"Of course, you will get paid for your labors, but now is not the time." The Mayor heads back into the house, leaving the butler, Nesmond, behind to answer any questions.
Directions were easy. You have already seen the Guildhall of Averndale sitting just outside of the old fort walls - a separate structure from the Bunkhouse that Jasper slept in last night. The building is magnificent - a stone foundations and select hand-carved lumber, a deliberate display of the combined artisans' talents. With a clerk's help, you will find the works manager in his office, who after a moment of confusion will rise and greet the party. He is happy to receive them and eager to get them to the job, prattling on about how happy he was to hear from the Mayor and how important it is that you inspect the downflow.
Leading the partying into the hillside, through a gated tunnel entrance, and down a stairwell, the party enters the underground Works. It is faint at first, but the sickly smell of sewage builds to an afoul stench, as they stop to unlock and then pass through several iron gates. You are led to the sluice gates where the flow is controlled. He turns to explain, with a smudge of some sort of salve under his nose to block the smell - holding a small container in his hand.
"I need you to find out what's been trying to crawl out from the downpipe." He points out some scratch marks on some of the ironbar door leading to the maintenance path next to the sewer channel. A little investigation might turn up that there of purposeful scratches in and around the locking mechanism. "We ignored it at first, cause they weren't getting through but the workers have been complaining about animal noises, so we put went to put out some poison, but when we sent someone to place bait and he was savaged along the arm before the beast was chased away! Nearly torn his arm off with bites! Then the pipe backed up and we can't send anyone down there until the beasties are put down. So... we really appreciate you fellars work." The man walks to the gate, pulls out an iron key, and then waits for your cue. "Just tell me when you're ready and I'll open the gate."