Watertown building department

Watertown’s Community Development Division, part of Public Works, administers planning, zoning, building permits, inspections, and signs inside city limits. Its Building Services staff review and issue permits under the International Building and Residential Codes as adopted in Title 5 of the city’s Revised Ordinances. Watertown takes no paper applications: all building and engineering permits go through the city’s OpenGov portal. Codington County does not issue permits for property inside the city.

Adopted codes

In August 2026 the city adopted the 2024 International Residential Code (Ord 26-18) and the 2024 International Building Code (Ord 26-19), both with local amendments. Title 5 also adopts the 2024 International Mechanical Code and the 2024 International Fire Code. Some notable Watertown amendments to the IRC:

• Frost depth is 48 inches to the bottom of the footing, and the design ground snow load is 50 psf.
• Stair risers may be up to 8 inches.
• Frost-protected footings are not required for detached accessory buildings up to 1,300 sq ft. They are also not required for decks that are not supported by the dwelling or are 30 inches or less above grade.
• The IRC certificate-of-occupancy section and the swimming pool chapter (R326) are not adopted. Appeals go to the Board of Adjustment.
• For projects whose complete application was submitted within 180 days of the amendment’s effective date, the 2018 IRC climatic and geographic design criteria may be used.

What needs a permit

Title 21 (Section 21.0206) requires a permit to build, install, move, demolish, alter, or repair any building or structure. That includes fences, detached accessory structures, decks, and retaining walls over 4 feet. Placing a manufactured home requires a placement permit. The ordinance exempts:

Work	Permit?
Maintenance; painting, flooring, cabinets, countertops (unless part of a larger project)	No
Replacing gutters, downspouts, storm windows/doors, or similar siding	No (upgrades need a permit)
Repair, maintenance, or demolition of fences, decks, and accessory structures of 200 sq ft or less	No
Retaining walls 4 ft or less (no surcharge)	No
Seasonal pools or prefab pools under 24 in. deep; swings and play equipment	No
Any new or replacement fence	Yes, with exemptions in Chapter 21.61
Decks and all accessory structures	Yes

Under Chapter 21.61, a fence permit is not needed for a fence located entirely outside required setbacks, or for one under 3 feet tall and under 20 feet long. Residential fences may be up to 7 feet tall, but only 48 inches in a required front yard and 36 inches in the 25-foot clear-view triangle. A survey by a registered land surveyor is required if the fence will be within 12 inches of a property line.

Applying through OpenGov

Apply at watertownsd.viewpointcloud.com (the city’s watertownpermits.com address forwards there). Building, fence, sign, antenna, reroofing, pool, demolition, and moving permits are all filed online. Window wells, bathrooms, and patio covers are filed as residential alteration permits.

The city’s Resources page has fillable “standard plates” for an accessory garage, bathroom, covered patio, deck, roofing, window well, and wall section, plus code handouts on basement finishes, garage separation, egress, safety glazing, stairs and guards, and smoke/CO alarms.

The deck handout lists what to submit: an application, a survey or dimensioned site plan, and scaled construction drawings. It requires footing, framing, and final inspections. The accessory structure handout limits structures over 240 sq ft to a 24-foot peak height with a 9-foot side setback, and limits smaller structures to 12 feet with 4-foot side and rear setbacks. Lots with frontage on Lake Kampeska and Lake Pelican have their own shoreline setbacks.

2026 permit fees

Residential permit fees are based on valuation. The city values new construction per square foot: $90 for finished floor area, $50 for finished basement, $30 for unfinished basement, $40 for finished garage, $20 for unfinished garage, and $4,000 per fireplace. Remodels use the bid price. Selected 2026 fees:

Item	Fee
Valuation $1-$1,000	$25
Valuation $2,000-$50,000	$45 for first $2,000 + $5 per $1,000
Valuation $100,000-$1,000,000	$485 for first $100,000 + $3 per $1,000
Accessory structure, 240 sq ft or less	$25
Residential re-roof	$50
Residential plan review	$100
Commercial plan review	50% of permit fee
Investigation fee	$100
Work done without a permit	Equal to the permit fee
Certificate of occupancy violation	$100 per day

The Permit Fees page includes an online fee calculator.

Inspections, electrical, and plumbing

City handouts say to call (605) 882-6201 to schedule building inspections, with your address and permit number ready. Sidewalk, curb, and approach inspections go through Engineering at (605) 882-6202, at least 24 hours before pouring.

Watertown does not appear on the State Plumbing Commission’s list of cities that do their own plumbing inspections. The city’s accessory structure handout says separate electrical and plumbing permits are obtained from the SD Electrical Commission (605-773-3573) and the SD Plumbing Commission (605-773-3429).

Contractor licensing

Chapter 12.06 requires a city residential contractor’s license for paid work on one- and two-family dwellings and their accessory structures. Licenses expire December 31 each year. Applicants must show at least $500,000 per occurrence in general liability insurance, workers’ compensation coverage, and an excise tax number. You can apply or renew through OpenGov.

Owner-occupants acting as their own contractor are exempt, but may build no more than one single-family home every three years without a license. Electrical contractors need a separate city license under Chapter 9.02. See owner-builder permits for general background.

Engineering, floodplain, and zoning

• Engineering (605-882-6202) issues right-of-way, sidewalk, and approach permits. Sidewalk permits are $25 for up to four inspections. Right-of-way occupancy permits have a $50 base fee.
• Engineering also issues a combined grading/floodplain permit that expires each November 1. Sites over one acre need a Notice of Intent from SD DANR.
• Planning and zoning applications, PUDs, and historic preservation also go through Community Development. Appeals go to the Plan Commission/Board of Adjustment.

Office and contact

Community Development is in City Hall, 20 N. Maple Street, Watertown, SD 57201, open 8 a.m. to 5 p.m. Monday through Friday. Phone (605) 882-6201; the City Hall main line is (605) 882-6200.