Pond Maintenance Contracts: Garden Ponds vs. Stormwater Retention Ponds

“Pond maintenance” covers very different jobs. Cleaning a backyard water garden, managing the stormwater pond behind a subdivision and caring for a farm pond call for different skills, different contracts and, sometimes, different licenses. Before comparing quotes, it helps to know which kind of pond you have and what a maintenance agreement for it should actually contain.

Which kind of pond is it?

• Backyard water gardens and koi ponds are lined, usually small, and kept for looks and fish. Maintenance is about water quality, pumps, filters and periodic cleanouts.
• Stormwater wet ponds (often called retention ponds) are engineered to treat runoff from roofs, roads and parking lots. In North Carolina they are stormwater control measures (SCMs) and many come with regulatory maintenance duties.
• Farm and recreational ponds are larger, usually earthen impoundments where fish management and aquatic weeds are the main issues.

Pond-service businesses often specialize. Triangle Pond Management, for example, lists its lake, pond and stormwater services separately from its water-garden cleanouts.

Stormwater (retention) ponds: maintenance is an obligation

If your HOA, business or property owns a stormwater wet pond, maintenance is usually more than a nice-to-have. NC DEQ’s Stormwater Design Manual chapter on SCM operation and maintenance says regular inspection and maintenance is an ongoing regulatory responsibility for most required SCMs, typically including inspections throughout the year, inspection records and often annual inspections and reporting. Maintenance is usually the owner’s responsibility, which in most cases is a private individual, a corporation or a homeowners association.

The manual recommends an Inspection and Maintenance Agreement as part of the design plans. It typically states how often inspections are needed, which components must be inspected, what problems may be found and the remedy for each. Authorities may require these agreements to be signed and notarized; when they are, DEQ says they should be recorded with the Register of Deeds, and the documents should be handed on when maintenance responsibility changes hands. If you are on an HOA board, start by finding that agreement and the pond’s plans: they define what your contractor has to do.

What DEQ’s sample provisions call for

The wet pond chapter (C-3) of the design manual includes sample operation and maintenance provisions. Among them:

• Inspect the pond quarterly and within 24 hours after every storm of more than 1.0 inch (1.5 inches in coastal counties), keep records in a known location, and repair problems immediately.
• Have a dam safety expert inspect the embankment once a year.
• Clean out the forebay, the settling area at each inlet, if sediment reduces its depth to less than 75 percent of its design depth. Remove sediment from the forebay or main pool once it exceeds the design storage depth, and dispose of it where it will not affect streams or the pond.
• Remove shrubs that start growing on the embankment, and consult a dam safety specialist before removing a tree there. Bring in a professional if there are signs of muskrats or beavers.
• Consult a professional if algae covers more than half the treatment area. If cattails, phragmites or other invasive plants cover half the surface, wipe them with herbicide rather than spraying.
• Do not fertilize after the initial establishment, and keep stable groundcover in the drainage area to reduce the sediment that washes in.

The A-7 chapter suggests each inspection record include the date, the condition of each element, any work performed and who did it, and issues to watch.

Who does what

According to DEQ, simple items such as mowing, litter removal and minor landscaping can be done by the owner or folded into a regular grounds maintenance contract. The manual recommends professionals for more specialized work: engineers for structures, outlets, embankments and dams; grading and sediment removal by professional contractors; and appropriate specialists for inspections of vegetation and structures. NC State University runs an SCM inspection and maintenance certification program, and DEQ notes there are many companies in North Carolina that specialize in SCM inspection and maintenance. DEQ’s SCM operation and maintenance page also recommends inspecting SCMs at least quarterly and after larger storms of more than 1 inch in 24 hours.

On budgeting, DEQ says the biggest factor in maintenance cost is the condition of the drainage area upstream: a heavy sediment load makes upkeep dramatically more expensive. It suggests a dedicated fund, such as an escrow account for sediment removal and major repairs; in a subdivision, that could combine an initial developer payment with regular HOA contributions.

Weeds, algae and fish: two rules to know

Herbicide in water needs the right license. Anyone applying pesticides to someone else’s property for compensation must be licensed by the NC Department of Agriculture and Consumer Services, and NC State Extension’s licensing guide lists Aquatic Pest Control, covering ponds, lakes and streams, as its own category. Ask any contractor treating pond weeds or algae for the license and its categories.

Grass carp are regulated. The NC Wildlife Resources Commission allows only triploid grass carp certified as sterile. A private pond owner can use the receipt from a licensed triploid grass carp distributor as the stocking permit if the pond is a private pond as the rules define it (wholly on one owner’s or one group of joint owners’ land, with no escape or entry for fish from public waters), is under 10 acres, and is stocked with no more than 150 fish. Larger stockings need a permit application, and NCWRC suggests asking your district fisheries biologist if you are unsure whether your pond qualifies.

Backyard water gardens: what a service plan includes

For a lined garden pond, the big job is usually the cleanout. Triangle Pond Management describes draining the pond, removing the “muck,” power washing, scrubbing and refilling, with fish held in oxygenated tanks and acclimated back afterward. Pondscapes of Charlotte lists one-time cleanouts from $1,275, including a complete drain, pressure wash, debris removal, plant trimming and equipment inspection, and leak detection starting at $500. Hoaglandscape’s annual maintenance packages, each including a spring drain and clean, run from $1,980 a year for a pond up to 90 square feet to $7,000 a year for bi-monthly service on a pond up to 330 square feet. Those are the providers’ own published figures, not quotes or market averages.

A contract checklist for any pond

• Visit schedule. How many visits a year, in which months, and whether storm-triggered inspections are included.
• Scope per visit. Exactly which tasks happen each visit, and what is billed separately, such as sediment removal, repairs or plant replacement.
• Licenses. The pesticide license and category if any treatment is applied to the water or banks.
• Fish. How fish are handled during a drain or cleanout, and who is responsible if fish are lost.
• Records. For a stormwater pond, written inspection reports that match the recorded maintenance agreement.
• Problems found. A separate approval step before repairs or extra work are added.

Find pond help

Our North Carolina pond cleaning directory covers garden ponds and water features, by city, including Wilmington, Charlotte and Raleigh. Our pond cleaning quote guide explains how to compare written estimates. For a stormwater pond, look for SCM inspection and maintenance specialists and an engineer as DEQ describes, rather than a water-garden service alone.