(1) Any item, or items of the same kind of materials, equipment, or supplies purchased, the estimated cost of which is in excess of ((fifteen))thirty thousand dollars, exclusive of sales tax, shall be by contract. However, a district may make purchases of the same kind of items of materials, equipment, and supplies not exceeding ((seven))twelve thousand ((five hundred)) dollars in any calendar month without a contract, purchasing any excess thereof over ((seven))twelve thousand ((five hundred)) dollars by contract.

(2) Any work ordered by a district commission, the estimated cost of which is in excess of ((twenty-five))fifty thousand dollars, exclusive of sales tax, shall be by contract. However, a district commission may have its own regularly employed personnel perform work which is an accepted industry practice under prudent utility management without a contract. For purposes of this section, "prudent utility management" means performing work with regularly employed personnel utilizing material of a worth not exceeding ((one))three hundred ((fifty)) thousand dollars in value without a contract. This limit on the value of material being utilized in work being performed by regularly employed personnel shall not include the value of individual items of equipment ((purchased or acquired and used as one unit of a project)). For the purposes of this section, the term "equipment" includes but is not limited to conductor, cabling, wire, pipe, or lines used for electrical, water, fiber optic, or telecommunications.

(3) Before awarding a contract required under subsection (1) or (2) of this section, the commission shall publish a notice once or more in a newspaper of general circulation in the district at least thirteen days before the last date upon which bids will be received, inviting sealed proposals for the work or materials. Plans and specifications for the work or materials shall at the time of publication be on file at the office of the district and subject to public inspection. Any published notice ordering work to be performed for the district shall be mailed at the time of publication to any established trade association which files a written request with the district to receive such notices. The commission may, at the same time and as part of the same notice, invite tenders for the work or materials upon plans and specifications to be submitted by the bidders.

(5) Whenever equipment or materials required by a district are held by a governmental agency and are available for sale but such agency is unwilling to submit a proposal, the commission may ascertain the price of such items and file a statement of such price supported by the sworn affidavit of one member of the commission, and may consider such price as a bid without a deposit or bond.

(6) Pursuant to RCW 39.04.280, the commission may waive the competitive bidding requirements of this section and RCW 54.04.080 if an exemption contained within RCW 39.04.280 applies to the purchase or public work.

(7)(a) A district may procure public works with a unit priced contract under this section, RCW 54.04.080, or 54.04.085 for the purpose of completing anticipated types of work based on hourly rates or unit pricing for one or more categories of work or trades.

(b) For the purposes of this section, unit priced contract means a competitively bid contract in which public works are anticipated on a recurring basis to meet the business or operational needs of a district, under which the contractor agrees to a fixed period indefinite quantity delivery of work, at a defined unit price, for each category of work.

(c) Unit priced contracts must be executed for an initial contract term not to exceed three years, with the district having the option of extending or renewing the unit priced contract for one additional year.

(d) Invitations for unit price bids shall include, for purposes of the bid evaluation, estimated quantities of the anticipated types of work or trades, and specify how the district will issue or release work assignments, work orders, or task authorizations pursuant to a unit priced contract for projects, tasks, or other work based on the hourly rates or unit prices bid by the contractor. Where electrical facility construction or improvement work is anticipated, contractors on a unit priced contract shall comply with the requirements under RCW 54.04.085 (1) through (5). Contracts must be awarded to the lowest responsible bidder as per RCW 39.04.010.

(e) Unit price contractors shall pay prevailing wages for all work that would otherwise be subject to the requirements of chapter 39.12 RCW. ((Prevailing wages for all work performed pursuant to each work order must be the rates in effect at the time the individual work order is issued))Prevailing wages for all work performed pursuant to each work order must be the prevailing wage rates in effect at the beginning date for each contract year. Unit priced contracts must have prevailing wage rates updated annually. Intents and affidavits for prevailing wages paid must be submitted annually for all work completed within the previous twelve-month period of the unit priced contract.

For the awarding of a contract to purchase any item, or items of the same kind of materials, equipment, or supplies in an amount exceeding ((fifteen))thirty thousand dollars per calendar month, but less than ((sixty))one hundred twenty thousand dollars per calendar month, exclusive of sales tax, the commission may, in lieu of the procedure described in RCW 54.04.070 and 54.04.080 requiring public notice to invite sealed proposals for such materials, equipment, or supplies, pursuant to commission resolution use the process provided in RCW 39.04.190. Waiver of the deposit or bid bond required under RCW 54.04.080 may be authorized by the commission in securing such bid quotations.