treat sewage and pollute
water supply wells.
6. Be sure that all containers are clearly marked.
7. Common (not automobile) batteries are one of the largest sources of heavy metals (such as lead,
nickel, cadmium, and mercury) found in landfills. Instead of throwing them away, dispose of them
at a hazardous waste collection site.
AUTOMOTIVE USAGE, CARE AND MAINTENANCE
From a waste management standpoint, automobile maintenance is best done by professionals at
facilities designed to handle, store, and dispose of the waste products correctly. Many of these
facilities do an excellent job of dealing with waste oils, antifreezes, other fluids, batteries and tires.
They often charge a small fee to cover the added expenses, but it's worth it. However if you
repair your car at home, please consider these helpful tips:
1. Cars should be serviced regularly. Any leaky lines or valves should be replaced.
2. Dumping oil, degreasers, antifreeze, and other automotive liquids into a stream or a storm drain
violates city, county and state laws or ordinances. Do not dump them onto the ground because
they will end up in stormwater runoff or in groundwater. Do not use oil to reduce dust levels on
unpaved areas. Instead, recycle used oil and antifreeze. Keep them in separate containers. Call
22
the Recycling Hotline at 1- 800 - RECYCLE or call the Thurston County Health Department for the
location of the nearest recycling center, or call your local automotive service centers to see if they
take oil for recycling. Some may also take used oil filters.
3. Wrap empty oil or antifreeze containers in several layers of newspaper, tie securely and place in
a covered trash can. Antifreeze is sweet- tasting, but poisonous to people, fish, pets and wildlife.
4. Sweep your driveway instead of hosing it down. Fluids and heavy metals associated with
automobiles can build up on driveway surfaces and be washed into local surface or groundwater
when driveways are hosed down.
5. When washing vehicles, do so over your lawn or where you can direct soapsuds onto the lawn or
another vegetated area to keep the soaps from washing into the storm drain system or local
surface water. Your stormwater pond cannot cleanse soapy water from washed cars.
6. Small spills of oil and other fluids can be absorbed by using materials such as kitty litter or
sawdust. Wrap the used kitty litter and any contaminated soil in a plastic bag and then place it in
the garbage.
If a spill reaches surface water, you must notify the nearest regional office of the Department of
Ecology Immediately! Southwest Region - Olympia 753 -2353 (24 -hour) or call 911. There are
fines for failure to notify the appropriate agency when a spill occurs.
7. De -icing chemicals (various types of salt) can harm concrete less than three years in age, burn
vegetation, and be corrosive to cars and other metal objects. Deicing chemicals and their
additives can be toxic. Cyanide is formed from the breakdown of a common anti - caking agent
used in deicing chemicals.
Urea salts are an alternative to other types of salt de- icers, but great care must be used in
applying them. These salts contain large quantities of nitrogen, which can severely burn plants
and encourage algae growth in lakes and /or Puget Sound, if over - applied.
8. The use of these chemicals should be minimized or avoided. Instead, shovel walks clear and
apply a dusting of sand to improve footing.
23
Table 1 Hazardous Household Substances List
Auto, Boat and equipment
Repair and Remodeling
Cleansing Agents
Maintenance
1.
Adhesives, glues, cements.
1.
Oven cleaners
1.
Batteries
2.
Roof coatings, sealants.
2.
Degreasers and spot
2.
Waxes and cleansers
removers
3.
Caulking and sealants.
3.
Paints, solvents and thinners
3.
Toilet, drain and septic tank
4.
Epoxy resins.
cleaners
4.
Additives
5.
Solvent -based paints.
4.
Polishes, waxes and
5.
Gasoline
strippers
6.
Solvents and thinners.
6.
Flushes
5.
Deck, patio and chimney
7.
Paint removers and strippers.
cleaners
7.
Auto repair materials
6.
Solvent cleaning fluids
8.
Motor oil
9.
Diesel oil
10.
Antifreeze
Pesticides
Hobby and Recreation
Miscellaneous
1.
Insecticides
1.
Paints, thinners and solvents
1.
Ammunition
2.
