Dock and bulkhead permits on Lake Washington and Lake Sammamish

Short answer: there is no single Lake Washington dock permit. A dock or bulkhead on Lake Washington or Lake Sammamish passes through your city’s shoreline program, a Hydraulic Project Approval from the Department of Fish and Wildlife, the Army Corps of Engineers and, where the lakebed is state land, the Department of Natural Resources. The state shoreline permit turns on cost. A freshwater dock that replaces an old one at equal or smaller size, in a city with an updated shoreline program, is exempt up to $28,000. Any other freshwater dock is exempt up to $13,900. A normal protective bulkhead has no dollar line but strict conditions.

I am David Meade, an architect in Kirkland. I design houses and administer construction for the owner, and I do not build. A marine engineer or marine contractor designs and builds docks and bulkheads; I am not offering that work here. The first feasibility check is free and takes about a day. Rules are as of 30 October 2026; confirm with your city.

The permit stack: who decides what

A project touches every row that fits its work. No row replaces another.

Layer	Who decides	What it decides
State shoreline permit or exemption	Your city issues it; the state sets the rules	Whether the work needs a substantial development permit or fits an exemption (RCW 90.58.030(3)(e), WAC 173-27-040).
City shoreline program	Your city	Size, location, materials, planting and what counts as repair. Six programs are compared below.
City building permit	Your city	The structure. Mercer Island asks for framing plans, pile calculations and, for boats over 25 feet, an engineer.
Hydraulic Project Approval	Fish and Wildlife	Protection of fish life, the only ground for denying or conditioning it (RCW 77.55.021(7)).
Section 10 permit	Army Corps of Engineers	Structures in or affecting navigable waters (33 CFR 322.3(a)). The Corps tells you whether it applies to your site.
Aquatic lands authorization	Department of Natural Resources	Use of state-owned lakebed. A residential owner next to it may install a private recreational dock without charge, under conditions (RCW 79.105.430(1)).

Cities ask for proof of the others. Kirkland wants documentation at building permit submittal that the Corps and Fish and Wildlife approved an alternative dock design (KZC 83.270(4)(b)), Mercer Island asks the same (MICC 19.13.050(F)(3)), and Issaquah may require state and federal approvals first (Shoreline Program 6.1.5). Sammamish’s dock checklist (2023-11) treats even a repair as a building permit for a Structure in Water.

The dock dollar lines and the conditions behind them

The state exempts a dock from the substantial development permit when it is for pleasure craft only and for the private noncommercial use of the owner, lessee or contract purchaser of single or multiple family residences. A community dock counts (RCW 90.58.030(3)(e)(vii); WAC 173-27-040(2)(h)). In fresh water two dollar lines apply, effective 5 August 2023 (WSR 23-13-012):

Freshwater dock	Exempt up to	Conditions
Replaces an existing dock	$28,000	Equal or lesser square footage than the dock it replaces, and located in a county, city or town that has updated its master program under the 2003 state guidelines (chapter 173-26 WAC).
Any other freshwater dock	$13,900	New docks, larger replacements, and replacements where the program has not been updated.

Fair market value is the open market bid price for the whole job, what a contractor would charge start to finish, plus donated labor, equipment or materials (WAC 173-27-030(8)). Work within five years is added together: if the combined value of earlier and later construction passes the limit, the later work is a substantial development. The RCW and the WAC still print the base $20,000 and $10,000 and leave the indexing to the Office of Financial Management, so read the notice for today’s figures. The statute orders an adjustment every five years beginning 1 July 2018, so the next is expected around 2028 (my inference); watch the State Register.

An exemption covers only the permit; the program still applies (WAC 173-27-040(1)(b)). When exempt work also needs a Corps Section 10 or 404 permit, the city writes a letter of exemption to you and to Ecology (WAC 173-27-050). My shoreline exemption guide covers that letter.

A worked example with the state thresholds

Your city has an updated program, and you replace a 480 square foot dock with a 450 square foot one. The bid plus materials you supply comes to $26,500. These are example numbers, not quotes.

