photo by: City of Lawrence

A flooded Watson Park is pictured in this undated City of Lawrence photo.

City leaders will soon receive a study of the Jayhawk Watershed that estimates improvements to the area’s flood-prone storm water system could cost up to $32 million.

As part of its meeting Tuesday, the Lawrence City Commission will receive an update on the findings and recommendations of a watershed study completed by JEO Consulting Group. The study includes an outline of recommended storm water projects and cost estimates to complete them.

The watershed includes parts of the Old West Lawrence and Oread neighborhoods, including areas that have had problems with flooding during heavy rainfall. Residents in the Old West Lawrence neighborhood have previously voiced concerns to the commission about flooding and have questioned why the city had not moved forward on some improvements included in a 1996 storm water management plan.

The study broke the watershed into four project areas and determined how much wider pipes and drainage tunnels in that area should be to adequately handle storm water. The estimated cost to replace the existing infrastructure is broken down for each project area, and the total estimated construction costs for all pipe and tunnel replacements is anticipated to be $23 million to $32 million.

JEO and city staff recommend that the city should proceed first with work in project area B, which starts at approximately the intersection of Eighth and Ohio streets and ends at approximately the intersection of Ninth and Mississippi streets. The memo states that construction in that area would eliminate a majority of the localized neighborhood flooding within the watershed and would relocate the storm sewer system within the city right-of-way.

The City of Lawrence agreed to purchase the house of a couple who sued the city after discovering a century-old storm water tunnel directly under their Old West Lawrence home at 812 Ohio St., as the Journal-World previously reported. Typically, city utilities are built along city streets, alleys or other right-of-way areas, but the 1911 arched brick drainage tunnel follows the course of a ravine that once ran from Mount Oread to the Kansas River and runs through multiple private properties.

The main trunk line of the existing storm sewer system in the Jayhawk Watershed begins at approximately the intersection of Fambrough Drive and Illinois streets and terminates at the Kansas River, according to a city staff memo to the commission. As part of the study, JEO developed a hydrological and hydraulic model of the storm water system to identify improvements necessary to mitigate localized flooding and provide preliminary design of those improvements.

The city has budgeted $16 million total in its capital improvement plan toward projects in the Jayhawk Watershed over the next several years. The proposed allocation for the project B area, which is included in the 2023-27 CIP, is $10 million. The memo states that the cost of an engineering design contract will be brought to the City Commission in the near future.

The Lawrence City Commission will convene at 5:45 p.m. Tuesday at City Hall, 6 E. Sixth St.