Fungicides
2.
Chemicals (photo and pool
2.
Asbestos
3.
Rodenticides
3.
Glues and cements
3.
Fireworks
4.
Molluscicides
4.
Inks and dyes
5.
Wood preservatives
5.
Glazes
6.
Moss retardants
6.
Chemistry sets
7.
Herbicides
7.
Bottled gas
8.
Fertilizers
8.
White gas
9.
Charcoal starter fluid
Source: Guidelines for Local Hazardous Waste Planning, Ecology, No. 87 -18 1987.
24
Table 2 Non -Toxic or Less Toxic Alternatives to Toxic Products
Hazardous Product
Alternative(s)
Air fresheners
Set out a dish of vinegar or simmer cinnamon and cloves or
set out herbal bouquets or potpourri in open dishes or burn
scented candles.
Bleach
Borax or oxygen bleaches or reduce bleach by % and add
- 112C baking soda, or let clothes dry in the sun.
Brass polish.
Worcestershire sauce.
Chrome polish
Apple cider vinegar or a paste of baking soda and water or a
lemon
Coffee pot cleaner
Vinegar.
Coffee stains
Moist salt paste.
Copper cleaner
Mix lemon juice and salt or use tomato catsup
Drain cleaner
Use a plunger followed by % C. baking soda mixed in % C.
vinegar. Let sit 15 minutes, pour down 2 qt. boiling water.
Furniture polish
Linseed, olive or almond oils or a mixture of 3 parts olive oil
to 1 part white vinegar or a mixture of 1 Tbs. Lemon oil and 1
pint mineral oil.
Garbage disposal deodorizer
Used lemon rind or baking soda.
Glass cleaner
Mix 2 Tbs. vinegar with 1 quart water.
Grease remover
Make a paste of borax on a damp cloth.
Ink stain remover
Spray with leftover non - aerosol hair spray before washing.
Laundry soap
Borax, baking soda or washing soda
Linoleum floor cleaner
1 C. white vinegar in 2 gals. water.
Mildew remover
Equal parts vinegar and salt.
Mothballs
Cedar chips or blocks, or use dried tansy, lavender or
peppercorns in drawers and closets.
Oil spills
Kitty litter, sawdust.
Oil stain removal
White chalk rubbed into the stain prior to washing.
Oven cleaner
Pour lots of sit on fresh spills and scrape off after the oven
cools. A soda water solution will cut grease. Paint ammonia
on spills with a paintbrush, then rinse off.
Paint brush softener
Hot vinegar.
25
Table 2 Non -Toxic or Less Toxic Alternatives to Toxic Products (Cont.)
Hazardous Product
Alternative(s)
Paint stripper
Use mechanical sanding instead of chemical strippers.
Paint/grease remover
Wear gloves or use baby oil.
Pet odor removal
Cider vinegar.
Pitch or sap remover
Butter, margarine or vegetable shortening.
Porcelain stain remover
Baking soda
Refrigerator deodorizer
Open box of baking soda.
Rug /carpet cleaner
(General)Use a soap -based non - aerosol rug shampoo,
vacuum when dry. (Spots)Pour on club soda or sprinkle
cornmeal or cornstarch on the rug, let sit for at least 30
minutes, then vacuum.
Rust removal
Lemon juice plus salt plus sunlight.
Rusty bolt remover
Carbonated beverage.
Scorch mark remover
Grated onion.
Scouring powder
Baking soda or a non - chlorine scouring powder.
Silver polish
Soak silver in warm water with 1 Tbs. soda, 1 Tbs. salt
and a piece of aluminum foil.
Stainless steel polish
Mineral oil.
Toilet bowl cleaner
Paste of borax and lemon juice.
Tub and the cleaner
114 C. soda and % C. white vinegar mixed with warm
water.
Upholstery spot remover
Club soda.
Water mark remover
Toothpaste.
Water softener
114 C, vinegar.
26
PESTICIDES' AND FERTILIZERS
Pesticides (such as insecticides and herbicides) and fertilizers are commonly used by homeowners in
their quest for bigger, healthier plants and greener, lusher lawns. These chemicals are often overused.