• Same size or smaller. The limit is $28,000. $28,000 minus $26,500 leaves $1,500 of room, so the dock is exempt from the state permit. The city program and the Hydraulic Project Approval still apply.
• More dock work three years later. You add $4,000 of dock construction. $26,500 plus $4,000 is $30,500, which is $2,500 over the $28,000 line ($30,500 minus $28,000). The later work is a substantial development. The WAC excludes appurtenances from the meaning of a dock, so ask your city whether an item such as a boat lift counts.
• No dock today. You build a new 400 square foot dock for the same $26,500. The limit is $13,900. $26,500 minus $13,900 is $12,600 over, so a substantial development permit is needed.

Where the figures come from: the Office of Financial Management applied the 24.5 percent rise in the Seattle area price index from April 2018 to April 2023 to the prior limits. $22,500 times 1.245 is $28,012.50, rounded to $28,000. $11,200 times 1.245 is $13,944, rounded to $13,900.

Dock replacement permit: where repair ends and replacement begins

A repair keeps the old dock’s rules. A replacement meets the new-dock rules, and every program draws the line in a different place.

Program	Repair side	Replacement side
Mercer Island	Repair or complete replacement of a legal structure is allowed if area, width, length and height do not grow. Over 50 percent of framing elements in five years requires fully grated decking, a 1.5 to 5 foot height and the width limits; over 50 percent of decking surface requires grating (MICC 19.13.050(F)(2)).	A larger dock meets the new-dock standards (F)(1). Moving one needs a net gain in ecological function (F)(2)(iv).
Kirkland	Decking or substructure plus fewer than 50 percent of the piles, with five years since the last repair proposal, is a minor repair (KZC 83.270(8)).	The whole dock, or over 50 percent of the piles and of the decking or substructure, meets the new-dock standards unless the city approves an alternative design. Skirting comes out (83.270(6)).
Bellevue	Repair or replace in the existing configuration and footprint, with grated decking (LUC 20.25E.065.H.5).	Replacing 75 percent or more of the near shore piles within five years brings in the standards for reconfigured docks.
Sammamish	Replacing 25 to 75 percent of piles on Lake Sammamish needs 18 foot spacing where engineering allows and grating on replaced decking (SMC 25.07.050(1)(k), in the 2011 text and the city’s 2019 draft).	75 percent or more of the piles, counted over the dock’s lifetime, means a replacement dock.
Issaquah	Replacing less than 50 percent of decking, substructure and piles is a minor repair. Grating is required where more than half the decking is replaced, and on all solid decking within 30 feet of the water (Shoreline Program 6.1.5).	The whole dock, or over 50 percent of the piles together with over 50 percent of the decking and its support, meets the new-dock standards (70 feet or 8 feet of depth, 480 square feet) unless the city approves an alternative no larger than the old dock. It also triggers planting and dock lighting standards.
Medina	Repair and like-for-like replacement of the same size, shape and configuration is allowed (MMC 16.65.060, per the city’s SMP User Guide, July 2023).	Additions meet MMC 16.65.030. Docks built before 18 April 2014 are judged by different standards.

Fish and Wildlife adds two tests (WAC 220-660-140(3)). A structure counts as a replacement only if it was usable at the site in the 12 months before you apply, meaning no major deterioration or section loss in critical structural components. And replacing more than 33 percent or 250 square feet of decking, or the substructure, requires functional grating in the replaced part. On a failing dock, the date matters.

New-dock dimensions are in my Lake Washington and Lake Sammamish waterfront pages. The programs I read share one dock per lot, 480 square feet for one owner and grated decking.

