Inter Office Memo

To: Mike Wildgen – City Manager

From: Chuck Adcock – Wastewater Master Plan Project Coordinator

Re: Southeast area development

Date: March 9, 2004

Last fall, the Peridian Group (representing a development group), requested the Douglas County Commissioners to consider the development of  several sanitary sewer benefit districts which would ultimately serve the southeast area of Lawrence (east of O’Connell & south of 23^rd.) The County Commissioners asked the City to investigate the feasibility of this proposal, particularly as it relates to capacity issues for the existing/planned sanitary sewer and wastewater treatment systems.  Although Keith Browning has provided them with updates, the County Commission is still anticipating a complete report from City staff subsequent to our review of this development proposal. 

Over the past months, the Utility, Public Works & Planning departments have worked with Black & Veatch & the Peridian Group to address specific wastewater issues relating to this area.   The main concern identified during this review was the discrepancy between the population density allocated for this area in the 2003 Master Plan and the greater density proposed by Peridian.

Black & Veatch has recently provided a technical memorandum (see attached) to address population density projections as they relate to capacity issues for existing and planned sanitary sewer pump stations and the Wastewater Treatment Plant (WWTP). The memorandum provides an analysis of the proposed development and offers two options for consideration that are based on this technical engineering analysis:

Option A would involve the conveying of all southeast area flow to the Kansas River WWTP and would require an increase in treatment capacity at that location. Due to WWTP site restrictions, this option would be difficult and is not recommended by Black & Veatch.

Option B would involve conveying all short term flows from the southeast area to the Kansas River WWTP. After the Wakarusa WWTP is constructed (projected in the Master Plan to be on-line in 2011), these flows would be redirected to this new plant. This is the Black & Veatch recommended option.

Both options would require significant improvements to the existing East Hill Business Park Pump Station (PS#25), so that capacity for the complete development of the Business Park can be maintained. These improvements to PS #25 are not called for in the CIP schedule until 2008, per the recently adopted Wastewater Master Plan.

As mentioned above, the proposed development plan for the area contained within this southeast sub-basin includes population projections that are significantly higher than the population projections developed by the Planning Department that were based on Horizon 2020 and Transportation 2025’s future land use map.  The Planning Department projections were what were forwarded to Black & Veatch for development of the Wastewater Master Plan.  The sale of the Farmland property (both north and south of K-10 Highway) has also increased the land areas affected by the those original population projections developed by the Planning Department..  Staff would urge the consideration of additional options from a land use perspective, given the adequate public facilities policy implications that are inherent is this decision-making process.

The following considerations are presented for additional discussion:

§ Restricting the development in this area to that which more closely matches the population and density projections used in development of the Wastewater Master Plan will mean that all the sanitary sewer flow can be accommodated at the existing Kansas River WWTP.

§ Consideration of the costs to expand the size of the planned EL2 Pump station and the existing Pump Station #25.  A policy decision regarding the developer’s appropriate share of these costs will be an important factor, staff assumes, in the decision to approve a development that includes the higher than anticipated population density.

§ Timing and staging of the various improvements to the sanitary sewer system (includes lift stations, gravity system, and WWTP construction) are scheduled in the Master Plan according to population projections of a different density and following a different schedule than projections presented by the proposed development.  Since increasing the density and moving the schedule for improvements forward could require a revision to the scheduling of other system improvements elsewhere, those revisions would need to be studied not only in terms of who pays and what is the capacity of the improvements, but also how the improvements would be timed to reduce any negative impacts to downstream systems and/or to the existing WWTP capacity.

§ The Commissions [City and County] have not approved a specific development or area plan for the Southeast Area.  It would greatly assist developers and future commissions if this step were taken next. A development plan can consider the phasing in of appropriate land uses based on the availability of public infrastructure to support the quantity and density of land use proposed. This would, for example, permit the limiting of industrial uses to those which are not heavy water and wastewater users.

§  Annexation of an area is another important tool in controlling the development of an area to urban intensities.  In this situation, as in most, it is more consistent with Horizon 2020 to annex the entire section and one-half in the southeast area and plan for the ultimate (and desirable) future land uses while regulating the development phasing through platting .

Summary

Staff considers the technical review of this issue, per the Black & Veatch memorandum, to be only a part of the factors that need to be considered regarding the proposed development and the associated sanitary sewer benefit districts.  Given the voiced concern of the City Commission that adequate public facilities are in place prior to development on a scale such as that which is proposed, we would suggest that this matter be brought before the City Commission for their review and direction prior to providing a response to the County regarding the appropriateness of the benefit districts.