Homeowners often apply too much chemical at the wrong time, such as before heavy rains or any time
the plants will not be able to absorb all the chemicals. These chemicals are easily introduced into
stormwater runoff and can cause algae blooms (fertilizers) or kill off aquatic organisms (pesticides).
Fertilizer management
Fertilizing a lawn can be done in an environmentally sensitive manner. Here are some ideas:
1. Before fertilizing, test your soil's pH. This can be easily done by using kits that are available, or
through tests provided by WSU Cooperative Extension. Use only the recommended amount of
fertilizer, and add any soil amendments, such as lime, that are recommended in your test results.
2. Use fertilizers that are appropriate for your area, and for the type of plants you are growing. Work
the fertilizer into the soil directly around the plants drip line. By incorporating the fertilizer in the
soil, there will be less likelihood of contaminated runoff. Contact the Thurston Conservation
District to find out this information.
3. Water before fertilizing. Water enough to dampen the ground thoroughly, but not enough to cause
surface runoff. Dampening the soil prevents fertilizer from being washed from the surface of dry
soil in the first rain or watering after application
4. Many soils can benefit from the use of organic fertilizers such as compost or peat. Not only do
these substances add nutrients to soil, they also increase the porosity of the soil and increase its
ability to hold water.
5. Slow release fertilizers (which are generally resin- coated) can be used in addition to organic
fertilizers. They are not mobile in the soil, and are only applied once, which saves work.
Integrated pest management
Rather than bringing out the sprayer whenever a pest infestation occurs in the garden consider using
Integrated Pest Management (also known as IPM). IPM emphasizes the evaluation of all factors including
environmental effects before chemicals are applied. Pesticides should only be used as a last resort.
Some of the tactics that can be used to decrease or eliminate the use of pesticides include:
Use of Natural Predators, Pathogens: Because chemical sprays generally kill many beneficial insects
instead of just the target pest, it may be necessary to introduce natural predators back into the garden.
Ladybugs, lacewings, predatory wasps, and nematodes are all commercially available. Garter snakes
and toads are also predators and should not be eliminated from the garden.
There are some bacteria, viruses, and insect parasites that are specific to pests and will not harm other
insects or animals. A commonly used bacterium in the Puget Sound area is Bacillus thuringiensis (Bt),
which is intended to control infestations of tent caterpillars. Products containing Bt are available at your
nursery.
Habitat Changes: Many times a change of habitat can control pest infestations. Removal of old tires
can cut down on the mosquito population by removing a convenient water - filled location for them to breed
1 As used here, the word pesticide can mean any herbicide, insecticide, rodenticide, miticide, or other types of chemicals used in
the same manner.
27
in. Crop rotation, even in a small garden, can reduce the number of pest infestations. Removing last
year's leaves from under rose bushes can cut down on the incidence of mildew and blackspot, as these
fungi overwinter in dead leaves.
Timing: Crops that can overwinter (such as leeks or carrots) should be planted in the fall. This gives
them time to become established before pests arrive in the spring.
Mechanical: Many eggs, larvae, cocoons, and adult insects can be removed by hand. Be sure that the
insect is properly identified prior to removing it so that beneficial insects are not destroyed in error.
Drowning insects in plain water or spraying them with soapy water are alternatives to squashing them.
Resistant Plants: Plants that are native to this area are often more resistant to pests and climate, etc.
Than are introduced plants. Many plant cultivars have been developed which are resistant to such
diseases as verticilium wilt and peach leaf curl. Grass seed mixes are also available for lawns that need
much less watering, mowing, and chemical use.
Growing Conditions: Plants, such as hostas, that require some shade are more susceptible to pests
when they are growing in the sun. Plants that are not properly fertilized or watered are less vigorous in
growth and tend to attract pests. Plants that prefer an acid soil, such as azaleas, will perform better and
be less susceptible to pests when they are frown in soil with the proper pH.
Chemicals: Chemicals are a small part of the IPM plan and should be applied only as needed after
reviewing all other alternatives.