Bulkhead permit in Washington: the exemption and the city test

The state exempts “the normal protective bulkhead common to single-family residences.” WAC 173-27-040(2)(c) limits it to structures installed at or near, and parallel to, the ordinary high water mark for the sole purpose of protecting an existing single-family residence and appurtenant structures from loss or damage by erosion. It is not exempt if built to create dry land. A vertical wall may use no more than one cubic yard of fill per foot of wall as backfill. If the water has cut in behind a failing bulkhead, the replacement goes at or near the new line. Then the city asks whether you need the wall at all:

Program	What it asks before a bulkhead goes in
Mercer Island	Replacement needs a demonstrated need and may not go waterward of the high water mark or the old wall, with a narrow exception for a house occupied before 1 January 1992. A new or enlarged structure needs a geotechnical analysis showing danger from waves or currents (MICC 19.13.050(B)).
Kirkland	No geotechnical report is needed when the house is within 10 feet of the high water mark. Farther away, a report must show a significant possibility of damage within three years, and soft measures come first (KZC 83.300).
Bellevue	Under 75 percent of the structure in five years is repair. Within 10 feet of the high water mark the wall is presumed necessary; otherwise a professional’s report must show need (LUC 20.25E.080.F.5 and F.6).
Sammamish	Hard stabilization only when alternatives fail and the house is likely to be damaged within three years, designed by a licensed geotechnical engineer or geologist (SMC 25.07.070, 2011 text).
Issaquah	No new hard structure without conclusive evidence of danger within three years, plus peer review (Shoreline Program 6.1.4).
Medina	Soft measures first. Hard measures when the house is within 10 feet of the water line, or farther with a geotechnical analysis, plus planting (MMC chapter 16.65, per the SMP User Guide).

Fish and Wildlife ranks the choices: no action, then biotechnical, then a mix, then structural, always the least impacting feasible option (WAC 220-660-130(3)(b)). For lakes it says to remove rock and concrete bulkheads whenever feasible and use soft shore methods (5)(b). If storm damage moved the water line landward, repair in the existing footprint must happen within three years (5)(a).

When the house and the water share a lot

The house, dock and bulkhead each have their own exemption: (2)(g), (2)(h) and (2)(c) of WAC 173-27-040. Under (1)(d), if any part is not eligible, a substantial development permit is required for the entire development. Keep the three decisions apart until each exemption is clear. My lakefront lot feasibility guide covers what to check before you buy.

The less obvious overlap is planting. A new dock in Kirkland brings native plantings in at least 75 percent of the nearshore strip, 10 feet deep on average, with five years of monitoring (KZC 83.270(5)). Mercer Island’s standard path for a new moorage includes a vegetation plan inside the 25 foot shoreline setback (MICC 19.13.050(F)(1)). Issaquah requires planting across at least 80 percent of the lot width for a new dock, a replacement or a major repair (6.1.5). The house shares that strip, so plan it once.

What I could not read

• Seattle. The rules are in SMC chapter 23.60A, and the code site did not open for me. Ask SDCI.
• Redmond and Renton. Redmond points to RZC 21.68.070.E for docks; I did not open it. I did not look for Renton’s program.
• Versions. Mercer Island is the Ecology copy of chapter 19.13 effective 9 July 2020; Ordinance 23C-15 (effective 22 July 2024) later added a marina use, and I did not open that text. Kirkland is current through Ordinance 4781 (1 February 2022). Bellevue is the Ecology copy dated August 2018. Sammamish is the Ecology copy effective 31 August 2011 plus the city’s 29 May 2019 draft; the city adopted that update by Ordinance O2019-493 (19 November 2019), and Ecology lists a further amendment open for comment in late 2025, but the current code sat behind a bot check. Issaquah is Ordinance 3021 (passed 1 May 2023), effective on Ecology’s final approval of 12 May 2025. Confirm the current section.

What to send me for the free feasibility check

Send the address, whether you own the lot or are buying it, and what you are weighing. Photos of the dock and bulkhead help. The first basic feasibility check is free and usually takes about a day. An in-depth analysis is $1,500 and takes 2 to 3 weeks.

If you then hire me, I quote a fixed fee for design and permit, about $10,000 to $200,000, set by project budget and location. My smallest project budget is $750,000, and design to permit submission typically takes 2 to 4 months. Construction is priced separately by a builder, because I administer construction and do not build.

I have worked as an architect since 1996. I have been an AIA member since 1992 and an NCARB member since 1996.

