City drainage plan moves forward

Yorkton Council received an update of the City's Storm Drainage Improvement Plan, and then proceeded to approve a series of expenditures for more work in 2013.

City Engineer Josh Mickleborough explained to-date the City has invested some $6 million drainage improvements. The work has included construction of the Brodie Pond, Dracup Pond #3 and channel, storm-shed modeling and a feasibility study for work in the Yellowhead area of the city.

The Dracup pond has a volume of 58,600 cubic metres, and the Brodie Pond 8,700 cubic metres helping manage about 250 acres within the city in terms of storm water, said Mickleborough, adding it has a secondary effect on another 220 acres. The cost of the two ponds was approximately $3.6 million.

That is only a portion of what could lie ahead.

Projected estimated expenditures for Victoria Stormshed is $16,900,000, said Mickleborough, adding further Dracup Stormshed improvements estimated at $4,500,000, potential Yellowhead storm pond estimated at $3,200,000, and Highway #9 crossing improvements estimated at $2,000,000.

Mickleborough said what is being considered includes;

Continuing work on Dracup channel, impacts on development of adjacent lands

Yellowhead Storm Pond

Logan Green Diversion

Improvements to Highway #9 crossing

Maple Crossing

Feasibility of Broadway Diversion?

Council went on to deal with a number of expenditures for the current year associated with drainage.

"For the last number of years Planning & Engineering, Public Works and Environmental Services have been working on building models for water, sanitary and storm water systems," said Mickleborough.

Currently the city has two separate models for the two major storm drainage areas in Yorkton: the Westside/Victoria Channel area and the Dracup Channel, he said.

"This leaves areas of the city and the drainage system out of the model. These computer models have many uses. They provide a detailed understanding of how your storm-water system operates; it allows for better prioritization during capital and maintenance planning, it allows for engineering analysis of improvements and development options; and facilitates the development of master plans. They are used extensively in the impact analysis of new development."

Mickleborough said bringing the models together will pay dividends.

"With respect to the ongoing drainage system improvements this will ensure that the continued capital investment will be optimized. In short, this expenditure will more than pay for itself as it will be used as a value engineering tool for all storm upgrades. This work will also inform the development of a storm water management master plan for the city," he said.

"Engineering Services requested a proposal to combine and expand the model from Associated Engineering. They have provided a cost of $64,000 to complete the work."

The budget for this work is proposed as part of the city wide storm improvements.

Councillor Chris Wyatt questioned if the project had gone to tender.

Mickleborough said it had not given Associated Engineering previous work on the modeling.

"I'd really like to see numbers (from tender)," countered Wyatt. "I'd sleep better knowing everybody had a chance to bid on it."

Wyatt would be the lone vote against accepting the recommendation from Administration to enter into a contract with Associated Engineering for the completion of a combined city wide storm water model and calibration in the amount of $64,000.00.

Council also approved a tender to construct a second retention pond on Dracup.

Mickleborough said the pond was part of the City's multi-year plan.

"One area identified for improvements as part of this plan is the Dracup drainage channel. The work in this area includes channel widening and improvements and the addition of ponds to increase storm water storage capacity," he said.

"The proposed pond will retain, temporarily storing the storm water for approximately 65 acres. This will increase downstream capacity as well as providing additional storage for upstream flows. The current project consists of the construction of a 2.8 acre pond with a 40m connection to the existing storm pipe network."

The original budget allocated to this project was $120,000 for design and $400,000 for construction for a total of $520,000.

"The consultant's construction estimate for this project was $790,000. Given this information it is recommended that this project proceed with the proposed budget, this is an increase of $202,298 over the conceptual estimate," said Mickleborough.

The tender approved was from Potzus Paving and Road Maintenance Ltd for $567,085.

The overall project has a budget of $722,298.

Work will also be undertaken along Harris Avenue in 2013.

"In 2012 City Council provided direction to review, design and report back with construction costing for improvements to the storm water network in the Harris subdivision. The main storm ditches along Harris Avenue need to be re-graded," reported Mickleborough.

"The proposed ditch improvement will allow storm water to move freely through the subdivision to its outfall in the Yellowhead subdivision. It will also address nuisance ponding issues in the ditches. The work consists of minor excavation work to re-grade the ditches, several culverts will be adjusted or replaced. The work will take place in the right-of-way unless there is an agreement with the adjacent property owner but will require open cuts of some driveways and roadways."

Two tenders were received, the lowest of $81,950 from On the Mark Excavating. The tender, accepted by Council is part of an over project budget of $102,645.

Cedarwood Crescent will also see drainage improvements this year.

"In review of city wide drainage issues Cedarwood Crescent was identified as having significant ponding during storm events. Last year funds were identified to address local and isolated drainage area improvements," said Mickleborough.

"This area drains via catch basins through a storm pipe that empties into the Highway #10 east ditch on the east side of the ditch. This ditch is flat and has a number of low areas that do not allow for proper drainage of the storm pipe resulting in ponding on Cedarwood Crescent.

"Directional boring a culvert in the same location, under Highway #10, will allow the storm water to cross the highway and to drain into an existing slough and north down the highway ditch."

Again two tender bids were received, the lowest of $47,500 from On the Mark Excavating.

The tender, unanimously accepted by Council is part of an overall project budget of $128,950.