Pesticide management
When use of a chemical is the best or only option, follow these simple guidelines:
1. Know what pest you are spraying for. Use the pesticide according to the manufacturer's
instructions and buy only the quantity needed. Many pesticides have a limited shelf life and may
be useless or degrade into even more toxic compounds if kept on the shelf.
2. Do not apply more than the specified amount. Overuse can be dangerous to your health as well
as the health of wildlife and the environment. If more than one chemical can be used to control
the pest, choose the least toxic. The word "caution" on the label means that the chemical is less
toxic than one that is labeled "warning ".
3. Do not spray on windy days, in the morning of what will be a very hot day, or when rain is likely to
occur. Herbicides can drift and injure valuable ornamental plants in either your or your neighbor's
back yard. Do not water heavily after application. Plants should be lightly watered BEFORE
application to prevent burning of the foliage, and to help evenly spread the chemical.
4. Never apply pesticides near streams, ponds, or wetlands (exception: approved applications for
aquatic weeds). Do not apply them to bare eroded ground (exception. use of low toxicity
herbicides such as Round -up to allow growth of desired planting in small areas). Many pesticides
bind to soil particles and can be easily carried into a stream or storm drain.
5. Pesticides should be stored well away from living areas. Ideally, the storage area should have a
cement floor and be insulated from temperature extremes. Always keep pesticides in their original
containers with labels in tact. Labels often corrode and become illegible in this climate and may
have to be taped onto the container.
6. Federal law now requires that all pesticides be labeled with the appropriate disposal method.
Leftovers should never be dumped anywhere, including a landfill. Take unwanted pesticides to
the County's hazardous waste collection days or Hazo House at the landfill.
28
7. Empty containers should be triple- rinsed and the rinse water used as spray. Once containers are
triple- rinsed, they are not considered hazardous waste and may be disposed of in most landfills.
However, call your local landfill before putting the container in the garbage.
8. If a pesticide is spilled onto pavement, it can be absorbed using kitty litter or sawdust. The
contaminated absorbent should be bagged and labeled and taken to Hazo House.
9. If the pesticide is spilled onto dirt, dig up the dirt, place it in a plastic bag and take it to Hazo
House.
10. Many pest control companies and licensed applicators have access to pesticides that are more
toxic than those available to the consumer. Check with the company before they spray indoors or
outdoors to find out what spray they will be using and what precautions, if any, are necessary
after the operator leaves.
Home remodeling
Remodeling uses some of the most toxic substances found in the home. Paints, preservatives, strippers,
brush cleaners, and solvents all contain a wide range of chemicals, some of which are suspected to be
carcinogens (cancer- causing). These products should never be dumped in a landfill or put down a sewer
or septic system.
1. When building a deck consider using wood instead of concrete. Wood decking allows rainwater to
drip onto the ground below, keeping it from becoming surface runoff.
2. Decks and sidewalks can also be built out of brick interlocking pavers or modular concrete. If
these surfaces are placed on a bed of well- drained soil gravel or sand, rainwater can infiltrate into
the around through them.
3. To reduce disposal problems, buy only the amount you need. Used turpentine or brush cleaner
can be filtered and reused. Paint cans should be allowed to dry and then be disposed of during a
hazardous waste collection day or at Hazo House.
4. Leftover paint can be given away, for example to a theater group. Contact the Thurston County
Health Department at 754 -4111 for other options.
5. Roof downspouts can be adjusted to infiltrate runoff where the soil is well drained. The runoff
from them can enter a gravel bed where it can infiltrate into the ground. For design criteria, see
your jurisdiction's drainage manual.
6. When gardening on slopes, reduce the potential for surface runoff by using terraces across the
face of the hill. These can be as simple as little soil "bumps" or can be elaborate using such
products as pressure- treated wood 4x4's or rock walls.
Septic system care and management
While septic systems do not seem to have a direct relationship with stormwater runoff, they can in some
instances be related.
1. Roof drains and stormwater runoff should be diverted away from drainfields. Excess water
reduces the capacity of the drainfield to absorb effluent from the septic tank.