Sources read on 30 October 2026: RCW 90.58.030, WAC 173-27-040, WSR 23-13-012, RCW 77.55.021, WAC 220-660-140, RCW 79.105.430, and each city’s program as posted by the city or Ecology.

Questions

Do I need a permit to replace a dock on Lake Washington?

Yes, at least one and usually several. A replacement dock may be exempt from the state shoreline substantial development permit, up to $28,000 when it is equal or smaller in size and your city has an updated program, but your city’s shoreline program still applies. Fish and Wildlife must give a Hydraulic Project Approval before work starts, the Corps decides whether Section 10 applies, and DNR is involved where the bed is state land.

Is there a King County dock permit?

Only for land the county itself governs. King County’s shoreline page says a substantial development permit is required within 200 feet of a lake for work over $8,504 and lists a processing time of 120 days. If your lot is inside a city such as Mercer Island, Kirkland, Bellevue, Medina, Sammamish, Issaquah or Redmond, the city runs the local shoreline program, so start there. For bulkheads, the county’s handout (web dated 10 November 2012) requires a geotechnical report and sets a four foot height limit on lakes; confirm it is current.

How much can a dock cost before it needs a shoreline permit?

For freshwater docks, $28,000 if the dock replaces an existing dock at equal or lesser square footage in a county, city or town that has updated its master program under the 2003 guidelines, and $13,900 for any other dock. Both took effect 5 August 2023 (WSR 23-13-012). Fair market value includes donated labor and materials, and later work within five years is added to the earlier work. The city program and the other agencies still apply.

Do I need a bulkhead permit in Washington?

A normal protective bulkhead that protects an existing single-family house, sits at or near and parallel to the ordinary high water mark and is not built to create dry land is exempt from the state substantial development permit (WAC 173-27-040(2)(c)). You still need your city’s exemption or approval, a Hydraulic Project Approval, and often a Corps permit. Cities such as Mercer Island, Sammamish and Issaquah ask for geotechnical evidence of need, Kirkland asks for it when the house is more than 10 feet from the high water mark, and Fish and Wildlife prefers soft shore methods.

How long does a Hydraulic Project Approval take?

Fish and Wildlife has 45 calendar days from a complete application to grant or deny approval. The period is suspended in listed cases, for example if the site is physically inaccessible or the applicant asks for a delay (RCW 77.55.021). The approval can be denied or conditioned only to protect fish life, and it is valid for up to five years from issue.

Does the Army Corps have to approve a private dock?

Section 10 of the Rivers and Harbors Act requires a permit for structures or work in or affecting navigable waters of the United States, unless an exemption or a nationwide or regional general permit covers it (33 CFR 322.3(a)). Washington’s rule says to ask the Corps. I found no published Corps processing time to quote.

Does the state charge me for a dock over state-owned lake bed?

The statute lets the abutting residential owner install and maintain a dock on state-owned shorelands, tidelands or beds of navigable waters without charge if it is used only for private recreation and the area is not subject to prior rights. The dock cannot be sold or leased apart from the house or used to moor boats commercially or residentially, and other rules still apply (RCW 79.105.430(1)). Ask DNR whether the bed in front of your lot is state-owned; it can revoke the permission on a finding of public necessity.

Can I repair a dock without a permit?

Not safely. Repair can be exempt from the state permit as normal maintenance and repair (WAC 173-27-040(2)(b)), but cities add their own steps. Mercer Island wants a framing plan if up to 50 percent of the piles or framing is replaced. Sammamish asks for a shoreline exemption letter for dock repair. Kirkland, Bellevue and Issaquah set percentages beyond which a repair becomes a replacement. Fish and Wildlife may still require an approval for work that changes the bed.

Does Piper Cole design the dock or build it?

Piper Cole Architects does not build. It designs houses and administers construction for the owner. A marine engineer or marine contractor typically designs and builds a dock or bulkhead, and I am not offering dock or bulkhead design on this page. The first basic feasibility check is free and takes about a day.

Authoritative sources

Regulatory requirements referenced in this guide are set by the official agencies below. Rules change, always confirm current requirements with the source:

• Seattle Dept. of Construction & Inspections (SDCI)