2. Water from hot tubs should not be drained into a septic system all at once. They are not designed
to handle large volumes of chlorinated water. Either use the water on plants in the yard, or drain
the hot tub slowly over a period of days.
29
3. Septic tanks should be pumped regularly. Ponded water, damp places in the yard, foul odors
and /or a dark gray or black soil color may indicate septic drain field failure. Effluent from a
malfunctioning septic can cause disease and nitrate problems in groundwater. For septic system
assistance, contact the Thurston County Health Department at 786 -5490.
References
Puget Sound Water Quality Authority, Managing Nonpoint Pollution - an Action Plan for Puget Sound
Watersheds, 88 -31, June, 1989.
Washington State Dept. of Ecology, Water Quality Guide - Recommended Pollution Control practices for
Homeowners and Small Farm Operators 87 -30, revised June, 1991.
Washington State Dept. of Ecology, Hazardous Waste Pesticides, 89 -41, August, 1989.
30
GLOSSARY
BEST MANAGEMENT PRACTICE (BMP) - Structures, conservation practices, or regulations that
improve quality of runoff or reduce the impact of development on the quantity of runoff.
BIOFILTER (SWALE) - A wider and flatter vegetated version of a ditch over which runoff flows at uniform
depth and velocity. Biofilters perform best when vegetation has a thick mat of roots, leaves, and stems at
the soil interface (such as grass).
BIOFIL TRA TION - The process through which pollutant concentrations in runoff are reduced by filtering
runoff through vegetation.
BUFFER - The zone that protects aquatic resources by providing: protection of slope stability, attenuation
of runoff, and reduction of landslide hazards. An integral part of a stream or wetland ecosystem it
provides shading, input of organic debris, and coarse sediments to streams. It allows room for variation
in stream or wetland boundaries, habitat for wildlife, and protection from harmful intrusion.
CATCH BASIN - An inlet for stormwater set into the ground, usually rectangular and made of concrete,
and capped with a grate that allows stormwater to enter.
CHECK DAM - A dam (e.g., rock, earthen, log) used in channels to reduce water velocities, promote
sediment deposition, and /or enhance infiltration.
COMPOST STORMWA TER FILTER - A treatment facility that removes sediment and pollutants from
stormwater by percolating water through a layer of specially prepared bigleaf maple compost. Clean
water exits the bottom of the facility through a pipe, while stormwater flows in excess of the facility design
overflow the compost bed and bypass the facility.
CONSTRUCTED WETLAND - A wet pond with dead storage at varied depths and planted with wetland
plants to enhance its treatment capabilities.
CONTROL STRUCTURE OR FLOW RESTRICTOR - A manhole and /or pipe structure with a flow -
regulating or metering device such as a weir or plates with small holes known as orifices. This structure
controls the rate at which water leaves the pond.
CONVEYANCE - A mechanism or device for transporting water including pipes, channels (natural and
man - made), culverts, gutters, manholes, etc.
CRITICAL AREA - Areas such as wetlands, streams, steep slopes, etc. as defined by ordinance or
resolution by the jurisdiction. Also known as environmentally sensitive areas.
CULVERT - A conveyance device (e.g., concrete box, pipe) which conveys water from a ditch, swa /e, or
stream under (usually across) a roadway or embankment.
DEAD STORAGE - The volume of storage in a pond below the outlet which does not drain after a storm
event. This storage area provides treatment of the stormwater by allowing sediments to settle out.
DETENTION FACILITY - A facility (e.g., pond, vault, pipe) in which surface and storm water is temporarily
stored.
DETENTION POND - A detention facility in the form of an open pond.
DISPERSION TRENCH - An open -top trench filled with riprap or gravel that takes the discharge from a
pond, spreads it out, and spills (bubbles) the flow out along its entire length. Dispersion trenches are
used to simulate "sheet flow" of stormwater from an area, and are often used to protect sensitive adjacent
areas, such as wetlands.
31
DRAINAGE SYSTEM - The combination of Best Management Practices (BMPs), conveyances,
treatment, retention, detention, and outfall features or structures on a project.
DROP STRUCTURE - A structure for dropping water to a lower elevation and /or dissipating energy. A
drop may be vertical or inclined.
DRY POND - A detention facility that drains completely after a storm. This type of pond has a pipe outlet
at the bottom.
EASEMENT- A right afforded a person to make limited use of another's real property. Typical
easements are for pipes or access to ponds, and may be 15 to 20 feet wide.
EMERGENCY OVERFLOW OR SPILLWAY - An area on the top edge of the pond that is slightly lower in
elevation than areas around it. This area is normally lined with riprap. The emergency overflow is used
only if the primary and secondary outlets of the pond fail, in the event of extreme storms, or if the
infiltration capability of the pond becomes significantly diminished. If the emergency overflow ever comes
into play, it may indicate the pond needs to be upgraded.
ENERGY DISSIPATER - A rock pad at an outlet designed to slow the velocity, spread out the water
leaving the pipe or channel, and reduce the potential for erosion.
FREEBOARD - The vertical distance between the design high water mark and the elevation of the top of
the pond. Most ponds have one to two feet of freeboard to prevent them from overflowing.
INFILTRATION - The soaking of water through the soil surface into the ground (percolation is essentially
the same thing). Many ponds are designed to infiltrate or retain stormwater, and thus do not have a
regularly used discharge pipe.
INFILTRATION FACILITY (OR STRUCTURE) - A facility (pond or trench) which retains and percolates
stormwater into the ground, having no discharge (to any surface water) under normal operating
conditions.
JUNCTION - Point where two or more drainage pipes or channels converge (e.g., a manhole).
JURISDICTION - Olympia, Lacey, Tumwater, or Thurston County (as applicable).
LINED POND OR CONVEYANCE - A facility, the bottom and sides of which have been made impervious
(using, for example, a plastic liner or clay /silt soil layer) to the transmission of liquids.
LIVE STORAGE - The volume of storage in a pond above the outlet which drains after a storm event.
This storage area provides flood control and habitat protection for nearby streams.
MANHOLE - A larger version of a catch basin, often round, with a solid lid. Manholes allow access to
underground stormwater pipes for maintenance.
NATURAL CHANNEL - Stream, creek, river, lake, wetland, estuary, gully, swale, ravine, or any open
conduit where water will concentrate and flow intermittently or continuously.
OIL -WATER SEPARATOR -A structure or device used to remove oil and greasy solids from water. They
operate by using gravity separation of liquids that have different densities. Many catch basins have a
downturned plastic elbow that provides some oil -water separation.
OUTFALL - The point where water flows from a manmade conduit, channel, or drain into a water body or
other natural drainage feature.
RETENTION FACILITY - An infiltration facility.
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RETENTION POND - A retention facility that is an open pond.
REVETMENTS - Materials such as rock or keystones used to sustain an embankment, such as in a
retaining wall.
RIP RAP - Broken rock, cobbles, or boulders placed on earth surfaces, such as on top of a berm for the
emergency overflow, along steep slopes, or at the outlet of a pipe, for protection against the action of
water. Also used for entrances to construction sites.
RUNOFF - Stormwater
SAND FILTER - A treatment facility that removes sediment and pollutants from Stormwater by percolating
water through a layer of sand. Clean water exits the bottom of the facility through a pipe, while
stormwater flows in excess of the facility design overflow the sand bed and bypass the facility.
STORMWATER - That portion of precipitation that falls on property and that does not naturally percolate
into the ground or evaporate, but flows via overland flow, channels or pipes into a defined surface water
channel, or a constructed infiltration facility. Stormwater includes washdown water and other waste water
that enters the drainage system.
SWALE - A shallow drainage conveyance with relatively gentle side slopes, generally with flow depths
less than one foot. This term is used interchangeably with "BIOFILTER ".
TRASH RACK OR BAR SCREEN - A device (usually a screen or bars) that fits over a pipe opening to
prevent large debris such as rocks or branches from entering and partially blocking the pipe.
WET POND - A stormwater treatment pond designed with a dead storage area to maintain a continuous
or seasonal static water level below the pond outlet elevation.
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